REPORT TO THE 2024
LEGISLATUREANNUAL REPORT FROM THE
HAWAI‘I NATURAL ENERGYINSTITUTE
HRS 304A-1891
December 2023

Hawai‘i NaturalEnergy
Energy InstituteDecember 2023
Hawaiʻi Natural
Institute

Annual Report

School of Ocean and Earth Science and Technology
University of Hawaiʻi at Mānoa
Annual Report to the 2024 Legislature
HRS 304A-1891

Annual Report on Activities, Expenditures, Contracts Developed, Advances in Technologies,
Work in Coordination with State Agencies and Programs, and Recommendations for Proposed
Legislation, required in accordance with HRS 304A-1891 (Act 253, SLH 2007).

1. INTRODUCTION
The Hawai‘i Natural Energy Institute (HNEI) was created in 1974 to facilitate the development of
the state’s natural energy resources and reduce fossil fuel use in Hawaiʻi. Early efforts included
resource assessments, demonstration projects, and research and development in the areas ofalternative fuels, bioenergy, solar, and geothermal systems. In the early 2000s, HNEI took a
growing leadership position in the development of public-private partnerships to accelerate theacceptance and integration of renewable energy technologies into Hawai‘i’s energy mix. HNEI
emerged as a leader for sustainable energy development and the deployment and demonstration of
emerging energy technologies.
In 2007, the Hawai‘i Legislature (Act 253) established HNEI in state law with an expanded
mandate to coordinate with state and federal agencies to demonstrate and deploy renewableenergy, energy efficiency, and peak demand reduction technologies. Act 253 (2007) alsoestablished the Energy Systems Development Special Fund (ESDSF) and directed that it bemanaged by HNEI. Three years later, in 2010, Act 73 authorized 10 cents of the $1.05 tax imposedon each barrel of petroleum product imported into Hawaiʻi be deposited into the ESDSF. These
funds are intended to match funds from federal and private sources, and to award contracts or
grants for developing and deploying renewable energy technologies. (HRS Secs. 304A-1891-18942www.hnei.hawaii.edu

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and Sec. 304A-2169.1). In 2022, $0.03 (3 cents) per barrel of the ESDSF allocation was redirectedto the Hawaiʻi Public Utilities Commission (PUC) to support the development of EV
infrastructure.
Hawaiʻi’s energy transformation has been driven by bold state policies that now include a mandatefor 100% renewable electricity and carbon neutrality by 2045 (HRS Secs. 269-92 & 225P-5). A
core part of HNEI’s mission, going beyond traditional academic research, is to support Hawai‘i in
its clean energy transformation by helping facilitate cost effective and practical solutions to deliver
renewable energy for the state and its citizens. As part of this effort, HNEI robustly supports
analysis to inform energy policy and decision making in Hawai‘i.
The analysis conducted by
HNEI and its contractors is used by the utility and PUC in their decision making. HNEI also serves
as a critical bridge to Federal initiatives in supporting the State’s 100% renewable portfolio
standard and clean transportation initiatives. HNEI is recognized as an independent organization
providing trustworthy and practical information to support safe, reliable economic development of
renewable energy systems and technologies.
The foundation of HNEI’s strength lies in its people, its partners, and its contractors. The diversityof talents, education, experience, and entrepreneurial spirit of this team creates flexibility inperforming a range of renewable energy development and analysis activities. HNEI brings
together experts from a broad set of disciplines and organizations to develop solutions thatsignificantly impact energy transformation initiatives in Hawai‘i. HNEI coordinates closely with
the State Energy Office (formerly with the State Energy Coordinator), the Hawaiʻi Public Utilities
Commission (PUC), the state’s investor owned utility (Hawaiian Electric Company, HECO), andcommercial and industrial entities. HNEI has also successfully garnered extramural funding froma range of federal sources to maximize thevalue of state funds to meet needs andopportunities within the state.
HNEI
maintains strong working relationships withthe members of Hawaiʻi’s Congressionaldelegation and other government and nongovernment organizations in the Asia-Pacificregion. By engaging in a wide range of
disciplines and with a variety of stakeholders,
HNEI is able to tackle urgent and complex
clean energy needs of our State, the nation,and partners in the Pacific region.
To accomplish this mission, HNEI integrates analysis, research, engineering, economics, andscience to develop and demonstrate technologies, strategies, and policies that will significantly
impact energy transformation initiatives in Hawai‘i and beyond.

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2. HAWAI‘I NATURAL ENERGY INSTITUTE STAFFING/FUNDING OVERVIEWAs an Organized Research Unit in the School of Ocean and Earth Science and Technology at the
University of Hawaiʻi at Mānoa (UH), HNEI receives state funding via the Hawaiʻi General Fundthrough the university budget, sufficient to support its Director (Richard Rocheleau), threeadministrative support staff, and partial salaries (60% to 80%) of five tenure or tenure-track faculty(permanent faculty). HNEI has recently received approval to hire to additional tenure track faculty
expected to help support the state’s decarbonization goals. HNEI staffing for 2023 is summarized
in the Table 1 below.
Table 1. HNEI total staffing by position type for 2023.
STAFFING

Director: Richard E. Rocheleau
Permanent Faculty (FTE)
Other Permanent Staff (APT)
Temporary Faculty
Other Temporary Staff (a) (APT, RCUH)
Training (b)(a) Includes post-doctoral fellows

6
3
13
14
20
(b) Includes graduate andundergraduate students,and visiting scientists

As summarized in Table 2, HNEI’s primary source of funding is from extramural awards fromvarious federal agencies. In recent years, the majority of these funds have been from the Office ofNaval Research, the U.S. Department of Energy, and Naval Facilities Engineering Command, but
HNEI also receives funds from other U.S. Federal agencies and industry as well. A complete
breakdown of HNEI awards for FY 2021 through FY 2023 is shown in the Tables 3 through 5.
In addition to supporting the balance of HNEI’s permanent faculty, the extramural funds fromthese sources support temporary faculty and staff including engineers, scientists, and support
personnel as well as post-doctoral fellows, students, and visiting scientists within HNEI. Due tothe multidisciplinary nature of HNEI’s work, these extramural funds also support faculty, students,
and post-doctoral fellows in other departments and colleges.
HNEI also receives a small amount of tuition return. HNEI’s extramural awards also generate
indirect “Research and Training Revolving Funds,” of which approximately 25% is returned to
HNEI to facilitate operations and research. In addition to addressing national and international
needs, many of the projects funded by the entities identified above directly or indirectly support
Hawaiʻi’s clean energy goals.
As part of its responsibilities under Act 253, HNEI also administers the Energy Systems
Development Special Fund (ESDSF), allocated from the environmental response, energy, and4www.hnei.hawaii.edu

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food security tax (“Barrel Tax”) pursuant to HRS Section 243-3.5. Funding from the ESDSF
serves as an invaluable source of funding for HNEI. The primary uses of the ESDSF over the last
three years were to: 1) provide cost share to federally funded energy research when non-federal
cost share is required to secure the funds; 2) provide funds to address explicit PUC and legislative
requests, including unfunded legislative mandates; and 3) to support select community
engagement efforts, such as the annual Hawaiʻi Energy Conference and the Hawaiʻi Energy Policy
Forum, whose activities include the annual legislative energy briefing. Of the $2,308,000
encumbered or committed during FY21 to FY23, these three activities received $1,001,000,$514,000, and $293,000 respectively. The largest commitment, federal awards requiring costshare, leveraged many millions more in federal dollars that otherwise would not have beenprocured for Hawaiʻi use. An example is a pending, recently approved U.S. Department of Energy
award awaiting final signature at the UH Office of Research Services, in which $250,000 from the
ESDSF allowed HNEI to secure an additional $1 million of federal funds for advanced training in
microgrid relevant areas.
During FY21 to FY23, the remaining $500,000 ESDSF funds supported general management of
the ESDSF and was a major contributor to HNEI’s grid studies that supported the utilities, IGP
process, reliability studies associated with the retirement of the coal plant, a required assessmentof Hawaiʻi’s progress toward its Renewable Portfolio Standard goals and many other analysis of
future grid operations that have been presented to HECO and to the PUC. These activities are
generally cost shared via funding HNEI receives from the Office of Naval Research. Leveraging
the ESDSF in this way, amplifies the benefits for Hawaiʻi residents.
Generally, HNEI does not initiate legislation but, as evidenced by the project summaries in Appendices
A and B, HNEI projects do inform legislators and other Hawai‘i government organizations withunbiased information and analysis on matters relevant to pending issues, bills, and proposals whereappropriate. For example, HNEI provides a range of support to the PUC, including detailed analytic
studies for evaluation of utility proposals. HNEI is a longtime member and supporter of the Hawai‘i
Energy Policy Forum (HEPF), a collaborative energy planning and policy group comprising
approximately 40 representatives from business, academia, government, and non-profit
organization. In 2021, HNEI assumed responsibility for coordination of the HEPF activities. A
breakdown of HNEI funding by type for the past three fiscal years is shown in the Table 2 on thefollowing page, including the ongoing leveraging of the ESDSF.

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Table 2. Funding by source and year, FY 2021 to FY 2023*.
General Funds
Tuition and Fees S Funds
Extramural Awards
Research and Training Revolving
Energy Systems Development Special Fund

FY 2021$1,296,118$25,173$15,123,364$433,925$507,000

FY 2022$1,329,727$49,897$15,205,393$351,258$914,000

FY 2023$1,259,349$32,870$13,932,226**$445,870$887,000*ESDSF shows funds in year funds are committed or **Includes $8,388,656 approved by federal
encumbered. All others shown in year funds are agencies but awaiting final approval by UH Officeawarded.
of Research Services.

Table 3. Summary of HNEI Extramural Funding, FY 2021.
Office of Naval Research, Asia-Pacific Energy Systems
Office of Naval Research, Sustainable Energy Systems
NAVFAC, Wave Energy Test Site
U.S. Dept. of Defense, Sustainable Aviation Fuels
FAA, Sustainable Aviation Fuels$4,070,000$5,530,000$3,137,889$136,765$200,000

U.S. Dept. of Energy, Island Energy Resilience
U.S. Dept. of Energy, Grid Technology via Washington State University
U.S. Dept. of Energy, Wave Energy Conversion Development
U.S. Dept. of Energy, Marine Center Infrastructure$125,000$31,063$253,727$999,997

City and County of Honolulu, Energy Efficiency
SINTEF (Norway), Biocarbons
Trevi Systems, Battery Testing
Dept. of Defence (Australia), Battery Testing
Element Energy, Battery Testing
USAID, International via Tetra Tech

$119,000$35,189$50,000$204,033$170,669$60,032
FY 2021 Total

6$15,123,364

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Table 4. Summary of HNEI Extramural Funding, FY 2022.
Office of Naval Research, Sustainable Energy Systems
NAVFAC, Wave Energy Test Site
FAA, Sustainable Aviation Fuels$6,249,889$6,000,000$100,000

U.S. Dept. of Energy, Hydrogen Storage
U.S. Dept. of Defense, Sustainable Aviation Fuels
U.S. Dept. of Energy, Island Energy Resilience
U.S. Dept. of Energy, Wave Energy Conversion Development via OSU
U.S. Dept. of Energy, Grid Technology via UAF
U.S. Dept. of Energy, Grid Technology via WSU$710,304$88,201$105,000$63,898$190,732$6,564

State of Hawaiʻi - DAGS, Wave Energy Conversion Development$199,978USAID, International via RTI International
USAID, International via Tetra Tech
Delphos International, Grid Analysis
RTI International, Grid Analysis$92,039$10,869$34,952$310,233

Accure Battery Intelligence (Germany), Battery Testing
SINTEF (Norway), Biocarbons
National Science Foundation, Materials Research$239,941$2,793$800,000
FY 2022 Total

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Table 5. Summary of HNEI Extramural Funding, FY 2023.
Office of Naval Research, Fuel Cells
NAVFAC, Wave Energy Test Site
FAA, Sustainable Aviation Fuels$200,000$3,637,609$400,000

U.S. Dept. of Energy, Island Energy Resilience
U.S. Dept. of Energy, Thin Films and Printable PV
U.S. Dept. of Energy, Grid Technology via UAF$105,000$450,000$154,988

USAID, International via RTI International
Deloitte & Touche, International
Nuvera Fuel Cells, Fuel Cells$257,485$238,579$99,999
FY 2023 TOTAL$5,543,660

Pending UH ORS Approval
Office of Naval Research, Sustainable Energy Systems$4,600,000

U.S. Dept. of Energy, Durable Hydrocarbon FC Membranes
U.S. Dept. of Energy, MicroGrid Training
U.S. Dept. of Energy, Encapsulation of Perovskite Fuel Cells
U.S. Dept. of Energy, Power Systems, Dynamic Converter Systems
U.S. Dept. of Energy, 2D Materials for Solar Films$1,800,000$1,000,000$375,000$136,079$250,000

Sintef, Biocarbons
Element Energy, Battery Testing$27,399$200,178
Total Pending UH Signature$8,388,656

FY23 plus awards pending UH signature$13,932,316

3. RESEARCH SUMMARIESExtramural funds garnered by HNEI support programs across a broad range of technologies andend uses including: Energy Analysis of current and future energy systems; Grid Technology
Development; Alternative Fuels including sustainable aviation, biofuels, and hydrogen;
Electrochemical Power Systems including fuel cells and battery technology; Advanced
Materials, Ocean Energy, and an active and growing International presence.

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In 2023, within these areas, HNEI conducted or provided leadership for 58 discrete projects. Of
these 58 projects, approximately 35% are funded or co-funded by the ESDSF. The various
activities and key accomplishments under each of these projects are summarized in a series ofsummaries included within the nine Appendices of this report. These “Research Highlights”
summaries provide a concise description of active HNEI research projects in an easily accessible
format. Many contain links to more detailed reports, papers, and descriptions of HNEI’s work
activities that are also available on its website (https://www.hnei.hawaii.edu/). Updates to projects
are available on our website during the year. Sources of funding for each of the projects are also
identified within the summaries.
Brief summaries of what is included in each of the nine Appendices and a full listing of theircorresponding page numbers follows.
Appendix A: Hawai‘i Energy Analysis – Community Support
HNEI and its contractors conduct analysis across a broad range of issues. These are a result fromlegislation or more informal requests based on discussions with legislators or state agencies, withthe primary agency being the Hawaiʻi Public Utility Commission (PUC). They may also arise
from interactions with the utility, but only where they address broader state or PUC interests.
During this reporting period, the work has relied heavily on models and data developed by HNEI
and its primary consulting partner, Telos Energy. The focus of the efforts in this section tend to
be analyses related to more immediate problems facing Hawaiʻi’s electricity grids and policy
makers. The work described in Appendices A1 and A2 provide direct support to the Hawaiʻi
Public Utilities Commission, including HNEI’s recently submitted analysis of the state’s utility
companies’ progress toward the 2030 Hawaiʻi RPS goals. Appendix A3 describes work initiatedwith a legislative request to evaluate the disposal and recycle of clean energy products in Hawaiʻi.
Appendices A4 and A5 supported the utility’s IGP analysis and the Hawaiʻi Energy Policy Forum,
respectively. HNEI’s work with various energy communities are summarized in Appendices A6
and A7. Finally, Appendix A8 describes HNEI support of the Hawaiʻi State Energy Office(HSEO), including support of the state’s Powering Past Coal Taskforce.
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
As part of its work to support the state’s progress to achieve very high penetration of renewableenergy, HNEI and its contractors conducted a series of studies to assess the reliability of theislands’ grids as distributed rooftop solar and the pending utility scale solar + storage projects are
deployed. A series of studies involving Oʻahu and Maui are presented in Appendices B1 throughB4.

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Appendix C: Future Energy Systems
While conducting modelling in support of the state’s progress to achieve very high penetration ofrenewable energy, HNEI and its contractors identified a number of longer term issues andopportunities that are expected to have potentially significant impact on the reliability andoperations of Hawaiʻi’s electric grids. HNEI analysis has shown that the utilities can achieve very
high penetration of renewables using variable energy sources paired with the current 4-hour battery
technology. However, these studies also provided clear evidence that, at the highest penetrationlevels, some form of “firm” generation would be needed to provide grid services. In Appendix
C1, we identify the capacity of firm generation required for different levels of solar/wind/storage
penetration. Appendices C2 through C3 assess the potential for hydrogen or long duration storage
to meet these needs. Appendix C4 evaluates the impact of load shifting to reduce firm power
needs. Appendix C5 summarizes work to better understand the ventilation required to maintainsafe indoor work environments.
Appendix D: Grid Technology Development
With its very high penetration of distributed rooftop solar and the pending utility scale solar +storage projects, Hawai‘i is at the forefront of tackling the problem of renewable energy
integration. The geographic isolation of the islands’ electricity grids and the exponential growthof renewable generation make Hawai‘i’s electricity grids particularly susceptible to the effects ofintermittent and variable renewable energy sources, but also can serve as ideal test beds for energy
solutions for the nation. HNEI’s portfolio includes a range of grid technology development efforts,
ranging from development of new devices and methodologies to deployment and assessment ofemerging technologies to better understand their value. Funding for these projects includes the
Office of Naval Research and the U.S. Department of Energy, with projects of high relevance to
Hawaiʻi leveraged with funding from the ESDSF.
Appendices D1 through D7 summarize seven microgrid relevant technology development efforts.
These include: development and demonstration of a high efficiency DC microgrid at Coconut
Island; development of advanced conservation voltage reduction technology demonstrated at the
Marine Corps Base on Okinawa; continued development and demonstration of a virtual power
plant on Maui, a project focused on understanding the dynamic response of inverter dominatedpower systems; development and deployment of a bidirectional EV charging system on the UH
campus for optimized ride sharing; planning for EV charging infrastructure for USMC Camp Fuji
in Japan; and continued development of an advanced power systems laboratory.

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Appendix E: Alternative Fuels
Alternative fuels have always been an important component of Hawai‘i’s efforts to reduce its
dependence on imported petroleum and an essential component for reducing Hawaiʻi’s greenhousegas footprint. While early projects focused primarily on power and ground transportation
applications, sustainable aviation fuels are garnering increased interest in Hawaiʻi and nationally.
Within this topical area, HNEI conducts research, testing, and evaluation that seeks to support thepotential for alternative fuels production in Hawaiʻi. HNEI projects include two projects focusedon sustainable aviation fuels (Appendices E1 and E2), and one focused on enhanced fuels
characterization methodologies (Appendix E3). HNEI is also actively researching the productionof novel biocarbon materials using a slow pyrolysis process (Appendix E4), novel processes for
production of solar fuels with primary emphasis on photoelectrochemical hydrogen production(Appendix E5), and Appendix E6 provides an update to HNEI’s efforts to provide technicalsupport and fuel (hydrogen) for several electric-fuel cell hybrid buses to be operated by the HawaiʻiIsland Mass Transit Agency (Hele-on bus).
Appendix F: Electrochemical Power Systems
HNEI has been conducting research, development, and testing of fuel cell and battery technologies
for over two decades. The primary goal of these efforts has been to understand the performanceand durability of these electrochemical technologies for both commercial and military
applications, including fuel cell powered and electric vehicles, fuel cell powered unmanned(autonomous) aerial and undersea vehicles, and for grid services. Appendix F summarizes the ten
distinct projects HNEI conducts in this area. Appendix F1 summarizes HNEI’s ongoing
partnership with the Naval Research Laboratory to develop reliable fuel cell power systems forunmanned aerial vehicles. Appendices F2 through F7 describe multiple approaches fordevelopment of more efficient, lower-cost fuel cells, including both proton-exchange and anionexchange membrane technologies. Appendices F8 through F10 describe three projects focused
intended to inform the use of Li-ion energy storage systems. More detailed descriptions of eachof these efforts are found in Appendix F.
Appendix G: Advanced Materials
The seven projects included in the Advanced Materials group, include three projects focused on
the development of novel techniques for the production of thin-film materials for electronic andsolar application low cost photovoltaics (Appendices G1 through G3); one project focused on thedevelopment of low cost, high performance hydrogen storage technologies (Appendix G4); an
ongoing effort to develop novel solutions for forward osmosis seawater desalination (AppendixG5); and a description of a research and education collaboration with the University ofWashington, funded by the National Science Foundation (Appendix G6), and an fundamental

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research project to design and develop advanced air filtration materials for energy applications(Appendix G7).
Appendix H: Ocean Energy
Since 2015, HNEI has been engaged in a cooperative effort between the U.S. Navy and U.S.
Department of Energy to support testing of pre-commercial wave energy conversion devices in areal-world operational setting offshore from Marine Corps Base Hawai‘i. This site, still thepremier open water test site in the U.S., continues to be an invaluable resource for developers
needed to test prototype systems in a real world environment. Appendix H1 summarizes progress
to date and future plans for this site. More recently, HNEI has received an award from the U.S.
Department of Energy to develop its own wave energy technology. The proposed technology anddevelopment plans are summarized in Appendix H2.
Appendix I: International Support
In 2017, HNEI was the recipient of a multimillion-dollar award from the Office of Naval Research(ONR) titled “Asia-Pacific Regional Energy Systems Assessment (APRESA),” intended tofacilitate development of clean, resilient, and efficient energy systems throughout the Asia-Pacificregion. HNEI has leveraged this initial ONR funded effort to develop a wide range of partnershipand new funding sources derived from USAID and World Bank programs. Appendix I1 provides
an overview of the APRESA award and very brief summaries of a number of projects under thisaward, including ones in Vietnam, Thailand, Indonesia, Cambodia, and the Philippines.
Appendices I2 and I3 provide additional detail for two of the many projects initiated under
APRESA. Appendices I4 through I7 summarizes the recent work supported by USAID and theWorld Bank (via subcontracts to the prime) that took place across the Asia-Pacific region,
including in Papua New Guinea, the Philippines, and Indonesia. Appendices I8 and I9 summarize
other island specific studies in the Asia-Pacific region and Caribbean, respectively.

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APPENDICES
Appendix A: Hawaiʻi Energy Analysis – Community Support
15 A1: Decision Support Services to the Hawaiʻi Public Utility Commission
17 A2: Evaluation of the State Renewable Portfolio Standards Mandate
20 A3: Disposal and Recycling of Clean Energy Products in Hawai‘i
21 A4: Support of Integrated Grid Planning
24 A5: Hawai‘i Energy Policy Forum
26 A6: Molokaʻi Community Energy Resilience Action Plan
27 A7: Energy Transition Initiative Partnership Program
29 A8: Hawaiʻi State Energy Office Support
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
31 B1: Oʻahu Near-Term Grid Reliability with AES Retirement
34 B2: Maui Near-Term Reliability and Kahului Retirement Analysis
37 B3: Oʻahu Retirement Study
40 B4: Oʻahu and Maui Load Flexibility
Appendix C: Future Energy Systems
43 C1: Clean Firm Needs
47 C2: Hawaiʻi Hydrogen Integration Study
50 C3: Long Duration Storage Modeling
52 C4: Analysis of Bill Impacts and Equity of Time-of-Use Rate Design
55 C5: Modeling and Validating Indoor Air Quality in Hawaiʻi Classrooms
Appendix D: Grid Technology Development
56 D1: Coconut Island DC Microgrid
57 D2: Advanced Conservation Voltage Reduction Development and Demonstration
58 D3: Hawai‘i Virtual Power Plant (Hi-VPP) Demonstration
59 D4: Assessing Dynamic Response of Converter‐Dominated Power Systems
60 D5: Bidirectional EV Charging Demonstration Project
61 D6: EV Charging Infrastructure Master Plan for USMC Camp Fuji, Japan62 D7: Advanced Power Systems Laboratory (APSL)Appendix E: Alternative Fuels
63 E1: Sustainable Aviation Fuel Production
73 E2: Investigation of Waste-Based Feedstocks for Sustainable Aviation Fuel Production
75 E3: Advanced Fuel Characterization and Development
77 E4: Novel Biocarbons
78 E5: Solar Fuels Generation
80 E6: NELHA and MTA Hydrogen Stations and Fuel Cell Electric Buses

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Appendix F: Electrochemical Power Systems
84 F1: Contaminant Tolerant Fuel Cells for Harsh Environments
86 F2: Anion Exchange Membrane Fuel Cell
87 F3: Transition Metal Carbide Catalysts for Electrochemical Applications
88 F4: Materials Enablers for Advanced Manufacturing of Attritable Fuel Cells
89 F5: Proton Conducting Electrolytes for HT-PEMFC
91 F6: Advanced Characterization of PEMFC with Open Flow Field Architecture
92 F7: Proton Exchange Membrane Fuel Cell Producing Hydrogen Peroxide
94 F8: Path Dependence of Battery Degradation
96 F9: Battery Intelligence: Diagnosis and Prognosis
99 F10: Battery Electrode Optimization
Appendix G: Advanced Materials
101 G1: Printable Photovoltaics
102 G2: Two-Dimensional Materials for Thin Film Manipulation
103 G3: Encapsulation of Perovskite Solar Cells for Long Term Operations
104 G4: Develop Reversible Liquid Hydrogen Carriers Containing Magnesium Boranes
106 G5: Forward Osmosis Draw Solutions for Seawater Desalination
107 G6: UH and UW Materials Research and Education Consortium (MRE-C)
109 G7: Development of Novel Air Filtration Materials
Appendix H: Ocean Energy
110 H1: Research Support to the U.S. Navy Wave Energy Test Site
113 H2: The Hawaiʻi Wave Surge Energy Converter (HAWSEC)
Appendix I: International
115 I1: Asia Pacific Regional Energy System Assessment (APRESA)
120 I2: Saigon Energy Hub (SEHub) Support
121 I3: Provincial Electricity Authority of Thailand (PEA) Collaboration
122 I4: USAID Papua New Guinea Electrification Partnership (PEP) Activity
123 I5: Support to the USAID Energy Secure Philippines (ESP) Program
124 I6: USAID Sustainable Energy for Indonesia’s Advancing Resilience Program
125 I7: USAID South East Asia’s Smart Power Program – Laos
126 I8: Energy Systems Regulatory and Technical Support for Pacific Island Countries
127 I9: Energy Security and Resilience in the Caribbean Islands

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Appendix A: Hawaiʻi Energy Analysis – Community Support
A1: Decision Support Services to the Hawaiʻi Public Utility Commission
OBJECTIVE AND SIGNIFICANCE: HNEI provides
regular technical analysis and assistance to the
Hawaiʻi Public Utilities Commission (PUC). This
support provides ongoing review of utility plans andtechnical challenges faced by the electricity grid
during the transition to higher renewable energy. By
providing an unbiased, technical review of utility
plans and grid challenges, HNEI has established itself
as a trusted third-party in ongoing dockets and policy
discussions.
BACKGROUND: The PUC is the regulatory bodytasked with reviewing and deciding on investment
decisions, rates, and long-term planning of Hawaiʻi’s
investor owned utility, Hawaiian Electric Company(HECO). They are also tasked with reviewing thereliability of the electric power system and its
customers. At any point, there may be dozens of
dockets under review by the Commission, many ofwhich are based on highly technical and detailed
analyses.
The topics under review by the PUC are diverse andmulti-faceted. In the past, the PUC has been shortstaffed and does not have access to the same modelingtools and skillsets typically deployed by the utility for
their long-term planning and docket filings. As aresult, having the ability to draw on the expertise of
HNEI, and their contractor Telos Energy, provides
independent third-party technical expertise toaugment the analyses being conducted at theCommission. The flexible nature of this support
ensures that work can be deployed in a timely and low
cost manner relative to the use of other third-party
consultants. This collaboration with HNEI provides aflexible option to quickly analyze both near-term andlong-term questions posed by the Commission.
Examples of past support included a review of
HECO’s distributed energy resources (DER) Grid
Service definitions [Docket #2019-0323], theeconomic merits of HECO’s standalone battery
proposals [Docket #2020-0136], and benefits andchallenges of biomass conversion for the AES coalplant [Docket #2021-0024].

This paper briefly discusses four recent examples of
HNEI support to the PUC. These are also describedin more detail in other project summaries located inthis report.
• AES retirement and replacement;• Maui oil unit retirement and replacement;• Firm renewable needs; and• Time of use rates and equity.
PROJECT STATUS/RESULTS: The HNEI-Telos team
met with the Commission in person in January 2023
to discuss ongoing developments at the utility, HNEI
analysis, and other critical issues for the state.
AES Retirement and Replacement (Appendix B1):
The AES Hawaiʻi coal plant, the largest power planton Oʻahu retired on September 1, 2022. Thisretirement decreased the amount of dispatchable
fossil capacity available to the utility by more than
10%. Throughout 2021 and 2022, the HNEI-Telos
Energy team routinely conducted reliability analysisof the retirement to brief HECO, the PUC, and theGovernor’s Power Past Coal Task Force on theimpacts of project delays, cancellations, and otherevents [Docket #2021-0024]. The objective of thisongoing study is to evaluate the ability of proposed
solar + storage resources to provide the requiredenergy needed while also maintaining grid reliability
with the pending AES coal plant retirement. The
results of this work are expected to have important
implications for power system planning and policy
for Oʻahu.
Stochastic analysis, using the tools developed by the
HNEI-Telos Energy team and reported last year, arebeing used to assess capacity reliability risks
associated with the AES retirement, updates forutility plans, and possible impacts due to delays inproject schedules, and new trends in HECO’s
generator outage rates (-), the recent failure of Kahe
4 (-), project delays (-), and load (+). Analysis showsthat with the retirement of AES in September with
only one replacement resource available (Mililani I,
39 MW). In 2023, an additional resource was brought
online (Waiawa I, 36 MW), but challenges incommissioning and testing the KES standalone
battery have continued to challenge Oʻahu reliability.
Fortunately peak levels on Oʻahu continue to trendwell below pre-pandemic levels. Oʻahu, however, iscurrently in a supply deficit until the KES plant is

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

15brought online or other Stage 1 and 2 solar + storage
resources become available.

can be with variable renewable energy and storagealone.

Maui Oil Unit Retirement and Replacement(Appendix B2): The Kahului Power Plant (KPP) is
scheduled to retire by the end of 2024. Analysis in
2021 showed how the retirement could be reliably
achieved with proposed solar + storage projects.
Since that analysis, project delays have occurred withreplacement resources. In addition, the Māʻalaea
M10-M13 diesel engine may need to be retired earlier
than expected. The combined retirements would
represent the loss of over 85 MW of firm capacity,
over 40% of Maui’s peak demand.

In 2023, HNEI expanded that analysis to consider
specific resources that could provide the firm
renewable needs, including biodiesel, hydrogen, andmulti-day energy storage. As specific projects are
considered in the Stage 3 Firm Renewable RFP[Docket #2017-0352] – the results of which are
expected by the end of 2023, HNEI will review
proposals and provide recommendations and analysis
to the Commission upon request.

Similar to the work conducted in Oʻahu, the objectiveof this study was to update the 2021 analysis andreevaluate Maui’s reliability if one or both of theplants are retired and evaluate potential mitigations
necessary. The results of this analysis were briefed to
the PUC [Docket #2021-0024] and the Maui
Accelerating Clean Energy & Decarbonization
Technical Working Group (ACET) and are expected
to have important implications for power system
planning and policy for Maui.
The HNEI-Telos team continues to monitor ongoingdevelopments in Maui, including the status of Stage 1
and Stage 2 project commissioning, adoption of DER
and BTM storage, peak load levels, and generator
reliability. While the M10-13 plants are expected toremain available for 4-5 more years, any new capacity
additions beyond those under development in Stage 1
and 2 will likely take that much time or longer. As aresult, HNEI will continue to support the Commission
with independent reviews of Maui reliability.
Clean Firm Needs (Appendix C1): HNEI conducteda study to inform ongoing procurement and proposed
legislation for both variable and firm renewableenergy. It sought to determine the minimum amountof firm power that the system would require at various
levels of wind, solar, and storage additions. It also
informed decisions on whether to integrate morevariable renewable energy today, considering thatthese decisions may shut the door on future options.
This information can be used to determine
characteristics of future systems to inform decisions
on oil-fired power plant retirements, procurement of
new resources, and to show how robust the system

Time of Use Rates and Equity (Appendix C4): In
2023, there were two notable developments at theCommission. The first was the acceptance of HECO’s
proposed time of use (TOU) rates [Docket #20190323] and a new docket and priority afforded tocustomer equity [Docket #2022-0250]. To support theCommission in their review of these priorities, the
HNEI-Telos team conducted a TOU Rate analysis.
This work included a review of HECO’s AMI data tocalculate changes to bill payments with and without
the new TOU structure. This analysis quantified bill
impacts ($ and %) across a sample of several
thousand HECO ratepayers using actual, 15-minuteinterval consumption data. This analysis also allowed
the study to calculate changes in revenue for theutility and the potential for costs to shift from TOU
early adopters to other ratepayers and current solar
customers. This raises concerns over equity becausesome lower income ratepayers may not be able toadopt new technologies to benefit from load shifting
and TOU rates.
As the regulatory priorities in Hawaiʻi continue toshift, HNEI will support ongoing analysis andrecommendations to ensure a fair, cost-effective,
renewable energy transition for the state. In 2024,
HNEI anticipates supporting a review of the Stage 3
RFPs, ongoing reliability concerns, and further
support for land use and equity concerns.
Funding Source: Energy Systems Development
Special Fund; Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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16

Hawaiʻi Natural Energy Institute Research Highlights

Appendix A: Hawaiʻi Energy Analysis – Community Support
A2: Evaluation of the State Renewable Portfolio Standards Mandate
OBJECTIVE AND SIGNIFICANCE: The State of
Hawaiʻi’s (“State”) energy policy is driven, in
significant part, by the State’s Renewable Portfolio
Standards (RPS) that mandate the percentage ofelectricity that must be generated from renewableenergy resources at different times until achieving
100% in 2045. The RPS targets have evolved throughseveral legislative amendments since the RPS was
first established in 2001. The current RPS, under §269-92, Hawaiʻi Revised Statutes (HRS), wasmodified by ACT 140 of the 2022 legislature
requiring electric utilities in the State to reportelectricity from renewable sources based on apercentage of electricity generation including
distributed generation.
HNEI is required by legislation to provide regular
technical analysis and assistance to the Hawaiʻi
Public Utilities Commission (PUC). As part of thisassistance, HNEI provides the PUC with an update of
the status of the RPS every five years. This year’s
analysis report is the fourth that HNEI has performed
since 2008. HNEI’s analysis is used by the PUC in
the development of their report to the legislature.
BACKGROUND: Hawaiʻi’s RPS is intended topromote Hawaiʻi’s energy policy goals byencouraging the development and implementation of
locally-sourced renewable energy generation
connected to Hawaiʻi’s utility electricity systems,
resulting in the displacement of existing fossil fuelgeneration and reducing the State’s dependence on
imported oil. The PUC is required by statute toevaluate Hawaiʻi’s RPS every five years and reportits findings to the Legislature. The objective is todetermine if the standards established by HRS § 26992 remain effective and achievable based on progress
to date and to analyze options for meeting RPS targets
in the future. Hawaiʻi’s initial RPS was established in2001 (Act 272, Session Laws of Hawaiʻi 2001). The
most recent modification to the RPS occurred in July
2022. Act 240 (HB 2089) was signed into law thatamended the RPS calculation from renewable energy
as a percentage of sales to renewable energy as apercentage of total system generation. The new
calculation is based on total generation (including
generation from private rooftop solar, in the
denominator) and total renewable generation(including generation from private rooftop solar, inthe numerator). The current RPS goals, by year, aresummarized in Table 1.
Table 1. Hawaiʻi’s Renewable Portfolio Standards by year.

Compliance
Year
2010
2015
2020
2030
2040
2045

RPS Requirement(% of Generation)
10%
15%
30%
40%
70%
100%

PROJECT STATUS/RESULTS: The RPS is applied
separately to Kauaʻi Island Utility Cooperative(KIUC) and Hawaiian Electric Company (HECO). In
performing the analysis necessary for this Report, the
HNEI relied on several sources of information
including:• Annual Utility RPS Status Reports: Each of
Hawaiʻi’s electric utilities provides annual
reports identifying the amount of energy
generated by renewable sources and theachievement of the RPS requirements. These
reports identify renewable generation resourcesthat are operating as of the dates of the reporting
periods. The Commission relies on these reports
to quantify historical and existing renewableenergy generation. The most recent reports byeach utility indicate RPS achievement
information for the calendar year 2022.
• Future Renewable Generation Projects: This
includes new renewable generation projects thatprovide electrical power to each utility. Expected
renewable generation for these projects isprovided by the utilities, based on current
estimates. The Commission relies in this Reporton approved applications to quantify expected
renewable energy generation from projects thatare under construction or substantially inprogress. In addition, for the HECO Companies,
the ongoing competitive-bid process for new
renewable generation includes information
regarding the possible scope of new renewable
resources in the near- to-mid-term. For HECO,
more than 500 MW of renewable projects are
expected to come online in the next few years.
• Mid- and Long-Range Utility Planning
Estimates: Hawaiʻi’s electric utilities also

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17

provide the Commission with mid-term and longrange planning information and projections of
expected and possible capital expenditures in
filed reports, periodic briefings, and theIntegrated Grid Planning (IGP) process. Planning
information includes identification of possible
specific future renewable generation projects,
possible requests for proposals, and generalestimates of possible resource potential.
• Additional Expert Opinion: External expert
opinion was also factored into the analysis andcommentary. A number of anonymized statebased experts were interviewed to obtain theirviews on the future achievement of RPS goals.
These experts including those from nongovernmentalorganizations(NGOs),
independent power producers, the utilities,
academia, and state agencies.
Key findings in HNEI’s 2023 Report include:• Achievement of the 2030 RPS requirement of
40% is likely for HECO service territory, which
includes Oʻahu, Maui County, Hawaiʻi Island,
and is essentially certain for KIUC. As of 2022,
KIUC has already achieved the 2030 goal.
• Based on current plans for the PUC approved
Stage 1 and Stage 2 PV plus storage projects, theHECO territory is expected to reach the 40% by2030. However, force majeure and related supply
chain issues have created problems for State 1
and Stage 2 projects. If these issues continue, it
could create problems in achieving the 40%
mandated goal. Additionally, the recent Lahaina
wildfires could potentially impact the pace of
new renewable energy generation on Maui.
• The RPS has led to a substantial reduction ofGreenhouse Gases (GHGs) being emitted in theelectricity sector. However, GHGs have notdiminished significantly in other sectors(transportation, buildings, etc.) as much as the
Hawaiʻi Clean Energy Initiative (HCEI)
originally projected.
• Increasing electric loads from electric vehicle
adoption will make it more difficult to achieve the
RPS targets in the future, but will ultimately
benefit statewide emissions.
• The costs of renewable energy projects underdevelopment and recently proposed in Hawaiʻi
remain at or below costs of oil-fired generation,
making renewable projects cost-competitive

alternatives compared to continuing to utilize
fossil fuel generation resources. However, recent
events including delays in the development of
HECO Stage 1 and 2 projects have led toincreased costs for renewable energy
development and deployment.
• Initial analysis by HNEI to explore the ability tointegrate solar plus storage or solar/wind andstorage suggests that reaching the 70% RPStarget by 2040 is feasible and likely cost effectivewith current technologies. However, land use,
community engagement, and transmission willneed to be carefully managed.
• The RPS remains effective in helping the State
achieve its policies and objectives with respect todeveloping renewable energy resources in
Hawaiʻi.
However, it should be noted that in 2022, whilecustomer-based generation was the largest single
source of renewable energy at the end of the year, theadvances in the development of utility-scale
renewable generation have been significant since the2018 assessment. Figure 1 is a pie chart showing therelative percentages of resources providing electricity
from renewables statewide.

Figure 1. Percentages of renewable resources andtechnologies providing electricity for Hawaiʻi.

Figure 2 shows progress against the RPS by Island.
The Report provides additional detail for the KIUC
and HECO service areas. The downturn evident for2022 is due to the new method required for estimationof the renewable fraction which is now based on total
generation, not just utility sales.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

18While the outlook for meeting the 2030 goals is
excellent, the Report notes a number of concerns
about meeting the future RPS mandated goals (70%in 2040 and 100% in 2045). This concern is due to avariety of factors. These include issues concerning
reliability and resiliency, land availability(particularly on Oʻahu), local community acceptance,transmission interconnections, the demand increased
electrification of transportation and buildings willplace on the RPS, and uncertainties regarding the
emergence of newer technologies and resources tomeet the expected need for dispatchable firm power
to maintain reliability. A more complete discussion
can be found in HNEI’s Report to the PUC.
Funding Source: Energy Systems Development
Special FundContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Figure 2. Consolidated progress in meeting RPS goals by Island.

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19

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A3: Disposal and Recycling of Clean Energy Products in Hawaiʻi

OBJECTIVE AND SIGNIFICANCE: Hawaiʻi’s pursuit
to become fully renewable by 2045 will produce
substantial streams of clean energy waste over the
next 30 years and beyond. In recent years, Hawaiʻi
has seen large growth in the use of solar photovoltaic(PV) panels. This is expected to continue with new
systems, both rooftop and utility scale, combined withbattery energy storage systems. Due to this, it is
crucial for the state to manage these waste streams ina manner that is both safe and environmentally sound.
The objective of this work is twofold: 1) to quantify
this waste stream and best practices for their costeffective recycle and 2) to conduct a comprehensive
technical assessment to determine best practices for
disposal, recycling, or secondary use of clean energy
products produced in the State.
BACKGROUND: The 2021 Hawaiʻi State Legislature
passed House Bill 1333 which required that the
Hawaiʻi Natural Energy Institute, in consultation with
the Hawaiʻi State Department of Health, conduct athorough study on best practices for disposal andrecycling of discarded clean energy products in
Hawaiʻi. Specific deliverables addressed were: 1) theamount of PV and solar water heater panels in theState that will need to be disposed of or recycled; 2)other types of clean energy materials expected to bediscarded in the State including glass, frames, wiring,
inverters, and batteries; 3) the type and chemicalcomposition of those clean energy materials; 4) bestpractices for collection, disposal, and recycling of
those clean energy materials; 5) whether a fee should
be charged for disposal or recycling of those clean
energy materials; and 6) any other issues the HawaiʻiState Energy Office and Department of Healthconsider appropriate.
PROJECTSTATUS/RESULTS:
This
project,
commenced in September 2021, remains ongoing.
Findings to date include: 1) identifying material
composition of PV panels, inverters, cabling, andmounting equipment as a function of installed power(kg/kW); 2) quantifying the cumulative PV installedby island for residential, commercial, and utility scale
since 2005; 3) calculating the projected loading rateof aging PV materials as far out as 2045; 4)
determining the preliminary estimates of installedbattery capacity at residential, commercial, and utility
scale; 5) evaluating estimates of material compositionof PV battery as a function of installed power(kg/kW); 6) conducting a comprehensive assessmentof waste treatment options, costs, and risks; and 7)
conducting a comprehensive assessment of fee
options and recommendations. Specifically:
1. As of 2021, it is estimated that 3.86 million
modules have been installed on Oʻahu, 720,000
in Maui County, 580,000 in Hawaiʻi County, and480,000 on Kauaʻi. A total of 225,000 tons of PV
related clean energy materials have been
installed in Hawaiʻi through 2021. For context,
the total amount of municipal solid waste andcommercial/demolition waste generated in theState during 2021 was 2,570,478 tons. The total
amount of these PV related clean energy
materials installed to date totals 8.8% of allmunicipal
solid
waste
and
commercial/demolition waste generated acrossthe entire State in 2021.
2. The cost of disposing PV panels and Li-ion
batteries will require one or more revenuegenerating schemes to be established; potentially
including waste generator responsibility,
extended producer responsibility, state assisted
recycle, and state encouraged recycle. The
recommendation is to establish a process thatcovers the full price of their off-island disposal.
3. The possibility of enhanced restrictions orbanning of ocean shipping of end-of-life Li-ion
batteries was identified as an existential threat to
Hawaiʻi’s disposal of these products.
4. To address this threat, the need to deactivate Liion batteries or even fully recycle Li-ion
batteries on island was identified in order toensure long term access to ocean transport.
These and other results have been detailed in HNEI’s
report “Recommendations on Waste Management ofClean Energy Products in Hawaiʻi,” which waspreviously submitted to the legislature. Although notmandated, this work was continued in 2022 to add
depth to policy recommendations for the disposal andrecycling of clean energy materials in Hawaiʻi and a
supplemental report was produced and is available
on HNEI’s website.
Funding Source: Energy Systems Development
Special FundContact: Michael Cooney, mcooney@hawaii.edu
Last Updated: November 2023

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20

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A4: Support of Integrated Grid Planning

OBJECTIVE AND SIGNIFICANCE: In 2018, underguidance from the Hawaiʻi Public Utilities
Commission (PUC), the Hawaiian Electric Company(HECO) initiated the Integrated Grid Planning (IGP)
process to determine the types of resources and grid
services the utility should invest in over the coming
years to meet the goals of legislatively mandated
Renewable Portfolio Standards. A TechnicalAdvisory Panel (TAP) was established to provide a
third-party, technical, and unbiased review of
HECO’s modeling and analysis efforts to ensure thatbest tools and methodologies are being used. The
TAP consists of experts from around the country
including members from National Laboratories,
industry groups and other utilities. Based on direction
from PUC Order No. 36725, Providing Guidance on
the IGP, HNEI chaired the IGP’s TAP from its
inception in 2018 to October 2021 and continued tostay engaged in the TAP throughout 2022 and 2023.

have included advice in regard to the suite of tools
and process for integration of those tools andmethodologies. HNEI and its subcontractor Telos
Energy developed a modeling framework (Figure 1)
that was adopted as the IGP modeling framework by
HECO.
In
addition,
HNEI
providedrecommendations to identify “bookends” to delineate
the potential impacts of load uncertainty. During2021, significant effort was expended by HNEI toquantify alternative probabilistic methodologies andmetrics other than energy reserve margins (ERM),
with the potential for enhanced insights,
indetermining resource adequacy. These probabilistic
tools were used in the analysis of grid reliability withthe pending AES coal plant retirement.

KEY RESULTS: HNEI’s involvement in the IGP and
its previous leadership role in the TAP helped ensurethat HECO is moving forward in addressing gridissues related to increasing amounts of renewableenergy, which includes both distributed behind-themeter (BTM) generation, utility-scale generation, andutility-scale and BTM storage. The TAP provides
HECO with independent and technical oversight fromoutside experts, helping ensure that the utility is using
industry-accepted methods, inputs, and assumptions.

BACKGROUND: By Order No. 35569, issued on July12, 2018, the PUC opened the instant docket toinvestigate the IGP process. (Docket #2018-0165,
Instituting a Proceeding Order No. 30725 To
Investigate Integrated Grid Planning.) Pursuant toOrder No. 35569, the Companies filed their IGP
Workplan on December 14, 2018. The Workplan
described the major steps of the Companies' proposed
IGP process, timelines, and the methods theCompanies intend to employ, including various
Working Groups. On March 14, 2019, the PUC issued
Order No. 36218, which accepted the Workplan andprovided the Companies with guidance on its
implementation.

Key activities of the TAP have focused on assisting
HECO in revising their approaches to analysis. These

Following an initial period in which the progress of
the IGP did not fully meet expectations, HNEI was,Figure 1. HNEI modeling framework adopted by the IGP.
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21

in 2020, requested to assume an expanded role insupporting the IGP initiative. This increased support
included re-constituting the TAP membership,
working with HECO staff to revise their approach for
TAP meetings, and assistance in the review ofpresentation materials to ensure that meetings are aseffective as possible. In addition, due to issues thathave arisen in Working Groups and with the
Stakeholder Council, HNEI took an expanded role inparticipating in all of these activities.
This approach was confirmed by the PUC request to
HECO for the TAP to play a more substantive role inadvising HECO as it moves forward with its
integrated grid planning activities and confirmed in a
May 2020 letter from HECO to the PUC.
Through its November 2020 IGP Commission
Guidance, the PUC noted that, “[f]or the stakeholder
process outlined in the Workplan to effectively serve
as a replacement for independent evaluation, theTechnical Advisory Panel would have to take anactive role in analyzing, evaluating, and providing
public feedback on Working Group activities andReview Point filings.” The PUC continued by stating
its expectation that the Companies “use the TechnicalAdvisory Panel to provide independent review of
each Review Point filing that the Companies will
file.” While noting this more substantive approach,
the TAP is an independent advisory group and is nota decision-making body, but provides input andadvice on the methods and processes that theCompanies use to perform such work. HNEI’s
chairmanship of the TAP operated under these newprinciples through October 2021 when a new Chair
was selected. HNEI continues to play a very activerole in all aspects of the IGP process and TAP.
PROJECT STATUS/RESULTS: HNEI’s role as the
TAP Chair ended in early 2022. Despite no longer
chairing TAP, HNEI and their contractor Telos
Energy continue to be actively engaged as a memberin the TAP as well as other parts of the IGP
stakeholder process, including active involvement in
the Stakeholder Committee, the Stakeholder
Technical Working Group, and relevant TAP
subgroups.
In 2022, HNEI and its contractor, Telos Energy,
raised numerous concerns and corrective

recommendations about the excessive use of thecapacity expansion model, RESOLVE, in evaluating
impacts and implications related to its use incharacterizing reliability and grid service needs.
HNEI has demonstrated that these types of analyses
should be done in tandem with probabilistic analyses
that can be used to measure grid reliability from theuse of RESOLVE.
As a result of these recommendations, HECO adopted
HNEI’s probabilistic analysis framework at the endof 2022 and throughout 2023. Now included in all of
the IGP filings as well as HECO’s RFP is a
probabilistic framework that quantifies the loss ofload probability across different future resource mix
years and procurement cycles. It considers the impactof forced outages, load variability, and weather
impacts on solar and wind resources.
Throughout 2023, HNEI and Telos Energy actively
engaged in the TAP’s Transmission sub-committee,
and the Resource Adequacy sub-committee.
Considerable attention was paid to the Energy
Reserve Margin, HECO’s novel approach toresolving challenges associated with the planningreserve margin (PRM) commonly used across thepower industry. Based on written feedback andrecommendations the Commission ordered HECO to
conduct a third-party led study to evaluate different
options for PRM and ERM methodologies in
Hawaiʻi. In 2023, HECO engaged with theirconsultant (E3) and conducted the ordered study.
Throughout this process, HNEI and Telos Energy
provided numerous recommendations, writtencomments, and several discussions with the HECO
and E3 team to provide recommendations.
The IGP culminated in 2023 and ended a multi-year
process to lay out HECO’s long-term plan to reaching
100% renewable energy by 2045 as well asintermediate goals. The final IGP was filed with theCommission on May 12, 2023 and HNEI and the TAP
filed 111 public comments during the review process.
The IGP is currently under review by theCommission.
In parallel to the Commission review, HECO iscontinuing its competitive solicitation process via theStage 3 RFP. HNEI and Telos Energy have provided
both the Commission and HECO feedback on thisHawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
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22

RFP and are awaiting notification of the selected
projects. At that time, the HNEI-Telos team will
review proposed projects and may conduct
independent reviews of modeling and analysis if
requested.
As the IGP continues into its next phase, the HNEI
team will continue to provide technical and unbiased
review and recommendations for HECO’s long-termplanning and procurement process to ensure that theState can achieve its ambitious renewable energy
policy in an efficient and reliable manner.
Funding Source: Energy Systems Development
Special Fund; Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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23

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A5: Hawaiʻi Energy Policy ForumOBJECTIVE AND SIGNIFICANCE: Through thisproject, HNEI supports and manages the Hawaiʻi
Energy Policy Forum (HEPF) in its mission toadvance Hawaiʻi’s energy transition through energy
stakeholder engagement in fact finding, analysis,
information sharing, and advocacy that enables
informed decisions.
BACKGROUND: The HEPF was established in 2002
by the University of Hawaiʻi’s College of Social
Sciences (CSS) Public Policies Center (PPC) as acollaborative energy planning and policy groupconsisting of Hawaiʻi’s electric utilities, oil andsynthetic natural gas suppliers, environmental andcommunity groups, renewable energy industry,
academia, and federal, state, and local government. In
its first five years, the Forum was instrumental inpromoting funding and needed reform for the State’s
utility regulatory agencies (i.e., the Public Utilities
Commission (PUC) and the Division of Consumer
Advocacy), and commissioned studies, reports, andbriefings to raise the level of dialog concerningenergy issues for legislators and the general public.
The Forum has, in past years, sponsored andorganized Legislative Briefings at the Capitol at the
opening of each legislative session, an annual
Hawaiʻi Clean Energy Day event, and sponsors
programs to develop reliable information and educate
and raise awareness in the community. Among its
members, HEPF has more than 75 representatives
from the electric utilities, oil and natural gas
suppliers, environmental and community groups,
renewable energy industry, academia, and federal,state and local government all working together toseek smart energy solutions to sustain a healthy
prosperous, and secure Hawaiʻi.
The Forum’s mission is to share ideas andinformation, recommend and advocate policies andinitiatives, and promote civic action to achieve a cleanand sustainable energy future for Hawaiʻi. To thisend, it conducts research, briefings, forums for
informative and deliberative dialogue and policy
development, annual legislative briefings, andoutreach and public education. HEPF also produces
the biweekly “Hawaiʻi: State of Clean Energy”
production, streamed on ThinkTech Hawaiʻi(https://thinktechhawaii.com/), and made available
on the HEPF website.

PROJECT STATUS/RESULTS: In 2021, the CSS PPC
was eliminated by the University of Hawaiʻi andmanagement of the HEPF program was assumed by
HNEI. HEPF held the 2022 Legislative Briefing on
Friday, January 28th. The theme of the Legislative
Briefing was focused on gaps in Hawaiʻi’s energy
infrastructure and how the $1.2 billion Infrastructure
Investment and Jobs Act signed by President Biden
on November 15, 2021 could be used to address themost vulnerable aspects of that infrastructure.
In 2022, the HEPF took the following actions:• Creation of online informational resources formembers and the public focusing on compilationof the significant new federal policies related toenergy which includes a description of the policy,
policytype,
relevant
sector,funding
opportunities, and managing agency. Initially,
this featured the Infrastructure Investment andJobs Act, and later included the Inflation
Reduction Act; and• Formation of Committees on Port Resilience,
Geothermal Energy, and Recycling of Clean
Energy Materials to explore how investments inrenewable microgrids, firm renewable energy,
and PV and battery energy storage system
recycling could improve island community
resilience and Hawaiʻi’s economy.
HEPF held the 2023 Legislative Briefing (“Briefing”)
on January 12 at the University of Hawaiʻi at Mānoa
campus. The Briefing’s theme “Strategic Alliances
for Decarbonization and Energy Self Sufficiency”.
focused on gaps in Hawaiʻi’s energy infrastructureand how the Infrastructure Investment and Jobs Act
and the Inflation Reduction Act could be used toaddress the most vulnerable aspects of that
infrastructure. This event also celebrated the HEPF’s
20th anniversary.
The U.S. Deputy Secretary of Energy David Turk
presented the Keynote Address – affirming thestrength of our historic partnership with the
Department of Energy and introducing a panel
discussion with the newly inaugurated Governor of
Hawaiʻi, Josh Green. This was followed by a full dayof panel discussions and briefings. The Briefing also
concluded Climate Week, a collaboration organized
by HEPF and the State of Hawaiʻi’s Climate Change
and Adaptation Commission. Following the final

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

24panel discussion, the participants proceeded to
Washington Place for a 20th anniversary reception
hosted by the Governor and First Lady. Video of theBriefing and its agenda can be found athttps://manoa.hawaii.edu/hepf/index.php/elementorhomepage/2023-legislative-briefing/.
In response to the critical needs addressed during theBriefing, HEPF created an online informational
resource for members and the public focusing oncompilation of the significant new federal policies
related to energy which includes a description of thepolicy, policy type, relevant sector, funding
opportunities, and managing agency. Initially, thisfeatured the Infrastructure Investment and Jobs Act,and later included the Inflation Reduction Act.
With the departure of a key member of HNEI’s
faculty who managed the HEPF activities through the2023 legislative briefing, the HEPF is again at adecision point. The HNEI is committed to the successof the HEPF and expects to expand support staff in
the near future.

Funding Source: Energy Systems Development
Special FundContact: Richard Rocheleau, rochelea@hawaii.edu;
Adam Strubeck, strubeck@hawaii.edu;
Mitch Ewan, ewan@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

25

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A6: Molokaʻi Community Energy Resilience Action Plan

OBJECTIVE AND SIGNIFICANCE: In 2022 and 2023,
stakeholders in Molokaʻi developed the Community
Energy Resilience Action Plan (CERAP). The
CERAP is a first of its kind initiative in Hawaiʻi andrepresents an independent, island-wide, communityled & expert-informed collaborative planning process
to increase renewable energy on Molokaʻi. HNEI
supported the CERAP process by providing technicalexpertise, data, modeling capabilities, and technicalreviews throughout the project.
KEY RESULTS: On July 7, 2023, Sustainable
Molokaʻi and the Molokaʻi Clean Energy Hui
submitted the first Molokaʻi Community Energy
Resilience Action Plan (Molokaʻi CERAP 1.0) to theCommission (Docket #2019-0178) in collaboration
with the Molokaʻi community and HNEI as the leadtechnical partner. This community-led, island-wideplan is a road map “to achieve 100% renewableenergy for Molokaʻi that is feasible, respectful of
Molokaʻi’s culture and environment, and strongly
supported by the community.”
BACKGROUND: For many years Molokaʻistakeholders and community members haveexpressed concerns over power system reliability,
affordability, equity, and engagement. A primaryconcern of the community is that their priorities andvalues were not reflected in the planning process
conducted in HECO and the Commission’s
conventional planning studies (PSIP and IGP).
As a result, several utility-scale renewable energy
projects were proposed and ultimately cancelled due
to community opposition. These projects included
large utility-scale wind projects and inter-island
cables connecting Molokaʻi to Maui and Oʻahu, aswell as smaller hybrid solar and storage projects.
When HECO last initiated a competitive procurement
for new renewable generation, Molokaʻi stakeholders
requested that the Commission pause any
procurement to allow for a community-basedplanning process to outline local priorities andobjectives to achieving a 100% clean electricity.
Since 2020, the Sustainable Molokaʻi and the Huiconducted a stakeholder-driven, community-led
planning process to solicit input on key priorities andobjectives. HNEI was selected to augment thiscommunity engagement with technical analysis.

Figure 1. Molokaʻi Clean Energy Roadmap.

PROJECT STATUS/RESULTS: Throughout the
CERAP 1.0 process, HNEI advised Molokaʻistakeholders on utility-planning processes, datacollection, and preliminary grid modeling. The HNEI
team developed a simplified power system dispatch
tool to select candidate resource portfolios andevaluate load, renewable generation, storagescheduling, curtailment, and oil consumption. The
tool was developed using Excel-based formulas anddashboards to allow easy use, dissemination, andtesting among Molokaʻi stakeholders.
The HNEI team also met with Sustainable Molokaʻi
on-island in January 2023 to review project status,
discuss opportunities to improve the analysis, and tobetter understand community objectives and powersystem infrastructure. After this meeting, the HNEI
team helped to identify potential tax credits available
in the Inflation Reduction Act, and helped scope out
potential future analysis necessary to continue the
CERAP planning process.
The final CERAP 1.0 report was filed with theCommission in July 2023. HNEI will continue to stayengaged in both the Commission’s regulatory review,
HECO’s standard planning processes (IGP), and the
Molokaʻi Community’s CERAP 2.0 analysis.
Funding Source: Energy Systems Development
Special Fund; Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

26

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A7: Energy Transition Initiative Partnership Program

OBJECTIVE AND SIGNIFICANCE: The Energy
Transition Initiative Partnership Program (ETIPP) isa program with an initial three-year term establishedand funded by the U.S. Department of Energy toprovide analysis, technical assistance, and policy
guidance to address high energy costs, reliability, andinadequate infrastructure challenges faced by island
and remote communities. In December 2020, HNEI
was selected via a competitive solicitation to be thePacific Regional Partner, one of five regional partners
initially selected nationwide, to help communities
coordinate with National Renewable Energy
Laboratory (NREL) personnel to; solve criticalquestions and issues of importance by communities
engaged in energy transitions, to support replicableenergy transition technical assistance and knowledge
sharing to inform, and to support energy transitions
throughout the United States.
BACKGROUND: ETIPP provides technical assistanceopportunities for remote, island, and islanded
communities. Through its understanding of local
energy and infrastructure challenges, goals, andopportunities, ETIPP's partner network is intended toempower communities to proactively identify andimplement strategic, holistic solutions tailored to theirneeds. Selected communities receive support for a
project scoping phase, approximately one to twomonths, followed by 12 to 18-month long energy
planning and analysis projects that: 1) prioritizecommunity energy values, goals, challenges, andopportunities; 2) identifies and advances the ability to
implement strategic, whole-systems solutions; and 3)
fosters high-impact, replicable community energy
transition approaches. By participating in ETIPP,
communities can expect to receive substantial in-kind
support from the national labs and regional partners
in the form of technical expertise on energy analysis,planning and implementation, and program guidanceand education from the regional partners.
PROJECT STATUS/RESULTS: During 2021-2022,
HNEI led efforts to seek qualified applicants fortechnical assistance and initial onboarding andorientation training session for representatives of fiveawarded Pacific Region Cohort 1 and 2 projects andparticipated in the delivery of training and technicalassistance.

In 2022, HNEI supported the successful conclusion of
the two Cohort 1 projects. The first, a Cohort 1 project
proposed by community partner, Hawaiian ElectricCompany (HECO), identified locations within its
distribution service territory in Honolulu deemedmost appropriate for hybrid microgrid development.
Such a map – perhaps the first in the United Statesdeveloped by a utility – is intended to improve
resilience of remote and low-lying electricity grids inthe face of severe weather conditions, which have thepotential to cause long-duration power outages. An
example of the hybrid microgrid map for the northeastO‘ahu community of Hau‘ula is shown in Figure 1.

Figure 1. Potential Hauʻula sites for hybrid microgrids.

The second Cohort 1 project completed during 2022
was the County of Kauaʻi’s “Electric Vehicle andMulti-Modal Transportation Transition” project,which supports the island’s effort to eliminate fossil
fuel use in the ground transportation sector by 2045.
The Kauaʻi program’s technical assistance focused on
three main tasks to support development of
convenient mobility options:
1. Develop a shared transportation mobility dataplan to collect information on movement
patterns of both residents and visitors and assess
detailed transportation demand around theIsland;Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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27

2. Analyze and plan the role of emerging mobility
technologies in conjunction with Kauaʻi’s
existing transit plans to support a broader arrayof transportation choices for visitors andresidents on the island; and3. Devise plans for electric vehicle charging
infrastructure to improve the mobility andaccessibility needs of residents and visitors on
the island and expand charging access for those
who are not willing, able, or prepared to shift
away from single occupancy vehicles at thistime.
Results of the projects from Cohort 1 have been
submitted to NREL.
In 2022, HNEI also supported the selection andscoping efforts for three projects under Cohort 2 in
the Pacific Region, which are as follows.
Hui o Hauʻula, Hawaiʻi (2022-2024):
Hui o Hauʻula, a community organization of O‘ahu,
is coordinating the planning and development of a
Community Resilience Hub, which will include thegeneration and storage of power for the surroundingKoʻolauloa District. HNEI is collaborating with
NREL on evaluating a portfolio of renewable energy
technologies for the Resilience Hub. The project willdevelop technical guidance and documentation forstorm and disaster energy resilience throughoutKoʻolauloa.
University of Hawaiʻi, Hawaiʻi (2022-2024):
The University of Hawaiʻi’s project plans include
analyzing the potential for geothermal cooling inbuildings across its 10 campuses. HNEI is supporting
NREL’s efforts to conduct analysis on building
heating and cooling loads at select locations andsupport NREL’s modeling of shallow geologic
conditions. The objective is to recommend
geothermal technologies, materials, and design
approaches that improve energy efficiency andsignificantly increase sustainability across campus
communities. Outcomes will include increased
capacity for geothermal energy analysis at the
University and opportunities to apply project resultsin similar environments.

Guam Power Authority, Guam (2022-2024):
The Guam Power Authority (GPA) is seeking
assistance on renewable energy resource integration,
improved utility planning and energy security, and toestablish a performance management system for its
Clean Energy Master Plan.
In 2023, Mark Glick, HNEI’s PI for the execution ofthis work took a leave-of-absence from HNEI to
become the state’s Chief Energy Officer. In order tocompensate for the loss of Mr. Glick, HNEI hired
Skog Rasmussen LLC to support HNEI’s community
efforts. Funds from the ESDSF were committed tothis effort to ensure that all program requirements
were met. During 2023, HNEI’s team participated in
the first Regional Partners meeting held in Denver,
Colorado and worked with local communities to
identify two additional applicants for Cohort 3.
Of the two Cohort 3 applicants – only one, theMolokaʻi Community Hui – was selected to move
forward. The Molokaʻi application includes the three
activities below, which are currently being developed
for potential inclusion in the Scope of Work for
Cohort 3.
1. Assessing the feasibility and cost-effectivenessof floating solar at the Kualapuʻu reservoir incentral Molokaʻi, for which there is strong
community interest.
2. Development of planning for renewable energy– a top community priority – for a range ofcritical infrastructure, county wide.
3. With a shared location at Kualapuʻu reservoir,
the community is interested in the feasibility ofpumped-storage to meet community needs.
Funding Source: U.S. Department of Energy;
Energy Systems Development Special FundContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

28

Hawaiʻi Natural Energy Institute Research Highlights
Appendix A: Hawaiʻi Energy Analysis – Community Support
A8: Hawaiʻi State Energy Office Support

OBJECTIVE AND SIGNIFICANCE: Following
extensive discussions with the Hawaiʻi State Energy
Office (HSEO), HNEI and HSEO identified several
potential project areas in critical need of additional
resources for continued progress for Hawaiʻi’s energy
transition. An agreement was reached for HNEI to
support the HSEO to conduct work in various areas
with the objective to address critical energy transitionneeds.
BACKGROUND: In February 2019, the Research
Corporation of the University of Hawaiʻi, on behalf
the University of Hawaiʻi’s HNEI entered into anagreement with the State of Hawai‘i, Department of
Business, Economic Development, and Tourism,
State Energy Office to conduct work and acceleratestate progress in the areas of Energy Efficiency,
Renewable Energy Generation Diversification andSupport, Grid Opportunity Assessment, and Clean
Transportation. In July 2021, following a period oflimited activity the agreement with DBEDT was
modified to include the following activities:
Task 1: Renewable Energy (RE) Generation
Diversification and Support to support professional
and technical services, subject matter expertise,analysis, and/or support in the development anddiversification of renewable energy generation
toward meeting state energy policies and goals. The
objective of this Task is to provide information andcoordination assistance to facilitate permitting andinterconnection of renewable energy projects to
support project siting and reduce project conflicts
and delays. This task explicitly included support for
the Powering Past Coal task force in support of Act
23, Session Laws of Hawaiʻi 2020, and statewide
coordination tasks assigned to the Hawai‘i State
Energy Office by Act 122, Session Laws of Hawaiʻi
2019, and in Chapters 125, 141, and 196 of the
Hawai‘i Revised Statutes.
Task 2: Grid Opportunity Assessment to support
development of models for energy anddecarbonization policy considerations for alternative
pathways to achieve a particular end-state. HSEO
proposed that a University of Hawaiʻi at Mānoa’s
Data Science Institute Fellow (“Fellow”) will create
and run modeling scenarios, generate datasets, andcommunicate the results with data visualizations toprovide insights on the relative benefits and impacts

to the electric sector of achieving state policy throughdifferent strategies, such as straight fuel switching(gasoline to electric) versus a combination of fuelswitching (gasoline to electric) and transportation
efficiencies.
Task 3: Clean Transportation Transition Support isintended to support professional and technicalservices, subject matter expertise, analysis, and/or
support to promote an accelerated transition to clean
groundtransportation
andadvancestatetransportation energy policies and goal. The objectiveof this task is to automate the collection andpreparation of data sets, load the data into a databaseaccessible to both internal and external stakeholders
to the extent possible, perform analyses, and develop
data visualizations to address policy and technology
questions relevant to Hawaiʻi’s transition to a net
negative carbon economy by 2045.
PROJECT STATUS/RESULTS: HSEO has reported
substantial progress in each of the three tasks.
Highlights of those accomplishments by task aresummarized below.
Task 1 RE Generation Diversification and Support:a) HSEO staff supported of the Powering Past Coal
Task Force, conducting approximately monthly
meetings and development of a Master
Schedule. Separately, HNEI developed an easy
to use tool to assess monthly Oʻahu gridreliability for different build-out scenarios for
the Stage 1 and Stage 2 solar plus storage plants.
b) HSEO staff participated in and provided input
to a coordination effort convened by the Countyof Maui in response to a Public Utilities
Commission and Maui Electric Company
letter. The Maui-focused group, the Maui
County Accelerating Clean Energy and
Decarbonization Implementation Technical(ACED-IT) Working Group, was intended toemulate the success of O‘ahu’s Powering Past
Coal Task Force. As stated in the letter, “one of
the lessons from retiring the AES coal plant onOʻahu is that cooperation with local
government and community engagement
improves the likelihood of success for the entire
set of needed actions. Based on our successful
experience with Governor Ige’s Powering Past
Coal Task Force on Oʻahu, we are requesting

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

29an opportunity for similar collaboration withyour Administration.”c) Important data, geospatial analysis, and generalproject
development
andpermitting
information have been provided to support theappropriate and effective siting of future
renewable energy projects. Examples include
maps used in presentations and on the HSEO
website, input on land use ordinance revisions,estimates of greenhouse gas emissions,continued work on property tax issues,
community outreach, and formal comments tothe utility and Public Utilities Commission
regarding the Stage 3 request for proposals
seeking firm and renewable generation onO‘ahu, Maui, and Hawai‘i Island.

updated version of the HAVEN web application,
an immersive data visualization tool tailor madeto facilitate comparative analytics of capacity
expansion and production cost scenario outputs.
The decarbonization of transportation scenarios
are expected to be prominent components of
HSEO’s Act 238 Decarbonization Pathways
report.
Funding Source: Energy Systems Development
Special Fund; U.S. Department of Energy
Contact: Richard Rocheleau, rocheleau@hawaii.edu
Last Updated: November 2023

Task 2 Grid Opportunity Assessment:a) The Fellow incorporated technology andresource inputs and specifications from
Hawaiian Electric’s
IGP Inputs
andAssumptions workbooks into the Oʻahu and
Hawaiʻi Island open source Engage model
developed by NREL. Baseline runs to test themodel’s stability and ability to run scenarios thatincorporate generic capacity expansion andexisting generation resources have been
performed.
b) The Fellow supported development of written
documentation detailing the source of all inputs,
constraints, technology configurations, resource
profiles that are in the current working HSEO’s
Oʻahu and Hawaiʻi Island Engage model.
c) The Fellow has also provided support on theMaui, Molokaʻi, and Lānaʻi Engage models andthe development of a data pipeline that will
enable the outputs from capacity expansion anddecarbonization scenarios that are run within
engage to be loaded into the HAVEN web
application for comparative analytics andimmersive visualization.
Task 3 Clean Transportation Transition Support:a) The Fellow contributed to the development of an
updated version of the HAVEN web application,
immersive data visualization tool tailor made tofacilitate comparative analytics of capacity
expansion and production cost scenario outputs.
The Fellow completed a beta version of an
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

30

Hawaiʻi Natural Energy Institute Research Highlights
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
B1: Oʻahu Near-Term Grid Reliability with AES Retirement

OBJECTIVE AND SIGNIFICANCE: The AES Hawaiʻi
coal plant, the largest power plant on Oʻahu retired on
September 1, 2022. This retirement decreased theamount of dispatchable fossil capacity available to theutility by more than 10% and was the largest single
source of electricity on Oʻahu. From 2021 to 2023,
the HNEI-Telos Energy team routinely conductedreliability analysis of the retirement to brief HECO,
Hawaiʻi Public Utilities Commission (PUC), and theGovernor’s Power Past Coal Task Force on theimpacts of project delays, cancellations, and otherevents. The objective of this ongoing study is toevaluate the ability of proposed solar + storage
resources to provide the required energy needed,while also maintaining grid reliability amid
generation shifts. The results of this work are
expected to have important implications for powersystem planning and policy for Oʻahu.
KEY RESULTS: Stochastic analysis, using the tools
previously developed by the HNEI-Telos Energy
team and reported last year, are being used to assess
capacity reliability risks associated with the AES
retirement, updates for utility plans, and possible
impacts due to delays in project schedules, and new
trends in HECO’s generator outage rates (-), therecent failure of Kahe 4 (-), project delays (-), andload (+). Analysis shows that with the retirement of
AES in September 2022, with only one replacement
resource available (Mililani I, 39 MW) and later(Waiawa I, 36 MW) in 2023, Oʻahu is currently in a
supply deficit until other Stage 1 and 2 solar + storage
resources become available.
However, as of September 2023, recent trends in theOʻahu peak load, which are still approximately 100
MW lower than pre-pandemic levels, mitigate muchof the reliability risk through the end of 2023 and startof 2024.
With ever-changing delivery schedules due to both
local issues, such as interconnection requirement
studies, permitting, and global shipping delays, thiswork is ongoing and will continue until sufficient
resources are deployed to ensure capacity needs are
met.
BACKGROUND: As the Hawaiʻi grid transitions torenewables including higher percentages of variable
renewable energy, these new resources are required

to provide not only energy, but also to provide
capacity and other grid services currently provided byfossil generation. Current utility plans call for
combining solar with battery storage resources
allowing solar energy to be shifted from the middle ofthe day, when there is surplus renewable generation,
to other times of the day including the evening peakload hours that occur after the sun has set. The
inclusion of storage into these systems offers theopportunity for them to provide grid services, one ofwhich is capacity – or the ability to provide energy
when it is required for reliability. The first test of thisstrategy occurred with the retirement of the AES coalplant in September 2022.
SB 2629 enacted in 2020 bans coal-fired generationin Hawaiʻi after 2022, ensuring the AES retirement.
The initial objective of this study, requested by the
PUC, was to evaluate the ability of the planned Stage
1 and Stage 2 utility scale solar + storage plants toprovide the capacity resources needed to ensure
reliable grid operations now that the AES coal plantis retired.
The Stage 1 and 2 solar + storage projects wereoriginally proposed to be completed in 2022, prior to
or concurrent with the AES retirement. However, as
of November 2021, several of these projects areencountering delays, pushing their delivery dates tobeyond the legislatively mandated AES coal facility
retirement. As of October 2023, only two of theremaining seven projects are online and operating,with the remaining projects not expected until 2024.
As a result, the power system is currently in a supply
deficit.
Since the completion of the 2021 analysis, numerous
events and trends occurred on Oʻahu that required a
reevaluation of Oʻahu’s reliability:
1. Continued project delays across most of theStage 1 and Stage 2 projects continue to be a risk
to Oʻahu grid reliability. The primary AES
capacity replacement (185 MW standalone KES
BESS) originally delayed until May 2023,
experienced a failure during commissioning andtesting – pushing back the projected online dateuntil the end of 2023 at the earliest.
2. The Kahe 4 (90 MW) oil generator was removed
from service due to equipment failure in July
2022. This plant was expected to be back online

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31

by Spring 2023, but as of October 2023, it
remains offline.
3. There was a notable increase in HECO’s forced
outage rates during 2020 and 2021 due to both
aging of existing thermal units and modificationof operations during COVID.
4. While project delays have exacerbated risk to
the Oʻahu grid, peak load dropped noticeably
during the pandemic and has not yet recovered.
It remains below the forecasted level, mitigatingsome of the reliability risk.
Given these changes, the PUC requested a refresh of
the 2021 reliability analysis to evaluate system
reliability through the end of 2022 and 2023.
Novel stochastic modeling methodologies –developed by HNEI and Telos Energy andsummarized in HNEI’s 2021 report to the legislature– that accurately account for the chronologicaloperations of storage, solar variability, and generator
outages are being utilized to determine if the proposed
solar + storage systems can maintain reliability in the
coming year. These models are being used to identify
key timelines as well as to assess the viability of othermitigating measures such as DER and the proposed
rescheduling of HECO generator maintenance. The
methodology developed by HNEI and Telos Energy
is now also being deployed in HECO’s Integrated
Grid Planning (IGP) process.

PROJECT STATUS/RESULTS: The stochastic
methodology is being used to evaluate the reliability
the Oʻahu grid, following the AES coal plant
retirement assuming different buildouts of utilityscale solar + storage resources. Each case is analyzed
across 1,008 random draws (replications) of
chronological dispatch, representing 21 years of solar
data and 48 unique outage draws for each year of solar
data. The output of each analysis includes the number(probability), the magnitude, and the duration of
capacity shortfall events that might occur when there
are not enough available resources to serve load. An
example of this process is provided in Figure 1.
This methodology was repeated across 27 cases,
which evaluated a range of three solar + storagelevels, three peak load levels, and three forced outage
rates.
1. Solar + storage of 39 MW (Mililani),
89 MW (+Waiawa & West Oʻahu),
and 139 MW (+HoʻOhana)
2. Peak load values of 1085 (2022 data), 1150
(IGP), and 1215 MW (2017-2019 data)
3. Forced outage rates of 7.5 (2015-2019), 11(midrange), and 15% (2020, 2021)
Each of these cases was evaluated with and without
the Kapolei Energy Storage (KES) battery energy
storage system for a total of 54 scenarios.

Figure 1. Example of Loss of Load Hours by solar years and outage draw.
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32Unlike the results provided in 2021, which werepredicated on a single estimate of forced outage rates,
system load, and replacement schedules, this analysis
was reported in a manner that allowed a user to selectany level of solar, forced outage, and load plus KES
operability for any given month to calculate key
resource adequacy metrics (LOLE, LOLH, EUE,etc.). The resulting customizable tool was provided to
key stakeholders participating in the Governor’s
Powering Past Coal Task Force to allow for ongoingevaluation of results as new data arises and timelinesof resource construction projects change.
Results of the 54 evaluated cases are provided in thematrix in Figure 2, which shows the loss of load
expectation – measured in average days of capacity
shortfall in a year – across a range of solar + storage
replacement, load levels, forced outage rates, andwith and without the KES battery. Higher numbers,
highlighted in yellow and orange, represent
conditions with high risk.

One example of the results converted into a monthly
forecast is provided in Figure 3. This was developed
assuming the current schedule of replacement
resources, including the cancellation of KES, andload remaining below pre-pandemic levels
throughout 2023.

Figure 3. Expected monthly loss of load expectation
based on current proposed schedules and returning load.

The KES resource is a critical component of Oʻahu’s
reliability plans, at least until the remaining Stage 1
and Stage 2 solar and storage projects come online. If
continued delays occur and load growth returns to
pre-pandemic norms, then the reliability of the Oʻahu
system could be jeopardized. Currently load levels
remain low and Oʻahu is now exiting the seasonal
peak demand period, suggesting that reliability risk
will remain low until next Spring at which point KES
is expected to be operational.
Funding Source: Office of Naval Research; Energy
Systems Development Special FundContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Figure 2. LOLE (days per year) for 2023 evaluated across
54 scenarios.

In the summer of 2023, replacement resources
experienced another setback when the KES (185MW) battery energy storage system had an equipment
failure during commissioning and testing. Current
information about the failure is sparse and treated asconfidential, but the expected commercial online date
for the plant is deferred another four to five months
until late December 2023.
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33

Hawaiʻi Natural Energy Institute Research Highlights
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
B2: Maui Near-Term Reliability and Kahului Retirement Analysis

OBJECTIVE AND SIGNIFICANCE: The Kahului Power
Plant (KPP) was once scheduled to retire by the endof 2024, but delays in procurement and constructionof replacement resources have pushed that date backto 2027. In addition, the Māʻalaea M10-M13 diesel
generators have been identified for retirement in 2027
due to lack of replacement parts. Both units will need
to be retired due to emissions compliance and air
permitting regulations. The objective of this study
was to update the 2021 and 2022 analysis andreevaluate Maui reliability if one or both of the plants
are retired and evaluate potential mitigations
necessary to preserve system reliability. The resultsof this analysis were briefed in 2022 to the Hawaiʻi
Public Utility Commission (PUC) and the Maui
Accelerating Clean Energy & Decarbonization
Technical Working Group (ACET) and are expected
to have important implications for power system
planning and policy for Maui.
KEY RESULTS: Stochastic analysis, using the tools
developed by the HNEI-Telos Energy team, wasconducted. It was found that either the KPP or M1013 retirements without deployment of othergeneration sources would significantly reduce system
resource adequacy as measured by loss of load
expectation (LOLE). However, the analysis showedthat partial deployment of proposed hybrid solar +storage projects would improve system reliability
compared to current reliability levels, but that
additional resources beyond the 80 MW currently
under construction will be necessary to meet
reliability requirements if both plants are retired.
The number and size of proposed replacement
projects, the retirement timeline, and the ability toextend KPP and/or M10-M13 operation, if necessary,
makes the reliability risk on Maui less acute than thesituation on Oʻahu, but time is running out for new
replacement resources to be available in time.
BACKGROUND: KPP is a 36 MW steam oil power
plant located in Kahului, Maui. It is comprised of four
separate steam oil generators and is over 72 years old.
Maui Electric Company (MECO) has frequently
proposed retirement of the plant over the past decade,but had not been able to develop and procure

replacement resources due to project delays andregulatory limitations. Currently, there is a proposedtransition plan by the utility comprising deploymentof utility scale solar + storage hybrid resources andupgrades to the transmission system. According to
Hawaiian Electric (HECO):“The KPP Transition Plan has several key components:(1) the Stage 1 and Stage 2 RFP projects will provide
capacity and energy replacement and grid services; (2)the K3 and K4 generating units of KPP will be converted
and repurposed to synchronous condensers to replace
critical voltage support service and synchronous
inertial response provided by KPP, among otheressential grid services; (3) the Waena Switchyard
project will maintain functionality and reliability of thetransmission system serving Maui in the absence of
KPP, avoid circuit overloads, and reliably integrate
new renewable resources; and (4) contingency plansthat include DER grid service programs and a review ofgenerator maintenance schedules as needed.” 1
The retirement of KPP has been planned for several
years and in 2021 HNEI conducted a detailed
evaluation of its replacement with the proposed Stage
1 and Stage 2 solar + storage projects. These projects
included 135 MW of solar with 540 MWh of storage,
along with a 40 MW, 160 MWh standalone battery in
Waena. Projects were originally anticipated to comeonline between 2022 and 2023, but project delays andsupply-chain constraints have occurred – cancellingsome projects and pushing online dates back to 2024
or potentially 2025. Additional projects being
proposed face growing community opposition andincreased project costs. The Lahaina wildfire andreconstruction efforts may also further challenge new
replacement resources.
In addition, since the reliability analysis conducted in
2021, HECO was notified replacement parts may nolonger be available for the M10-M13 diesel units.
According to the manufacturer, “the engines have
manufactured for more than about 40 years ago, someengine-related parts might no longer be available forsupply due to the business closing at our suppliers andif there is no alternative way to produce parts
anymore. So in that case we will officially inform youthat the parts cannot be supplied as an response to
your each RFQ.” 2

1 HECO Kahului Power Plant Transition Plan, April 5, 2021, Docket No. 2021-0024.
2 HECO letter to the PUC, March 21, 2022, Docket No. 2021-0024.

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34

HECO notified the PUC that they only have parts on
hand to service the units through the first half of 2024.
After that date, HECO anticipated a potential end oflife around 2025-2026. Given the project delays anduncertainty in the Stage 1 and 2 solar + storage
projects and the uncertainty in the future of KPP and
M10-13 generating units, HNEI was asked by theCommission to reevaluate grid reliability on Maui in
2022.
HECO’s final Integrated Grid Planning (IGP) Inputs
and Assumptions were finalized after the 2022
analysis was completed. As such, HNEI completed areevaluation of the retirement plans with new load
growth forecasts as an input into the efforts to assessload flexibility on Maui. This 2023 analysis waslargely consistent with earlier analyses and identified
portfolios of resources capable of replacing the aging
fossil fuel generators.
Since this analysis was completed, wildfires on Mauihave devastated the community and focused attention
on the utility’s plans for the future.
PROJECT STATUS/RESULTS: To assess the reliability(specifically resource adequacy) of the Maui systemwith the KPP and M10-13 retirement and replacement
solely with variable renewable energy and energy
storage, HNEI and Telos Energy conduced a resource
adequacy analysis. This process was utilized by
HNEI throughout 2021-2023 and recently adopted by
HECO. It utilizes sequential Monte Carloprobabilistic modeling which incorporate 22 years ofchronological solar data, 8 years of chronologicalwind data, and hundreds of samples of thermal
generator outages. This is the same probabilistic
methodology used to evaluate the AES coal plant
retirement on Oʻahu.
Grid simulations were conducted across seven
scenarios with assumptions on load, DER integration,and other system details derived from HECO’s IGP
assumptions for the year 2026. The Reference Point
scenario assumed the current grid’s resource mix,
including KPP and M10-13, without additional
retirements or new solar resources. Three additional
scenarios were evaluated; 1) with KPP retired, 2) with
M10-13 retired, and 3) with both KPP and M10-13
retired. This evaluated retirement levels between 33
MW and 82 MW.
This analysis was similar in nature to the work
conducted in 2021 and 2022, but was updated in 2023
to reflect recent cancellations and delays in Stage 1
and Stage 2 replacement resources as well as recentchanges to the Maui load forecast.
Each of these scenarios was evaluated without any
replacement resources, and across a range of solar +storage replacements from 20 MW to 180 MW, using
equal 20 MW tranches of new resources. In addition,
the matrix of cases was conducted with and without
the 40 MW Waena standalone battery system, which
has not yet received Commission approval. A chart ofthe installed capacity evaluated in the Reference
Scenario, the retirement scenarios, and thereplacement scenarios is provided in Figure 1.

Figure 1. Loss of Load Expectation with oil retirements and solar + storage replacement.
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35Each case was analyzed across 506 random samples(replications) of chronological dispatch, representing
22 years of weather data (23 solar, 8 wind) and 22
outage profiles per weather year (506 total). The
output of the analysis included the number, themagnitude, and the duration of the capacity shortfall
events that occur when there are not enough available
resources to serve load.
Results of the analysis are provided in Figure 2 withwhich shows the total amount of capacity retirements(MW) on the x-axis, and the loss of load expectation(LOLE, days per year) on the y-axis (note log axis).
Loss of load expectation measures the number of daysin the year where the Maui power system would haveinsufficient resources to meet demand, thus requiring
emergency measures or rolling blackouts. Each dot
measures the overall system reliability under a given
assumption of thermal retirement (K1-4, M10-13)
and solar + storage replacement. Contour lines areprovided to allow interpolation across a range ofretirement and replacement options.
This probabilistic approach – evaluated across a rangeof both retirement and replacement resource options– clearly shows the relationship between retirement
and required replacement resources to allow for easyinterpretation as timelines shift.
These results indicate that with the K1-4 retirement inisolation (-33.5 MW), any combination of 40 MW ofsolar + storage or standalone storage resources brings
the system back to its current level of reliability (i.e.
a near 1-1 replacement of oil with solar + storage).
The retirement of M10-13 in isolation (-50 MW),
would require more replacement resources, between
40 and 60 MW – again a near 1-1 replacement. With
both oil plants retired (-81.8 MW), between 80 and
100 MW of replacement solar + storage capacity
would be required to maintain reliability. Thishighlights that full deployment of the underconstruction hybrid solar + storage resources plus
additional resources would be required to meetcurrent system reliability levels.

Figure 2. Reliability Frontier for retirement of oil units
and additions of new resources.

There are options available to get to a reliable systemwith both units retired, including simply constructing
more hybrid units, which are currently being tenderedin HECO’s Stage 3 procurement process, building the
proposed 40MW Waena BESS (which was selectedin the Stage 1 solicitation but does not yet haveregulatory approval), adding load shifting or
customer-sited resources (such as the Grid Services
RFP), or other sources of generation.
In 2022 and early 2023, these results were shared with
the PUC, HECO, and the Maui ACET to support
ongoing planning in the state and continued
monitoring of Stage 1 & 2 replacement schedules.
The HNEI-Telos team plans to continue updating andrefining the analysis given changes to procurement
schedules, changes to load, and other systemdevelopments. Results of this work will be presented
to key stakeholders when it is relevant to do so.
Funding Source: Office of Naval Research; Energy
Systems Development Special FundContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Another way to visualize the data, shown in the
Figure 2, isolates the reliable scenarios for
replacement. This visualization makes the gap more
apparent between the resources currently underconstruction and the resources needed to retire bothunits.
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Hawaiʻi Natural Energy Institute Research Highlights
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
B3: Oʻahu Retirement StudyOBJECTIVE AND SIGNIFICANCE: Oʻahu’s fleet ofoil-fired generators is aging, becoming increasingly
unreliable, and more difficult to maintain. Increased
cycling to integrate variable renewable energy andmore stringent EPA emissions policies are also
decreasing the longevity of these units. In September
2022, HECO retired its largest coal-fired power plant
and replaced it with a portfolio of hybrid solar +storage projects. At that time, the HNEI-Telos teamconducted analyses showing that solar + storage
could reliably replace the coal plant. However, theability of solar + storage to continue replacing firm
capacity – resources that are available irrespective ofweather – diminishes at higher levels of retirements.
Given that significant amounts of firm capacity will
be required to operate a reliable grid (Appendix C1),HNEI-Telos conducted longer-term analysis to help
develop long-term retirement plans for Oʻahu.
KEY RESULTS: Under current load levels, the Waiau
steam oil plant (370 MW) could be retired reliably,
but would require 900 MW of solar and storage
hybrid resources – double the amount of recent
procurements. If load growth materializes as expected– largely from expected EV adoption – the sameamount of solar and storage could only retire 150
MW, a small portion of the total plant. As a result, toachieve state-wide decarbonization targets, the utility
needs to simultaneously plan for oil plant
replacements and the growing capacity needs tosupport electric vehicles.
While some of the oil units can be replaced by nearterm solar and storage additions, the ability tocontinue replacing fossil-fuel resources exclusively
with hybrid solar and battery plants is limited. Other
firm resources need to be considered for futureplanning.
BACKGROUND: HECO’s oil generation plants are
aging and becoming less reliable. On average, they
are over 40 years old, with some plants over 60 years
old – well beyond their original design life. The
Waiau power plant, for example, is the third oldest
non-hydro generating station over 20 MW in the
United States. These old systems lack the flexibility
required to integrate renewable energy sources
effectively, leading to increased curtailment andincreased likelihood of equipment failures.

Increased age, cycling, and emissions compliancerequirements are all eroding generator reliability andavailability. This trend, which started in 2015,
increased further in from 2020-2022.

Figure 1. Increasing maintenance and forced outages for
HECO’s Oʻahu thermal fleet.

Some of these plants will need to be retired, but it willtake years to plan, receive regulatory approval,
permit, interconnect, and construct new facilities.
Early and proactive planning, starting now, isessential to maintaining reliability and options in the
future.
PROJECT STATUS/RESULTS: Solar and storage caneffectively reduce the generation from oil plants,
allowing them to run less and reduce emissions
significantly. However, there are limits to how muchcapacity can be retired completely, while maintaining
a reliable system.
To assess the retirement and replacement options
available, HNEI conducted a study for Oʻahu that
evaluated system reliability across hundreds of
unexpected generator outages and over twenty years
of weather conditions. The system was evaluatedacross a range of load growth, solar and storage
additions, and additions of new firm capacity. The
scenarios evaluated included a combination of thefollowing parameters:• Load Growth: Evaluated Base Load and High
Load growth assumptions, representing acurrent load level and one based on a 2030-2040

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37

load level (with the range representing the paceof electrification).
• Solar PV and storage adoption: Various solar
and storage levels were evaluated, ranging fromsolar and storage levels procured in Stage 1 and
2 to an increase of 1100 MW of new projects.
• Firm Capacity Additions: The analysis was
conducted with and without the proposed 400
MW of firm capacity additions identified in the
IGP and Stage 3 Firm Renewable procurement.
Results show that recent procurements for solar andstorage present further opportunities for retiring
additional oil plants. However, solar and storage
resources alone cannot entirely replace all of the oilplants on the system. During extended periods of low
wind and solar availability, which can persist forseveral days, some dispatchable firm capacity is stillrequired to maintain reliability. Moreover, theincreasing adoption of electric vehicles contributes toa rise in overall load, which limits the possibilities for
retiring oil plants without new dispatchable firm
capacity.

Figure 2. Solar + storage additions required and oilretirements feasible while maintaining 0.1 days/year
LOLE reliability levels.

Under current load levels, the Waiau steam oil plant(370 MW) could be retired reliably, but would require
900 MW of solar and storage hybrid resources –double the amount of recent procurements. If load
growth materializes as expected – largely fromexpected EV adoption – the same amount of solar andstorage could only retire 150 MW, a small portion of
the total plant. As a result, to achieve state-wide
decarbonization targets, the utility needs tosimultaneously plan for oil plant replacements and thegrowing capacity needs to support electric vehicles.
Beyond the Waiau plant, there are little to no options
available to retiring additional capacity (i.e. the Kahesteam oil plant), unless some other firm capacity isadded to the system. Adding 400 MW of new firm
capacity to the system, for example, would allow for
the retirement of up to 700 MW of oil capacity
depending on the amount of solar and storage added,
even with continued load growth.

Figure 3. Solar + storage and firm renewable additions
required and oil retirements feasible while maintaining
0.1 days/year LOLE reliability levels.

By creating a portfolio of solar, storage, and newclean firm capacity, much of the legacy steam oil fleet
on Oʻahu can be retired. Given the continued need forfirm capacity, the age of HECO’s generation fleet,and ambitious state policy related to electric vehicle
adoption and other electrification efforts, prudent
retirement planning is warranted. Monitoring load
growth trajectories, specifically related to EV
adoption is needed. In addition, any planning for new
firm capacity additions should start now, as new

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38

plants will take several years for design, permitting,procurement, and interconnection. In the meantime,
HECO has an opportunity to retire a few priority units
while working to bring additional supply resources
online.
Table 1. Solar + storage additions required to maintainreliability at various levels of oil-generator retirements.
Solar + Storage Additions Needed
Cumulative
Retirements

Base LoadHigh LoadHigh Load +400 MW Firm

Waiau 3-4 (100 MW)

100 MW

600 MW

0 MW

Waiau 5-6 (200 MW)

300 MW

1000 MW

0 MW

Waiau 7-8 (370 MW)

900 MW

N/A

0 MW

Kahe 1-2 (550 MW)

N/A

N/A

300 MW

Kahe 3-4 (700 MW)

N/A

N/A

440 MW

Funding Source: Energy Systems Development
Special Fund and Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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39

Hawaiʻi Natural Energy Institute Research Highlights
Appendix B: Hawaiʻi Energy Analysis – Grid Reliability
B4: Oʻahu and Maui Load Flexibility

OBJECTIVE AND SIGNIFICANCE: HECO’s latest
Integrated Grid Plan (IGP) relies heavily on
customer-sited resources as part of the resource mix
to achieve the RPS. These customer resources include
significant levels of energy efficiency and rooftop
solar, and increasing levels of distributed batteries,and electric vehicles. Historically, these DER
resources were unobservable and uncontrollable, but
new technologies and grid service programs at theutility may allow for increased customers
responsiveness that can help to balance the grid, defer
new capacity, and help integrate additional solar PV.
The objective of this study is to quantify potential grid
benefits of load flexibility and identify characteristics
that are most valuable to the future grid.
KEY RESULTS: Analysis conducted by the HNEITelos team shows that a static daily load shifting fromevening peak to mid-day, such as might beencouraged by time of use (TOU) rate, would provide
limited bulk-system benefits on Oʻahu. This isbecause the amount of battery storage expected to be
deployed over the next few years saturates theopportunity of reducing peak load and moving load tothe middle of the day.
On Maui, there is a near-term capacity need andcurrent battery proposals (Waena 40 MW BESS) aresmaller than Oʻahu as a percentage of load. As aresult, while load flexibility will compete with future
battery storage, there is a near-term opportunity forload shifting to help maintain reliability when oil
capacity is retired in 2028.
Across islands, dynamic load flexibility – that moves
load throughout the day based on the day’s conditions
or across the week – is shown by HNEI/Telos analysis
to be considerably more helpful than static load
shifting for reliability purposes. This flexibility,
however, would require more sophisticated controls
or communication in place of, or in addition to, thecurrent proposed TOU rate.
BACKGROUND: With advances in DER technologies
and the proliferation of smart devices, customer load
can adjust to better align with the capabilities of thepower system. However, this load flexibility can only
be leveraged if appropriate programs and rates are
established to incent the behavior. The PUC andHECO are currently evaluating options for load

flexibility across a variety of initiatives, including
through advanced rate design (TOU rates), DER
Phase 3 program design, and a competitive
solicitation of grid services (i.e. Maui Grid Services
RFP). While each of these programs contributes toload flexibility, each will have different impacts on
the power system given the parameters and operating
characteristics of the program.
In parallel, HECO is planning to retire aging oil
generators and replace them with a mix of renewableenergy and battery energy storage. Over the next few
years, Oʻahu will be bringing online 400 MW ofhybrid solar + storage plants and 185 MW ofstandalone storage through the Stage 1 and 2
procurements and has plans to retire 371 MW ofgeneration at the Waiau power plant by 2030 (inaddition to the 185 MW AES coal retirement in2022).
On Maui, the Kahului K1-4 steam oil power plant isplanned to retire as soon as possible and the Māʻalaea
M10-M13 diesel generators may need to be retired
sooner than expected due to lack of replacement parts.
At the same time, hybrid solar + storage replacement
resources have been delayed or cancelled due tosupply chain disruptions, community opposition, andincreased project costs. These challenges have led tothe consideration of load flexibility as a capacity
resource to replace the aging generation.
PROJECT STATUS/RESULTS: The HNEI-Telos teamanalyzed the benefits of load on Oʻahu and Maui. The
study considered potential fuel cost savings andavoided capacity needs attributed to shifting up to
20% of evening residential load from the evening
peak load period to the middle of the day. This
analysis was conducted across multiple scenarios,
first evaluating grid operations prior to storage
additions, a near-term grid with planned solar andstorage additions, and a higher solar and storage
portfolio. This provides a view of changing systembenefits of load flexibility relative to the amount ofstorage on the grid.
Oʻahu Results
In the case of fuel cost savings on Oʻahu, TOU rates
have minimal benefits. The reason for this is two-fold.
First, while solar generation is abundant in the middleof the day, there is limited curtailment – even before

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40battery storage is added – and oil generation is stillneeded. Shifted load, therefore, is still served almost
exclusively by oil generation, albeit with a modest
improvement in plant efficiency (heat rate). Second,round-trip energy losses required to shift the energy(either via behind-the-meter batteries, pre-cooling ofevening air conditioning, or otherwise), leads to a netincrease in demand due to load shifting.
When batteries are added to the Oʻahu system, thesemodest benefits are reduced further as curtailment ofwind and solar is largely eliminated, and there arelimited fuel savings from additional load shifting.
However, TOU rates are designed, in large part, toreduce capacity needs rather than fuel savings. The
power system includes many “peaking” generatorsthat are built to run sparingly, only in times of highload and when needed for reliability. Load shifting, intheory, could reduce peak demand and avoid the needfor new “peakers” or enable oil plant retirements.
However, similar to fuel cost savings, the peakcapacity needs on Oʻahu are also being addressedwith battery storage additions.
To quantify the capacity impact, the study
implemented a sequential Monte Carlo probabilistic
model which incorporates 22 years of chronologicalsolar data, 8 years of chronological wind data, andhundreds of samples of thermal generator outages toquantify the resource adequacy of both Oʻahu andMaui. This process was used to test if the powersystem is reliable across a variety of conditions,
including unexpected generator failures or low windand solar conditions. The expected unserved energy(EUE) measures the likelihood of having insufficient
resources to serve load and the potential for rolling
blackouts.
The results show how TOU rates that discourage
energy use from 5pm - 9pm can effectively mitigate
reliability risk prior to battery storage additions(“Recent Past”), but would not meaningfully help
after grid-scale batteries are added (“Near Future”).
This is because the remaining reliability risk is spread
evenly across the day and the remaining capacity needis no longer isolated to evening peak demand hours.
In other words, there is less of a “peaking” need.

Figure 1. Distribution of EUE by time of day.

Maui Results
On Maui, where the near-term resource mix does not
yet include large amounts of energy storage, load
flexibility can be part of the mix to retire oil
generation, but competes directly with grid-scalebattery storage additions that are planned with theStage 1, Stage 2, and Stage 3 procurements.
Furthermore, the type of load flexibility could have asignificant impact on the reliability of the system.
Currently, there is approximately 80 MW of hybrid
solar + storage additions under construction on Maui.
These additions would be enough to retire K1-4 orM10-13, but not all 81 MW of generation across thetwo existing power plants. To address the gap inreliability from that remains from only adding 80
MW of hybrid resources, various types of load
flexibility were assessed for their resource adequacy
benefits, or loss of load expectation (LOLE). LOLE
assesses the resource adequacy of power systems
under various system conditions by using aprobabilistic resource adequacy methodology. This is
the same probabilistic methodology used to evaluate
the AES coal plant retirement on Oʻahu (Appendix
B1). The results of which are shown in Figure 3
across a range of potential mitigation options.
Several load flexibility options were considered, ageneral time of use rate “Static Load Shifting(TOU),” a dynamic, controllable DER program(“Grid Services RFP”), grid-scale standalone storage(“20 MW BESS”), and through “Daily Managed EV
Charging.” These options were differentiated in thefollowing way:
• The Grid Services RFP is modeled as a 20 MW
resource that can only contribute for 2

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41consecutive hours during specific times of theday. It also has 10% energy losses and must
charge during the daytime hours.
• The Static Load Shifting (TOU) is modeled as a
20 MW resource that moves roughly 75 MWhfrom the 5-9pm peak into the daytime andovernight hours.
• Battery energy storage is modeled as a 20 MW
resource that is fully controllable by the grid
operator, subject to energy limitations and roundtrip efficiency losses.
• Lastly, for reference a 20 MW perfect generator
was considered, with no energy limitations oroutage rates.

HNEI plans to continue to refine this analysis, withthe goal of supporting decision makers at the PUC
and HECO as they continue to design customer
programs to support evolving grid needs. HNEI hopes
to assess the value of load flexibility in deferring
distribution grid upgrades in a future version of thisanalysis.
Funding Source: Energy Systems Development
Special Fund; Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Results show that 20 MW of load flexibility iscomparable to the capacity grid services provided bya standalone storage resource, but that a hybrid
resource (which also brings additional energy) and aperfect capacity resource are more beneficial.
Another sensitivity was run that assessed load
flexibility throughout the week. This type of intraweek load flexibility was shown to improve LOLE by90+% depending on the scenario on both Oʻahu andMaui. Intra-Week load flexibility behaves like longduration storage in this regard.
The findings indicate that load flexibility can capturesome of the energy arbitrage value that batteries
provide, improving resource adequacy. Effectively,
the energy arbitrage benefit is quickly saturated bywhichever resource (Load Shifting or batteries)
arrives first.

Figure 2. Loss of load expectation (LOLE) in days per year with different load flexibility options.
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42

Hawaiʻi Natural Energy Institute Research Highlights
Appendix C: Future Energy Systems
C1: Clean Firm Needs

OBJECTIVE AND SIGNIFICANCE: This study was
intended to help inform and frame the ongoing
discussions and planning related to the need of
dispatchable firm capacity. The objective is to informfuture procurement and potential legislation for bothvariable and firm renewable energy. The analysis
sought to determine the minimum amount of firm
capacity that the system would require – at various
levels of wind, solar, and storage – to maintainadequate generation resources during periods ofextended poor weather. This analysis also evaluatedwhat levels of variable renewable energy can be
implemented without impacting (shutting the door)
on future options. This information can be used to
inform decisions on oil-fired power plant retirements,
guide procurement of new resources, and to quantify
challenges of relying solely on variable renewableenergy and storage alone for a 100% renewable grid.
KEY RESULTS: The findings of this analysis indicatethat on Oʻahu, even in a very high variable renewableenergy and storage grid, there is a need for verysignificant amounts of firm capacity, up to 600-750
MW. In this future clean energy system with very
high penetration of variable renewables, theseresources would only need to run sparingly, but are
essential for reliability. When they are necessary, it
could be for multiple consecutive days at a timemaking it difficult, if not impossible, to solve thereliability challenge by exclusively relying on
variable renewables and battery storage, even longterm storage. Today, this grid service is provided by
the existing HECO oil plants. These plants are aging
and becoming less reliable and cannot be converted
to meet the state’s 100% renewable energy target. At
some point, they will need to be retired and replacedwith other forms of firm renewable energy.
The analysis for Oʻahu was extended to each of theother islands to compare the total firm capacity needand operational characteristics of these resources.
Results for the state confirm that firm capacity needs
are approximately 50% of peak load for all theislands.
BACKGROUND: Despite the growth in wind, solar,
and battery technologies over the past ten years, there
is increased interest in firm renewable energy
technologies in Hawaiʻi and the power industry ingeneral. This is being driven by several factors,

including resource saturation, resource diversity,
reliability, and agricultural and forestry sector
objectives. Dispatchable firm capacity refers to power
generation that is available for a sustained period oftime, irrespective of weather conditions or theavailability of wind and solar resources.
In the 2022 legislative session, the Hawaiʻi State
Senate and House of Representatives introduced aseries of bills that sought to promote – and in somecases mandate – increased adoption of firm renewableenergy. For example, HB 1611 and SB 2510 proposed
to establish a state energy policy that requires at least
33.3% of renewable energy be generated by firm
renewable energy. These bills also proposed to limit
the percentage of any one type of renewable energy
source to 45% of all generation for each island, except
for geothermal generated energy. It was unclear if theintent of this requirement was to limit the percentage
of distributed PV and utility-scale PV to 45%, butsince some of the islands already have high levels ofthese resources, it could prevent the installation of
additional solar systems. These bills were approvedby both the Senate and the House, but later vetoed by
the governor. While these laws are not in statutetoday, there is continued interest in firm renewableenergy and likely will be the topic of future legislative
sessions.
In addition, on March 1, 2022, Hawaiian Electric(HECO) issued a request for proposals (RFP) seeking
proposals to acquire 500 to 700 megawatts of energy
from firm renewable generation resources on Oʻahu
with a targeted online date between 2029 and 2033.
According to HECO, “while solar and wind energy
resources will help us hit our near-term clean energy
milestones, we’ll also need firm renewable resources
available for customers when the sun isn’t shining, or
the wind isn’t blowing.”
The RFP also states that the objective of the firm
renewable procurement is to ensure that “sufficient
firm capacity must be available during periods of low
wind and solar production. Modernizing the ageing
fossil fuel generation fleet (some of which are over 75
years old) by adding new renewable firm generationis consistent with decarbonization goals and policies
as new firm generators will be installed alongsidesignificant quantities of low-cost renewables to

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43ensure reliability and resilience, resulting in overall
reductions in carbon emissions.”
There is also increased attention being afforded to therole of hydrogen in decarbonizing the Hawaiʻi energy
sector, including for electric power uses (Appendix
C2) along with locally sourced biomass and/or
biodiesel, and potentially the development of new
geothermal resources.
PROJECT STATUS/RESULTS: Given the recent
legislative actions and proposed firm renewableprocurements by the utility, HNEI conducted a seriesof analyses to identify the amount of firm renewablecapacity that may be required in Hawaiʻi. The
analysis was first conducted for Oʻahu and themethodology was later extended to the islands ofKauaʻi, Maui, Molokaʻi, Lānaʻi, and Hawaiʻi.

The scenarios and perfect capacity resources weremodeled across 21-years of weather resources (which
represented historical weather conditions from 19982018) for the solar and offshore wind resources. The
model was evaluated across all hours of the year in
the 21-year period, creating dispatch profiles fornearly 184,000 hours of chronological operations,
illustrated in Figure 2. The use of multiple years ofresource for this analysis, inherently considers theimpact of historic periods of low resource.

To quantify potential firm renewable needs, the study
team developed a simplified screening methodology
and then verified the results with robust probabilistic
resource adequacy and detailed operational modelingof a specific resource mix. The screening
methodology was conducted in a five-step process,illustrated in Figure 1.
The study team developed a small number of potential
future resource mixes that reach or exceed 90%
renewable energy, by varying the amount of solar +storage and offshore wind resources that are proposed
to be available. This step was done at increasinglevels of available wind and solar resources. UsingOʻahu as an example, resources were added in 1,000
GWh per year intervals. These scenarios were thenevaluated without the existing oil capacity on thesystem, to calculate the remaining amount of capacityand energy needed after accounting for solar, wind,and battery energy storage. These units were replacedwith blocks of perfectly available and flexible
capacity – which would operate in a manner to limit
total capacity additions while meeting the needs of thesystem.

Figure 2. Representative high and low solar weeks and theneed for firm renewables.

The results of the simulations were used to quantify
system performance and firm renewable capacity
needs. In particular, the metrics resulting from thisanalysis included the amount of curtailment ofvariable wind and solar resources, as well as theutilization of the perfect capacity resource. For theperfect capacity resource, particular attention wasgiven to the maximum dispatch of the unit, which
implies the overall capacity need. Operational metrics
like number of starts, ramp needs, operating hours,
and capacity factor by incremental block were also
evaluated. Cost metrics were also incorporated asproxy values for the perfect capacity resource – as if
it was provided by the existing oil-fired generating

Figure 1. Five-step screening methodology to calculate firm renewable needs.
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44

mix or a future firm renewable resource mix such as
biodiesel.
Results of the analysis are provided in Figure 3,
showing several islands firm capacity requirement asa percentage of peak load (y-axis) at varying levels of
solar and storage builds (x-axis). Only the maximum
dispatch of the perfect capacity resource is shown asa percent of system peak load – illustrating theaggregate capacity need of 40-50% of peak load –depending on the amount of variable renewableenergy and battery energy storage on the system.
These values can be used as a proxy for the firm
renewable resource needs of the system. This clearlyshows the relationship between increasing variable
renewables and storage capacity to the diminishingneeds for firm renewable capacity.

Figure 3. Firm capacity needs at increasing levels ofvariable renewable energy (PV+BESS) across islands.

However, the analysis also showed that even at very
high penetrations of variable renewable energy –reaching almost 95% of annual energy – there is stilla substantial need for firm capacity. This isapproximately 50% of the system’s peak demand andemphasizes the point discussed previously that there
are diminishing returns associated with additionalvariable renewable energy at high penetrations.
The analysis was repeated at various levels of electricvehicle penetration. The results for Oʻahu indicatethat a 20% increase in EV charging during peakdemand periods would only increase the firm

renewable requirement by approximately 50 MW,
and would increase by approximately 250 MW withthe 60% EV peak charging scenario. In addition, thesepeak demand needs were only modestly changed bydifferences if different charging profiles were
implemented. While daytime charging is slightly
better than peak demand or overnight charging
profiles, there is relatively little difference between
the time of charging and the additional firm
renewable capacity needed.
The reason for this is twofold; first, the system islargely energy constrained rather than capacity
constrained. As a result, the firm renewable needs arelargely driven by low wind and solar days rather thanhourly demand. Second, there is a significant amountof grid battery energy storage assumed in theseportfolios, and thus plenty of flexibility to moveenergy from one time of day to another. Overall,while EV adoption rates would change the total
amount of renewable energy needed to reach thestate’s renewable energy targets, the timing of EV
charging has a relatively modest impact on overall
firm renewable needs for reliability.
Today, there are limited zero emission resources
available to provide dispatchable firm capacity, andeach has limitations that must be considered. Biomass
and biodiesel, even if run sparingly, would requirelarge feedstocks exceeding available land use andrequiring imported fuels. Geothermal is available on
Hawaiʻi Island, but would likely require subsea,
interisland cables for Oʻahu and Maui. Hydrogen andother forms of multi-day storage could also provide
firm capacity, but would exacerbate land use
challenges, community acceptance, and costs remain
highly uncertain.
In addition, these options are all significantly more
expensive and more uncertain, than near-term
additions of solar, wind, and battery energy storage.
While these resources will not eliminate the need forfirm resources (currently provided by oil capacity),
they will diminish the need while increasing
renewable energy and CO2 emissions in the nearterm. These additions also do not close the door on
future options if new technologies or firm renewable
resources become available.

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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45This study is intended to be a screening analysis of
the potential firm renewable needs for the futureOʻahu system and to help inform proposed legislation
and utility procurements. In light of the Hawaiʻi State
Legislature’s efforts – through SB 2510 – to require aminimum amount of firm renewable energy, ongoingwork will be continued by HNEI to inform on theappropriate levels of firm renewables that may berequired. In addition, as the utility’s Stage 3 RFP and
Firm Renewable RFP continue to progress, additional
analysis can be conducted on specific portfolios andresource types.
Funding Source: Office of Naval Research; Energy
Systems Development Special FundContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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46

Hawaiʻi Natural Energy Institute Research Highlights
Appendix C: Future Energy Systems
C2: Hawaiʻi Hydrogen Integration StudyOBJECTIVE AND SIGNIFICANCE: Act 140 “Relating
to the Hawaiʻi Hydrogen Strategic Plan” of the 2022
Hawaiʻi State Legislature tasked HNEI to “examine
the potential for the production and use of renewablehydrogen in the State and the potential role ofrenewable hydrogen in achieving a local, affordable,
reliable, and decarbonized energy system andeconomy.” Results of this study are being finalized
and will be submitted to the legislature ahead of the2024 session.
In conducting this study, HNEI sought to identify andquantify the potential uses for hydrogen (H2) inHawaiʻi and to quantify the potential to producehydrogen locally to meet those potential uses. Basedon a conservative estimate for hydrogen use in
Hawaiʻi, the required materials, energy, water, land,
and infrastructure needed to serve that demand arequantified. These analysis are intended to determine
the feasibility of large-scale hydrogen production anduse across the state and whether Hawaiʻi can play therole of a hydrogen exporter.
KEY RESULTS: Results of this analysis show thatwhile there is a potential for hydrogen to reduce thecarbon intensity of some end uses, it is not likely tomake a significant contribution to Hawaiʻi’sdecarbonization efforts. With limited production
potential on Oʻahu relative to potential demand, thecost and difficulty of interisland transport ofhydrogen further limits its decarbonization potential.
Producing hydrogen using electrolysis is extremely
energy intensive. Given the ongoing challenges ofsiting new renewable resources to meet existing
electric power needs, the ability to develop sufficient
renewable energy sources solely for hydrogenproduction to offset meaningful quantities of oil
imports is likely infeasible with land use constraints
and community acceptance being significant factors.
Stated another way, while there is an opportunity forsome business development around the production
and use of hydrogen, it is unlikely to contribute to ameaningful reduction in our GHG emissions, outside
niche sectors.
BACKGROUND: During the 2022 legislative session,
multiple bills were proposed to encourage thedevelopment of an H2 industry in Hawaiʻi. HB 1611
proposed a State Energy Plan that specificallyaddressed firm renewable options, including H2,
across Hawaiʻi. HB 1937 requested that HNEI
develop a H2 strategic plan for Hawaiʻi, which
examined the State's ability to advance hydrogenproduction from local renewable energy resources.
The study shall consider hydrogen availability andfeasibility locally, water usage, costs/benefits,
identify end-use markets, permitting requirements,hydrogen for transportation and grid, technoeconomic feasibility, and environmental benefits forresiliency, and include a comparison to importedhydrogen.
The interest in Hawaiʻi for large-scale hydrogenproduction and use was further elevated by passage of
the Inflation Reduction Act and the expectation ofsignificant federal funding for a national network ofhydrogen hubs intended to decarbonize “hard toabate” sectors including chemical (ammonia, steel,cement), transportation (long-haul trucking), andpower (long-duration storage) sectors.
Beginning in 2022 and continuing through much of2023, multiple stakeholders in Hawaiʻi were actively
pursuing DOE funding for a local “hydrogen hub” inthe state. While Hawaiʻi’s Hub proposal identified
sufficient production potential to meet DOE proposal
requirements, to our knowledge, there has not been astudy to quantify and identify the means to produce
the quantities of hydrogen needed to decarbonize the
Hawaiʻi energy economy. Additionally, we are notaware of any assessment of integrating hydrogenproduction in a high variable renewable energy grid.
This study will serve as an initial basis for futurehydrogen analysis in Hawaiʻi as decarbonization
goals progress.
While many stakeholders have identified anddiscussed potential uses for green hydrogen, little has
been done to analyze: 1) the electricity required for its
production, 2) the storage that may be necessary for
implementation of a practical system, or 3) the fulllife-cycle cost associated with producing and usinghydrogen in Hawaiʻi. As part of this assessment underAct 140, the HNEI-Telos team conducted a detailed
analysis to identify high-priority use cases, quantify
the scale of potential hydrogen and electrolysis needs,
and to simulate the production and storage
requirements.

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47

PROJECT STATUS/RESULTS: A review of thepotential hydrogen demand by end use has been
completed and informs the basis of assessing how
Hawaiʻi can meet the expected demand via local
resources. The transportation and electric power
sectors make up the bulk of petroleum usage inHawaiʻi, offering potential markets for hydrogen, butcompetition from direct electrification must be
considered. Disaggregating the end-use sectors into
more granular energy uses, such as shown in Figure
1, is required to assess electrification versus H2
potential.

Figure 1. Example of the disaggregation of end use sector
energy input into electrification versus H2.

Based on an evaluation of potential end uses, the
HNEI-Telos team identified four uses as being themost technologically mature with the potential fornear-term deployment if clean hydrogen is available.
These are:
• Aviation: Production of sustainable aviation fuel(SAF) using hydrogen;• Medium/heavy duty vehicles: Buses and trucks,
primarily those that need longer range arepotential markets for hydrogen powered vehicles,
although this application could be challenged bycontinued advancements in battery technology;• Electric power: Hawaiʻi’s grids will need firm
dispatchable power and seasonal storage toensure grid reliability with high penetration ofvariable renewable generation; hydrogen for thisapplication may be challenged by developments
in long duration battery storage, biofuels, andadvanced geothermal; and• Oil refining/chemical processes: Residual
petroleum processing and industrial producers,
such as Hawaiʻi Gas, may have increased futurehydrogen demand.

Based on this assessment, the end uses most likely toincorporate hydrogen were quantified using existingplans or by assuming a meaningful penetration ofhydrogen use. Electric power needs were based on
meeting the firm fuel needs for 2045 shown in
HECO’s IGP plan, which is approximately 5% ofelectric energy. This assessment provides ameaningful scale of hydrogen use to inform thefeasibility of producing quantities sufficiently large
enough to benefit our energy systems.
Based on the penetration levels shown in column 2 ofTable 1, the demand for H2 was calculated.
Table 1. Act 140 study hydrogen end use estimate
assumptions.
H2 Need
H2 Mass
H2 End Uses
Assumption
Required (kg)Ground
20% Trucks &262,727,245
Transportation
10% Buses
10% of annual
Aviation (SAF)
15,067,000
jet fuel
5% of annual
Electric Power
37,894,099
energyIndustrial
15% hydrogen
839,500(Hawaiʻi Gas)in pipeline

Under the Act 140 study, the feedstock and energy
requirements for producing hydrogen were assessed
for each island by assuming production via biomass
gasification or water electrolysis using renewableenergy. Both of these methods require significant
quantities of materials, energy, and land. Generally
accepted values for conversion of organic feedstockor water into hydrogen (Table 2) were used toquantify the total input requirements.
Table 2. Conversion values for biomass gasification andwater electrolysis to produce hydrogen.
H2 Production Method

Conversion Factor

Gasification of Waste
Gasification of Crops
Water Electrolysis

13-20 kg waste/kg H2
10.5 kg biomass/kg H2
55 kWh/kg H2

These conversion efficiencies with potential island byisland demand were used to determine the capabilityof each island (Oʻahu, Hawaiʻi, Maui, and Kauaʻi) to
produce hydrogen to meet its own needs.
As the most populous island, Oʻahu would havepotential markets for the largest amount of hydrogen

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48

(64% of demand), which poses unique challenges
since Oʻahu also has the lowest hydrogen production
potential due to land constraints.
For H2 production using renewable energy for waterelectrolysis, results indicate that in order to meet theestimated demand for hydrogen the statewide 2045
projected energy required (18,137 GWh) would needto more than double. Put another way, Hawaiʻi would
need to double its projected future electricity
production to produce the equivalent of 326 million
gallons of gasoline to meet demand (Tables 1 and 3).
This scale issue is the most significant barrier tohydrogen playing more than a marginal role indecarbonizing Hawaiʻi.
Table 3. Water electrolysis energy requirement to serve
estimated hydrogen demand by island.
Estimated H2
Energy Required
IslandDemand (kg/yr)(GWh/yr)Oʻahu
207,153,703
11,507
Hawaiʻi
57,006,330
3,166
2,481
Maui
44,665,492
Kauaʻi
17,702,323
983
18,137
Total
326,527,848

While hydrogen has limited potential for
decarbonizing the Hawaiʻi economy, the uses thathave been identified represent significant opportunity
for local business development. To inform thispotential, the HNEI-Telos team then assessed
production
costs,
storage,on-islandtransportation/storage needs, and inter-island
shipping from Hawaiʻi Island to Oʻahu. To support
this work, we also conducted detailed grid modelingusing the 2045 IGP portfolio integrated withelectrolyzers to provide hydrogen for 5% of eachisland’s annual electricity demand.
Several electrolysis integration pathways weremodeled to investigate different grid integration andproduction challenges for H2 to serve electric power
needs. These included:• No H2 Resources: the electrolyzer is added to the2045 IGP grid with no additional resources,
providing hydrogen only when there is surplus
energy on the grid and battery storage is full;• Self-supply: electrolyzers are powered by aseparate portfolio of renewable energy resourcesand does not operate with the grid; and• Grid-supply: the electrolyzers are powered by aseparate portfolio of renewable energy resources,
but those resources are integrated with the grid toalso absorb curtailed energy.
Initial results of the grid analysis for the 2045
portfolio shows that water electrolysis can utilize asignificant amount of the curtailed energy, but it is not
sufficient to meet the 5% of electricity target.
Additional renewable energy resources dedicated tohydrogen production are required to provide enoughhydrogen to meet the 5% firm power need.
Results also indicate that using H2 for electric power
needs will require large-scale storage that would shifthydrogen seasonally. This poses a potential challenge
due to large-scale infrastructure requirements where
utilization will occur only during a few months of theyear. The inclusion of additional end use demand in
the next steps may alleviate this issue since storage
would be used for multiple purposes.
The H2 integration study will determine theoperational requirements for future H2 load to serve
multiple purposes in the Hawaiʻi energy economy andwill inform the community on the feasibility ofintegrating large-scale hydrogen production using
electrolysis and renewables. The study is expected toanswer a number of important questions, such as:• How much H2 storage is required to meet H2 enduse demands? How much storage would be
required for long duration energy storage?
• What impact does H2 load have on statewide
electricity curtailments?
• How much additional renewable energy isrequired to serve H2 production?
• What amount of load flexibility is useful from H2electrolyzers?
• What are the system losses and roundtrip
efficiency of the H2 system, inclusive of
production, transportation, and storage of H2
within the island?
• What impact will these potential hydrogenmarkets have on Hawaiʻi’s GHG emissions?
Funding Source: Energy Systems Development
Special Fund; Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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49

Hawaiʻi Natural Energy Institute Research Highlights
Appendix C: Future Energy Systems
C3: Long Duration Storage Modeling

OBJECTIVE AND SIGNIFICANCE: In Hawaiʻi andacross much of the country, significant attention is
being given to identifying the need and amount ofclean firm renewable energy required for a 100%
clean electricity grid. While much attention has beenafforded to hydrogen and/or biodiesel resources to fillthis need, recent developments in long duration,
multi-day battery energy storage may be anotheroption to provide sufficient firm renewable capacity
to bridge extended periods of low solar and windresource. To evaluate this potential, the HNEI-Telos
team conducted a limited evaluation to determine
whether long-duration storage can provide therequired resource adequacy and capacity.
KEY RESULTS: Preliminary analysis has identified
two key findings. The first is that multi-day batteryenergy storage requires new modeling techniques.
Such methods that are currently being developed by
HNEI-Telos and the broader industry. The second isthat, despite the long duration of discharge capability,
the multi-day storage will likely be constrained tocharge during periods of tight-supply – thus
diminishing the efficacy of providing comparable
firm capacity benefits as a thermal resource.
BACKGROUND: Under other tasks, the HNEI-Telos
team has conducted significant analysis to quantify
the amount of clean firm resources necessary tomaintain reliability in a high renewable powersystem. This analysis was conducted using genericassumptions associated with a “perfect capacity”
resource that is always available when needed(Appendix C1).
To date, all of the battery storage systems being
integrated in Hawaiʻi are relatively short duration,
capable of providing their rated output for only a few
hours. Early battery adoptions on Oʻahu, Maui, andthe Big Island were less than 30-minutes in duration,
providing only grid services to balance fluctuations inwind output. More recent battery additions were 4hour resources, often combined with solar projects,
and added the ability to shift solar generation frommid-day to overnight periods.
However, new storage technologies are underdevelopment across the power industry that are
advancing the capabilities associated with longer
duration batteries. Most notably, Form Energy iscurrently offering a 100-hour iron battery storage
product – potentially allowing for surplus renewablegeneration to shift across days or even weeks.
In 2022, HECO initiated its Stage 3 procurement
process and specifically requested bids for 500-700
MW of firm renewable resources. This procurement,
however, specifically excludes the option for multiday battery storage projects regardless of theirduration because of requirements around fuel storage
and recharging constraints.
This analysis was conducted to understand thetechnical capabilities of multi-day storage resources,
to develop new modeling methods, and to understandwhether or not multi-day battery storage provides
similar characteristics as a thermal resource withliquid fuel capabilities.
PROJECT STATUS/RESULTS: The HNEI-Telos teamis currently conducting the multi-day storage analysis
and anticipate having final results to share with
relevant stakeholders in early 2024. Initial analysis
was conducted to develop new methodologies forevaluating multi-day storage resources. This was
required to overcome modeling challenges associatedwith foresight and predictability of multi-day storage
needs.
Without foresight of the need included in the model,
the battery will discharge completely and will not
recharge because round-trip efficiency losses are sohigh. However, with perfect foresight, the model
over-optimizes the long-duration storage, perfectlyaligning future state of charge with grid needs. For
example, the battery will charge in the days andweeks leading up to a period with sustained low
renewable output and high generator outage
conditions. Both outcomes misrepresent thecapabilities of multi-day storage.
As a result, a new methodology was developed
incorporating different forecast “look-ahead” periodsin the model combined with a new constraint that
requires the multi-day storage to be at or above acertain state of charge at all times, unless it is needed
for grid reliability. This additional energy reserve
ensures that the multi-day storage is available whenneeded, but does not overstate the predictability ofwhen those events may occur. The HNEI-Telos team

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50

is currently testing different levels of these model
parameters and collaborating with multi-day storage
technology providers in industry to ensure themodeling process is robust.

Funding Source: Energy Systems Development
Special Fund and Office of Naval Research

Initial results suggest that the multi-day storage does
not provide comparable benefits for reliability whencompared to a thermal, liquid-fuel generating
resource. This is because the future Oʻahu grid ishighly energy constrained and there may be extended
periods of time where the multi-day storage cannot
recharge. This increases the potential for an event
where the battery storage cannot recharge andredeploy fast enough to be available for subsequent
grid reliability events. The energy challenge isamplified by low round-trip efficiency associatedwith current multi-day battery technologies.

Last Updated: November 2023

Contact: Richard Rocheleau, rochelea@hawaii.edu

Additional research is being conducted to adjustmodeling constraints to properly reflect grid
operations with multi-day storage and the evaluationof multiple grid portfolios with various solar andthermal resources to understand if multi-day storage
can be integrated alongside other firm renewable
resources.

Figure 1. Modeling of multi-day battery storage state of charge (top) against Oʻahu solar resource (middle) andthermal generator outages (bottom), with loss of load events highlighted.
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Hawaiʻi Natural Energy Institute Research Highlights

Appendix C: Future Energy Systems
C4: Analysis of Bill Impacts and Equity of Time-of-Use Rate Design
OBJECTIVE AND SIGNIFICANCE: Time-of-use(TOU) rates – electric rates that vary in price basedon the time of consumption – are currently being
developed and implemented by HECO and the
Hawaiʻi PUC. Under the new rate structure,electricity prices during evening peak demand
periods would be three times more expensive than in
the middle of the day. The intent of these rates is
encourage customers to shift load to hours when solar
generation is plentiful and out of peak demand hours,
which have been historically more expensive. In
theory, this would save customers money while also
benefiting the grid and Hawaiʻi as a whole throughincreased solar integration, reduced oil consumption,
and avoided grid upgrades. The objective of this study
is to assess whether the proposed rates would
equitable, calculate bill impacts of proposed rates,and evaluate potential changes to revenue and costallocation. The results of this study were briefed to
HECO and made available to PUC.
KEY RESULTS: The HNEI-Telos team reviewed
individual 15-minute advanced metering data across
60,000 customers for a single month. The results
showed that large proportions (85+%) of non-PV
customers would be Structural Winners – those who
would get a cheaper bill just from switching to TOU
rates, even without changing their behavior.
Customers with PV, in contrast, would see asignificant increase in monthly bills (62% or$82/month on average) if they were required to switch

to TOU rates. Previous analysis, discussed inAppendix B4, shows that even if the TOU rate
successfully encourages behavior change, it provides
only limited or modest system benefits because muchof the load shifting benefits are provided by grid-scalebattery storage systems. As a result, TOU-induced
behavior change, as currently constructed, does
not provide a meaningful reliability benefit to thegrid. Instead, TOU rates should be designed to moveload across days or to mitigate distribution level
constraints.
BACKGROUND: TOU rates, like those currently being
proposed were first implemented by HECO in 2012
(TOU-R) and the power system has changed
remarkably since then, changing the type of load
shifting needed. From 2023-2025, each of the HECO
grids will see a large increase in battery storage – bothin standalone projects as well as utility-scale solar +storage hybrid projects. These batteries will provide
much of the load shifting needs on the system,
reducing the need for TOU rates.
HECO and the PUC have already committed to large
battery projects in recent procurements and most ofthem are either already operating or underconstruction. These batteries provide much of theload shifting needs on the system, reducing the needfor additional load shifting from TOU rates for theforeseeable future. On Oʻahu, for example, battery
storage will soon reach 400 MW of capacity, overFigure 1. Distribution of bill impacts by non PV customers (left) and PV customers (right).
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

52one-third of evening peak load, with more coming innear-term procurements. The storage deployment onother islands is even more pronounced on a
proportional basis – reaching 60% of peak demand on
Maui and 40% on Hawai’i Island, with additional
storage coming shortly after.
PROJECT STATUS/RESULTS: The results show thatwhile TOU rates will have only limited system
reliability benefits, they will create significant
changes to the way electricity is billed, andpotentially create equity concerns. This could arise ifsome ratepayers switch to TOU rates to reduce theirbill, but the load shift does not have meaningful
economic benefits that can be realized by otherratepayers.
To evaluate this further, the study assessed individual
customer impacts of the proposed TOU rates. The
study found that most non-PV customers would savemoney by switching to the rate without changing their
behavior. The opposite is true for PV customers –they would mostly have to pay more if a switch to
TOU is required.
These findings are highly sensitive to the basedaytime rate. Increasing the base rate by just one cent(from the proposed $0.19/kWh to $0.20/kWh) would
significantly decrease the number of structural
winners. In fact, this change would make morestructural losers than winners.

These large changes in how electricity is billed should
be carefully evaluated for their revenue neutrality.
Assuming that Structural Benefiters switch to theappropriate rate for them, non-PV residential
customers’ total revenue would drop 1.8% anddisproportionately helps high energy users withouta change in behavior. Put simply, TOU rates
introduce a long-term risk of revenue collection forgrid services.
This analysis was paired with the Load Flexibility
modeling effort to develop recommendations for the
future of demand side programs in islands systems
with high amounts of battery storage. While theanalysis showed limited benefits of TOU rates oncebattery storage is added to the system, there are otheropportunities for load flexibility. Principally, as isshown in the Maui load flexibility analysis, there isan opportunity for load shifting induced from TOU
rates to capture the energy arbitrage value thatbatteries could provide. Effectively, the energy
arbitrage benefit is saturated by whichever resource(load shifting or batteries) arrives first.
Given that HECO has already contracted and iscurrently commissioning a large number of grid-scalebatteries in the Stage 1 and Stage 2 procurements, it
is likely that most short-duration load shifting
benefits will already be accrued to battery storage
before meaningful amounts of load flexibility can berecognized.

Figure 2. Percentage of structural winners vs. structural losers with TOU rates, by monthly consumption level.
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

53Regardless of the battery deployment schedule, value
was identified in load flexibility programs thatmodified load consumption based on changing
system conditions rather than a set schedule.
However, such a rate would require moresophistication – from customers, technology
providers, and HECO – to implement.
The analysis evaluated potential benefits of thesemore sophisticated controls, which showed 50%
improvement in capacity benefits when load
flexibility could be dispatched according to thespecific day’s needs. This increased to a 95%
improvement when load could be flexible across aweek, shifting load out of one day (i.e. a cloudy day)and into another altogether (i.e. a sunny day).
A second option to achieve this multi-day flexibility
would introduce a day of week billing (or a “Cloudy
Day Rate”) that effectively prices consumption
higher during low solar days to incent load reduction
when generation would be strained. This however
would only apply to some loads, potentially someelectric vehicle charging, large industrial loads, water
pumping, or other schedulable processes.
Finally, rates designed to avoid distribution-network
upgrades may also provide significant benefits.
Rather than provide broad, system-level benefits,load flexibility could target individual distribution
circuit needs. This could potentially avoid costly
upgrades often attributed to solar PV additions,concentrated EV charging, or new developments.
This would again require either direct load control ora more tailored rate schedule unique to each circuit.
Funding Source: Energy Systems Development
Special Fund and Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

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Hawaiʻi Natural Energy Institute Research Highlights

Appendix C: Future Energy Systems
C5: Modeling and Validating Indoor Air Quality in Hawaiʻi Classrooms
OBJECTIVE AND SIGNIFICANCE: In recent years,
especially since COVID, there has been increased
attention focused on indoor air quality. Under thisproject, HNEI contracted Miller Kelley Architects(MKThink) to evaluate room air quality under
different use cases and different ventilation
typologies. Simulated and measured carbon dioxide(CO2) concentrations were used as a metric for air
quality. The project’s objective was to gain additional
understandingoftheoptimalventilation
configurations to minimize exposure to CO2 or othercontaminants.
KEY RESULTS: This study found that:• At the same air exchange rate, the worst
configuration (vents on same wall) had average
CO2 concentrations that were 52-77% higher thanthe best configuration (vents on opposite walls);• The worst performing configurations also had
more uneven distributions of CO2, resulting inpockets of very high concentrations; and• Using the better performing vent configuration
could allow for a lower ventilation rate while
maintaining good air quality and thus saveenergy.
BACKGROUND: In 2022, MKThink conducted astudy to assess the concentration of CO2 inclassrooms under a variety of physical configurations
and occupancies. This work, involving both fieldmeasurement and computational fluid dynamics(CFD) modeling was intended to identify whether
methods could be developed to inform instructors
about how to maintain high quality indoor air quality
in real time. Results showed some interesting trends
based on air exchange rate (AEC) and location of theexhaust vent compared to the location of the fresh air
inlet vent, but the project stopped short of reaching
defined conclusions that could be used to manage air
quality while minimizing energy use. The major
objective of this follow-on effort was to further
analyze the results of the previous work to provide
additional guidance in the placement of ventilation
system and to identify possible methods to manage
energy from HVAC while maintaining air quality.
PROJECT STATUS/RESULTS: MKThink conducted
additional analysis for a subset of the original study
including four inlet-exhaust location configurations
and three different air exchange rates deemed to bewithin normal operating ranges of commercial
HVAC systems. As expected, for the same ventconfiguration, the average CO2 concentration tracked
monotonically with the air-exchange rate, decreasing
as the AEC (inlet clean air flow) was increased. CFD
modeling of the various configurations also indicatedthat the average CO2 concentration and the variability(difference from average) differed significantly withdifferent inlet-exhaust configurations. Location of
exhaust vents on the opposite wall from the primary
air inlet showed significantly lower average values
and less variability than configurations where theexhaust was on the same wall or a wall perpendicular
to the inlet vent. Unfortunately, the CFD models
assumed a higher human volumetric breathing rate
than a more recent literature search indicates, making
direct comparison of the CFD and previous
measurement in the classroom difficult. This project
is now completed.

Figure 1. Percentage of the room volume exceeding CO2
concentrations (ppm) for vents on the same wall (dottedline) vs vents on opposite walls (solid line).

Funding Source: Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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Hawaiʻi Natural Energy Institute Research Highlights
Appendix D: Grid Technology Development
D1: Coconut Island DC Microgrid

OBJECTIVE AND SIGNIFICANCE: HNEI has
developed a DC-based microgrid test bed on Coconut
Island (Figure 1), home to the University of Hawaiʻi’s
Hawaiʻi Institute of Marine Biology (HIMB). The
project aims to demonstrate and assess the reliability,
resilience, and energy efficiency benefits of a DC
microgrid serving two HIMB buildings. It willcompare the efficiency of serving lighting, cooling,plug loads, and EV charging with AC versus DC
supplied power during normal operations. It will also
support critical building loads during grid supply
interruptions and provide clean transportation options
powered primarily by rooftop solar energy. The
project results and lessons can be applied in future
DC-based microgrids in Hawaiʻi and abroad.

Figure 1. DC microgrid project site, Coconut Island.

BACKGROUND: HIMB aims to serve as a model forsustainable systems, making it an ideal site for a
microgrid test bed centered around renewable energy
technology. This test bed will exemplify a remotearea susceptible to energy disruptions while fulfilling
critical power requirements. The project’s key
objectives encompass: 1) implementing innovative,
efficient, and reliable clean energy technologies; 2)creating a research platform for studying resilient DC
microgrid technologies in a tropical coastal
environment; and 3) advancing solar DC-poweredtransportation solutions, both on land (e-cars) and atsea (e-boats).
HNEI’s Grid System Technologies Advanced
Research Team (GridSTART) partnered with the
Okinawa Institute of Science and Technology, Japanand PUES Corporation, Japan to develop a DCpowered e-car and e-boat (Figure 2), and portable
emergency power source, all using swappable
batteries. The e-mobility solutions are charged withsolar energy from a 6.2 kW rooftop solar PV system
coupled with an 8 kWh battery energy storage system(BESS). HNEI GridSTART also collaborated with the
University of Indonesia (UI). UI designed a new DCDC converter (DCON) that transforms the voltage of

the PV and BESS 48 V DC bus to the 200-350 volts
required by the various DC microgrid loads. The
microgrid provides DC lighting, DC air conditioning,refrigeration, EV charging, and power for criticalbuilding loads, with minimal reliance on the grid
during peak demand times.

Figure 2. Collaborative e-boat and e-car development.

PROJECT STATUS/RESULTS: The DC microgrid
system located in a dedicated electrical room has beensuccessfully installed and commissioned (Figure 3).
This room houses numerous electrical components,
including switches, breakers, controls, a BESS, DCDC converters, and associated wiring. The 6.2 kW
rooftop solar PV system and 8 kWh BESS have been
seamlessly integrated for operation within the DC
microgrid. With the system controller in place andproperly programmed, the DC microgrid is now fully
operational and undergoing performance testing
across a range of scenarios, including resilient supplyof energy to critical load centers in islanded mode.
HNEI GridSTART is using the established microgrid
infrastructure and operational data being collected asa pilot site to initiate extended microgrid researchendeavors and associated new funding opportunities.

Figure 3. DC microgrid components in a dedicatedelectrical room (left) and system’s controller box (right).

Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

56

Hawaiʻi Natural Energy Institute Research Highlights

Appendix D: Grid Technology Development
D2: Advanced Conservation Voltage Reduction Development and Demonstration
OBJECTIVE AND SIGNIFICANCE: HNEI GridSTART
is demonstrating conservation voltage reduction(CVR) as an effective way to conserve energy on a
U.S. Marine Corps (USMC) base in Okinawa, Japan.
CVR works by seamlessly lowering the operating
voltage within the acceptable operating band on
distribution circuits serving customer loads, which
can reduce customer energy use and peak demand.
BACKGROUND: The primary value of CVR
implementation is reduced energy use by more
effectively managing customer service voltage. CVR
is expected to reduce energy consumption by 0.7% to0.9% for every 1% reduction in voltage (i.e., CVR
factor). In close collaboration with USMC Facilities
personnel in Okinawa, seven distribution service
transformers on a branch of the 13.8 kV circuit
serving the Plaza Housing complex were selected for
a CVR field test.

PROJECT STATUS/RESULTS: The VR and associated
CVR controller, as well as the advanced CVR device,
were successfully installed and commissioned in thefield. Communication challenges were addressed to
improve the controller’s performance and datacollection capabilities. HNEI analyzed weekly
measurement data from the USMC Camp Butler teamto estimate the energy savings achieved by
implementing CVR across the downstream
transformers. The CVR assessment determined that
the CVR factor for the feeder section serving theseven transformers ranges from 0.75% to 0.93%,
translating to 1.82 to 2.26 MWh of energy savings permonth.

Figure 2. Voltage profiles with CVR on and off. The tap
position (blue) at 0 indicates CVR is off.

Figure 1. CVR demonstration system architecture.

To control the voltage at downstream service
transformers, the CVR-controlled feeder section isisolated with a new voltage regulator (VR). The VR’sload tap changer (LTC) can shift the voltage profileof the entire feeder down, but it is unable to manage
individual low- or high-voltage points along thefeeder path. This means that the minimum voltage
point along the feeder limits voltage reduction by the
LTC. To achieve greater CVR benefits, HNEI has
patented and field-demonstrated a method of
localized voltage management with an advanced
CVR device. This device uses local measurementsfrom an existing AMI meter to: 1) smooth the voltage
profile by managing and regulating the reactive
power output of inverters; 2) increase voltage at thecritical minimum voltage point regulated by the VR;
and 3) provide maximum CVR benefits for all
customers.

During a typhoon, the VR was disconnected from the
Plaza Housing distribution grid due to an apparent
internal fault. Tests will be conducted to determine if
the VR can be returned to service. If so, HNEIGridSTART will continue collecting field data tofurther assess and evaluate the coordinated operationof the CVR controller, the VR, and the advanced
CVR device at the low voltage point on the feeder.
HNEI GridSTART will also assess the CVR factor of
the loads connected to each transformer tocharacterize the differential CVR benefits acrossalternative classes of end-use loads.

Figure 3. Voltage drop (red) is reduced when theadvanced CVR controller is enabled and reactive power(blue) is dispatched.

Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

57

Hawaiʻi Natural Energy Institute Research Highlights
Appendix D: Grid Technology Development
D3: Hawaiʻi Virtual Power Plant (Hi-VPP) Demonstration

OBJECTIVE AND SIGNIFICANCE: HNEI GridSTART
has developed the Hawaiʻi Virtual Power Plant
Demonstration project (Hi-VPP). The project’s
primary goals are to: 1) assess the economic value andoperational effectiveness of customer-sited battery
and
solar
(BESS+PV)
resources
throughdemonstration and 2) evaluate the technology
application and the value proposition, while
prioritizing alternative use cases based on stakeholderinterests and functional/economic trade-offs. These
resources serve both the customer and the grid whenaggregated as part of a virtual power plant (VPP).
This project is expected to provide key insights into
the economic synergy, optimization of multiple
services under BESS control, and the trade-offs
between simple, low-bandwidth and advanced, highly
coordinated methods of VPP aggregation. Ultimately,
it will help in quantifying the business case for VPPs,
including the value proposition for customer
participation and utility utilization of the same.

Figure 2. System overview of the project.

HNEI GridSTART is utilizing the data collected todevelop a methodology to assess the potential
benefits of customer participation in demand
response programs offered by the Hawaiian ElectricCompany. This evaluation aims to determine theoptimal VPP participation capacity, which in return
could minimize customers’ total electricity bills.

BACKGROUND: Upon the successful conclusion of
the JUMPSmart Maui (JSM) smart grid project
funded by the New Energy and Industrial Technology
Development Organization (NEDO) of Japan, HNEI
negotiated an Equipment Transfer Agreement,
through which HNEI acquired from NEDO
significant grid assets deployed in the JSM project.
HNEI GridSTART capitalized on this acquisition by
utilizing the Sunverge Solar Integration System (SIS)
BESS+PV units located at Haleakala Solar’s businessoffice to conduct this VPP project.
Figure 3. Evaluation process and case studies.

Figure 1. Sunverge SIS BESS + PV units on Maui.

PROJECT STATUS/RESULTS: HNEI GridSTART has
designed control algorithms that integrate withbuilding load forecasts and PV rooftop power
generation forecasts. This integration optimizes the
charge/discharge schedule of BESS units, effectively
reducing electricity costs while ensuring power
requirements are met during utility issued demand
response events (Figure 2).

Through these demonstrations, HNEI GridSTART
aims to test and evaluate the system’s performanceand functionality, thereby acquiring valuable insights
and information for further analysis and decisionmaking. HNEI is currently in the process of preparing
a conference proceeding paper that summarizes ourresearch findings to date.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

58

Hawaiʻi Natural Energy Institute Research Highlights

Appendix D: Grid Technology Development
D4: Assessing Dynamic Response of Converter-Dominated Power Systems

OBJECTIVE AND SIGNIFICANCE: This project aims
to develop local expertise in developing andvalidating modeling and control solutions for today’s
power grid, which is increasingly integrating inverterbased resources (IBR). The overarching technicalgoal is to identify the type and detail of converter
models required to accurately represent power system
dynamical phenomena across multiple time scales forconverter-dominated power systems (CDPS). The
Hawaiʻi power grid serves as an exceptional testbed
for investigating the complex dynamics andtransitional states between CDPS and the broader
power grid. This positions the project as criticallyimportant for Hawaiʻi, as it is poised to drive
significant progress in these areas. The initiative
strategically targets these complexities to enhance thestability, efficiency, and resilience of Hawaiʻi’spower infrastructure, ensuring its readiness for the
evolving demands of a sustainable energy future.
BACKGROUND: HNEI previously collaborated with
the Natural Energy Laboratory of Hawaiʻi Authority(NELHA) on their microgrid analysis project, which
evaluated microgrid options for NELHA’s Hawaiʻi
Ocean Science and Technology (HOST) Park. The
HOST Park features the world’s most extensive
seawater distribution system, which relies heavily on
converter-based generation and complex loads,
including significant variable frequency drives(VFDs), photovoltaic (PV) arrays, and a hydrogenproduction facility equipped with a converter-driven
electrolyzer (198 kW) and mobile storage of up to 300
kg of compressed hydrogen. These features make the
HOST Park an ideal example of a CDPS integrated
with the larger grid. NELHA agreed to collaborate
with HNEI to use the HOST Park’s power system as
the case study for this project. Key project tasks
include: 1) installing new power quality meters anddata collection, 2) generating, calibrating, andvalidating baseline models, and 3) using the models
to study salient dynamics of converter-based
generation and loads within the HOST Park powersystem.
PROJECT STATUS/RESULTS: HNEI, working closelywith NELHA, developed a detailed single-line
diagram of the HOST Park research campus
microgrid (Figure 1). This allowed HNEI researchers
to identify various distribution systems components,
such as transformer sizes and their set-up, and VFDload information for water pumps and PV systemcomponents such as inverters and panels. Following
this effort, HNEI pinpointed three critical locations
and successfully deployed power quality meters onthem, along with all necessary data acquisition
components.

Figure 1. Overview of the NELHA HOST Park’s
electrical load sections (schematic on Google Earthoverlay).

Figure 2 shows the deployed equipment and thestructure for data transfer, as well as the utilized
software for data recording and analysis. A draftmodel of the NELHA research campus microgrid has
been created in PowerFactory. Currently, HNEI is
utilizing the gathered data to calibrate and fine-tune
the model.

Figure 2. Overview of all installed equipment with datatransfer infrastructure and associated software utilized forthe project.

Funding Source: Department of Energy
Contact: Saeed Sepasi, sepasi@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

59

Hawaiʻi Natural Energy Institute Research Highlights
Appendix D: Grid Technology Development
D5: Bidirectional EV Charging Demonstration Project

OBJECTIVE AND SIGNIFICANCE: The main objectiveof this project is to develop, evaluate, anddemonstrate the performance of novel algorithms tooptimize the charge/discharge of shared fleet vehicles
for energy cost minimization. Project experience andresults will not only advance energy research but also
inform the university’s consideration of options suchas the electrification of fleet vehicles, advanced car
share applications, integration of distributed
renewable energy resources on campus, and the
optimal management of campus energy use and cost
containment.
BACKGROUND: HNEI GridSTART is collaboratingwith IKS Co., Ltd. (IKS) on technology development,
testing, and demonstration of advanced control of two
bidirectional electric vehicle (EV) chargers (“HPCS”) on the campus of the University of Hawaiʻi at
Mānoa (UH). The two designated parking stalls,
indicated by the red rectangle, are located adjacent to
the Bachman Annex 6 building indicated by theorange rectangle (Figure 1). The H-PCS wasdeveloped by IKS with support from Hitachi Limited
as part of the earlier JUMPSmart Maui smart griddemonstration project, where GridSTART was one ofthe partners.

Figure 1. Location of bidirectional EV chargers.

Two EVs procured by the project for this research are
currently used by designated university personnel ina car-sharing system accessed via a secure web-based
car scheduling application developed by HNEIGridSTART.
The novel H-PCS control algorithms developed by
HNEI GridSTART first ensures that the sharedvehicles for UH personnel use are efficiently assigned
and readily available for transport needs.
Simultaneously, the autonomous controls deliver
ancillary power and energy services throughintelligent EV charge and discharge commands, attimes allowing the stored energy in the EV batteries
to be strategically withdrawn to minimize the overall

cost of energy supply to UH campus loads. The
autonomous controls may also support theoperational needs of the local utility operator(Hawaiian Electric Company) through the supply ofgrid ancillary services in return for financial
compensation.

Figure 2. Functional system diagram.

HNEI GridSTART’s novel algorithms also
incorporate data fed from state-of-the-art in-housedeveloped forecasts of campus building demand andon-campus solar PV power production. This allows
the system to maximize the use of renewable energy
as the preferred source for EV charging and supply tobuilding loads while minimizing costly energy
purchases from the grid.
PROJECT STATUS/RESULTS: The project was field
operationalized in July 2023, with research focus now
on analyzing system performance data and exploringenhancements of the integrated autonomous control
algorithms hosted on the project's dedicated server.
The system’s energy cost minimization benefit isbeing assessed across a range of alternative building
load and PV profile cases, EV use patterns, charging
modes, and utility tariff structures to explore systemscale up. A vehicle telematic system was successfully
installed to capture real-time car use data while on theroad including EV battery state of charge, vehicle
location, and energy consumption. Data from thetelematic system is planned for enhancement ofpredictive algorithms – enabling more informed
projections of EV use patterns to improve thescheduling of EV charge and discharge controls.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

60

Hawaiʻi Natural Energy Institute Research Highlights

Appendix D: Grid Technology Development
D6: EV Charging Infrastructure Master Plan for USMC Camp Fuji, JapanOBJECTIVE AND SIGNIFICANCE: Aligned with theambitious climate goals outlined in United States
Executive Order 14057, the United States Marine
Corps (USMC) has partnered with HNEI GridSTART
to develop a comprehensive master plan for fleet
electrification and electric vehicle (EV) infrastructure
implementation at Combined Arms Training Center(CATC) Camp Fuji in Gotemba, Japan. This plan will
establish an accessible network of EV charging
stations that are efficient, convenient, and safe, withthe aim of encouraging EV adoption and promoting
sustainability at CATC Camp Fuji.

responsibilities, charging turnaround times, and thecurrent state of EV technology and infrastructure. The
meeting also identified key priority locations for the
installation of EV charging facilities. These selections
considered existing infrastructure, current parking
trends,geographicallimitations,andtheencouragement of EV ownership among Camp
personnel. At these chosen locations, an optimized
combination of DC Fast Chargers and Level 2
chargers was determined based on vehicle types andtheir expected usage demands.

Figure 2. Example of EV charging location from themaster design file.
Figure 1. View of Mt. Fuji from within CATC Camp Fuji
(Source: U.S. Indo-Pacific Command).

BACKGROUND: CATC Camp Fuji, situated at thebase of Mt. Fuji in Gotemba, Japan, is a USMC
installation and training area encompassing various
facilities such as barracks, warehouses, repair shops,
fleet garages, and a military police post. Following
the directives outlined in Executive Order 14057, theCamp is planning to transition its non-tactical vehicle
fleet to EVs in the coming years. Presently, public EV
charging infrastructure in Japan is limited. Therefore,
Camp Fuji’s EV charging network must be
thoughtfully designed to accommodate the specificusage needs of each fleet vehicle, while also
incentivizing the adoption of privately owned EVs atthe camp.
PROJECT STATUS/RESULTS: In August 2023, HNEIGridSTART met with stakeholders at CATC Camp
Fuji to devise a fleet electrification strategy andidentify optimal locations for EV charger deployment
to serve the Camp’s needs. This strategy delineatedthe vehicles most suitable for prompt conversion toEVs, as well as those better suited for conversion as
public EV infrastructure and technology evolve.
Considerations within the electrification strategy
includedrange
requirements,
emergency

As part of the master plan, HNEI GridSTART ispresently evaluating the capacity of Camp Fuji’s
existing electrical infrastructure to accommodate theproposed EV chargers. With the cooperation of Camp
Fuji personnel, HNEI is leveraging historical AMI
data for CATC Camp Fuji to evaluate if the existing
conductors, transformers, and panels can handle theadditional load associated with EV chargers. The
analysis will provide an assessment of theinfrastructure’s current capacity, while also
identifying load patterns linked to seasons, population
changes, or training activities.
Concurrent with the AMI data analysis, HNEI isdeveloping a master planning file that will encompass
the proposed construction drawings for each selected
EV charging infrastructure site. Upon completion,these plans will be used as a technical blueprint for
estimating the potential costs of fleet electrification
infrastructure additions at each location and as a toolfor visualizing the phases of EV infrastructure
integration at Camp Fuji.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

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Hawaiʻi Natural Energy Institute Research Highlights
Appendix D: Grid Technology Development
D7: Advanced Power System Laboratory (APSL)OBJECTIVE AND SIGNIFICANCE: HNEI GridSTART
has designed and equipped its new Advanced Power
System Laboratory (APSL) to conduct research,development, test, and evaluation (RDT&E) insupport of power systems modernization andrenewable energy integration. The APSL has a highly
flexible architecture and is the first laboratory of its
kind in Hawai‘i – able to test AC and DC devices,
systems, and microgrids within a managed field
representative electrical environment. The lab will
significantly enhance HNEI’s ongoing researchendeavors by providing a state-of-the-art test
environment that extends its RDT&E capabilities todeliver next-generation smart grid technologies.
BACKGROUND: The APSL comprises of significant
components, including three AC/DC equipment test
bays and a 35 kW rooftop PV system connected tofour advanced PV inverters with grid support
functions (Figure 1). This PV system serves a dual
purpose, supporting the lab’s research needs andassisting the University of Hawai‘i in achieving its
net zero energy consumption goal. Additionally, thelab hosts a real-time grid simulator connected to a 30
kVA power amplifier, facilitating power hardwarein-the-loop (HIL) testing. The power HIL systemenables researchers to evaluate electrical power
equipment as a unit under test (UUT) in a real-time
simulated grid environment.
The three modular AC/DC test bays (see Figure 2)
have been designated for evaluating advanced
functions, communications and controls of various
UUT. These include advanced PV inverters, EV
chargers those with vehicle-to-grid (V2G) andvehicle-to-home (V2H) bidirectional power flow
capabilities, battery energy storage systems (BESS),
power monitoring and edge computing devices, AC

or DC loads/appliances and load control devices, andvoltage management equipment, among other
innovative technological solutions.

Figure 2. Three AC/DC equipment test bays.

PROJECT STATUS/RESULTS: The design, permitting,and construction of the electrical infrastructure of the
APSL are now complete, rendering the lab available
for use. In addition, there is an ongoing procurement
process for a microgrid control system thatencompasses integrated microgrid modeling tools andthe capability to seamlessly integrate with the APSL’s
existing power HIL system. This integrated system
will empower HNEI to introduce a comprehensive
microgrid design and control training curriculum
aimed at power system engineers across the AsiaPacific region. Furthermore, the APSL and its power
HIL equipment will be employed in tandem with
HNEI GridSTART’s field-deployed microgrid testbed
on Coconut Island for the development and testing ofnew, resilient microgrid control algorithms. Thesealgorithms will address dynamic load management,
facilitated by a recently secured U.S. DOE-sponsoredresearch grant of approximately $1 million.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Figure 1. HNEI GridSTART’s Advanced Power System Lab architecture.
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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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62

Hawaiʻi Natural Energy Institute Research Highlights
Appendix E: Alternative Fuels
E1: Sustainable Aviation Fuel Production

OBJECTIVE AND SIGNIFICANCE: Commercial
aviation in Hawaiʻi currently uses nearly 700 million
gallons of jet fuel per year, all of it is derived frompetroleum. The University of Hawaiʻi (UH) is amember of the Federal Aviation Administration’s(FAA) Aviation Sustainability Center (ASCENT)
team of U.S. universities conducting research on
production of sustainable aviation fuels (SAF). UH’s
specific objective is to conduct research that supports
development of supply chains for alternative,
renewable, sustainable, jet fuel production in
Hawaiʻi. Results may inform similar efforts in othertropical regions.
BACKGROUND: This project was initiated in October
2015 and is now continuing into its 9th year.
Activities undertaken in support of SAF supply chain
analysis include:• Conducting literature review of tropical biomass
feedstocks and data relevant to their behavior inconversion systems for SAF production;• Engaging stakeholders to identify and prioritize
general SAF supply chain barriers (e.g. access tocapital, land availability, etc.);• Developing geographic information system(GIS) based technical production estimates of
SAF in Hawaiʻi;• Developing fundamental property data on
biomass resources; and• Developing and evaluating regional supply chain
scenarios for SAF production in Hawaiʻi.

identified and reported. Technical estimates of land
resources that can support agricultural and forestrybased production of SAF feedstocks have been
completed using GIS analysis techniques. Samples
from Honolulu’s urban waste streams and candidate
agricultural and forestry feedstocks have beencollected and subjected to physicochemical property
analyses to inform technology selection and design of
SAF production facilities.

Figure 2. Commercial jet fuel consumption in Hawaiʻi.

Fuel Properties of Construction and Demolition
Waste Streams
A sampling and analysis campaign was undertaken tocharacterize fuel properties of construction anddemolition waste (CDW) streams on Oʻahu.
Complete results were summarized and published inConstruction and Demolition Waste-Derived
Feedstock: Fuel Characterization of a Potential
Resource for Sustainable Aviation Fuels
Production in the Frontiers in Energy Research
journal.

Figure 1. Commercial and military jet fuel use in 2015.

As shown in Figure 3, although the combustible
fraction of the samples have elevated ash levels
compared to clean biomass materials, their heating
values were comparable, indicating the presence of
higher energy density materials. As with most refuse
derived fuels, the amount of ash in the fuel and its
composition is of particular importance – since ash
impacts energy facility operations, maintenance, andemissions.

PROJECT STATUS/RESULTS: Literature reviews ofboth biomass feedstocks and their behavior in SAF
conversion processes have been completed andpublished. Based on stakeholder input, barriers to
SAF value chain development in Hawaiʻi have been

Tests of clean wood fuel from the invasive species(Leuceana spp., common name koa haole) and CDW
material were conducted at a commercial gasification
technology provider facility to evaluate productcomposition and yields and identify contaminants

Total use:
678.4M gallons

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63

(Figure 4). Test reports for koa haole (“Gasificationof Leucaena leucocephala Stemwood”) and CDW(“Gasification of Synthetic CDW 1”), respectively,
are available on HNEI’s website. The test results
detail the reactor operating conditions, fuelcharacteristics, concentrations of major permanent
gas species (H2, CO, CH4, CO2), and concentrationsof inorganic species present as contaminants in the
product gas stream (H2S, NH3, HCl, As, Cd, Cr, Pb,
Mg, P, K, Se, Na, Z, Hg). The increases of As, Pb,
and Cr concentrations in the CDW product gas
compared to clean wood product gas were notable, inthe case of arsenic increasing from ~1 part per billion(ppb) to ~200 ppb. The data indicate that managing
the gas quality through feedstock treatment/blendingor product gas cleanup will be required.

below3. Waste amounts generally scale according topopulation, with Honolulu having the largest total
despite the use of waste for fuel in the HPOWER
power plant. Integrating solid waste management andfuel production with a view of treating the state as asingle management unit rather than four individual
county units could be a beneficial approach to meet
waste management, energy resiliency, andgreenhouse gas abatement goals. Analysis of thisintegrated approach will be conducted in the coming
year.

CDW
Construction wood
Woody biomass25

Ash content (%)

14
12
10
8
6
4
2
0

CDW
Construction wood
Woody biomass

Higher Heating Value (MJ/kg)

16

20
15
10

Figure 4. Relative ratios of elements in present in fuels toratios in the product gas stream.

5

Future work with ASCENT partners includes:• Analysis of feedstock-conversion pathway
efficiency, product slate (including co-products),
maturation;• Scoping of techno-economic analysis (TEA)
issues;• Screening level greenhouse gas (GHG) life cycle
assessment (LCA);• Identification of supply chain participants andpartners;• Continued stakeholder engagement;0

Figure 3. Ash content (left) and heating value (right) of
the combustible fraction of CDW compared toconstruction wood and woody biomass.

Utilizing urban waste resources as feedstock for SAF
production has the advantages of both reducing
amounts of material entering the limited landfill spaceand reducing dependence on imported energy. A
statewide assessment of urban waste resources
currently entering landfills is summarized in Table 1

Table 1. Summary of combustible waste materials currently entering landfills (tons per year).

CountyNon-food biomass
Plastics and textiles
CDW
Urban Total

Maui
111,151
40,832
151,983

Kauaʻi
43,27913,90457,183

Hawaiʻi120,346
27,616
147,962

Honolulu
22,2076,440
208,000
236,647

Total
296,983
88,792208,000
593,775

3 Adapted from Turn, S.Q., R.B. Williams, and W.Y. Chan. 2022. Resources for renewable natural gas production: A Hawai‘i case study.
Environmental Progress & Sustainable Energy. e14002. https://doi.org/10.1002/ep.14002.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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64• Acquiring transportation network and otherregional data;• Evaluating infrastructure availability; and• Evaluating feedstock availability.
Exploration of Biomass Feedstocks for HawaiʻiFigure 5 shows the breakdown of land use of thenearly 2 million acres of agricultural lands in
Hawaiʻi 4. With the shuttering of much of the canesugar and the pineapple industries, this total has
dropped further. Bringing agricultural lands back into
production can support diversification of theeconomy and support rural development. Biomass
feedstocks for sustainable aviation fuel production
are options that can contribute to this revitalization.
This work was summarized and published in Review
of
Biomass
Resources
and Conversion
Technologies for Alternative Jet Fuel Productionin Hawaiʻi and Tropical Regions in the Energy andFuels journal.
The EcoCrop model was used to complete anassessment of plant production requirements to agroecological attributes of agricultural lands in the State.
Land use constraints included agricultural zoning,land capability classes (an indicator of soil quality),
slope, service by irrigation systems, and current
agricultural activities. The analysis focused on sites

capable of rain-fed production to avoid using irrigatedlands that could support food production. Oil seedcrops, woody crops, and herbaceous crops were allconsidered; an example is shown for a eucalyptus
species (Figure 6).
The EcoCrop model provides an estimate of eachenergy crops’ productivity across the agriculturallandscape. Aggregated yield of biobased feedstockand conversion efficiency from feedstock to final
energy product were used as the basis for SAF
technical potential estimates under four scenarios:• Scenario 1 - agricultural zoning, slope less than
20%, land capability class 1 to 6
• Scenario 2 - agricultural zoning, slope less than
20%, land capability class 1 to 6, excluding land
serviced by irrigation systems,• Scenario 3 - agricultural zoning, slope less than
20%, land capability class 1 to 6, excluding land
serviced by irrigation systems and land currently
in agricultural use, and• Scenario 4 - agricultural zoning, slope less than
20%, land capability class 1 to 6, excluding land
serviced by irrigation systems and land currently
in agricultural use other than pasture.
All scenarios assume a EcoCrop suitability index>0.5 on a scale of 0 to 1 using rainfed conditions.

Figure 5. Breakdown of agricultural land use in Hawaiʻi; in 2015, approximately 100,000 acres were harvested.
4 Adapted from data in Melrose, J., R. Perroy, S. Cares. 2015. Statewide agricultural land use baseline 2015. Prepared for the Hawaiʻi
Department of Agriculture. Honolulu, Hawaiʻi.

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65Figure 6. EcoCrop assessment of Saligna, Eucalyptus.

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66Results of the analyses are shown in Figure 7. Notethat the results are not mutually exclusive, i.e. thesame land area may be included in the estimates ofmultiple crops. Scenario 1 includes the greatest landarea and this is reflected in highest annual SAF
production potential estimates, of up to ~100 million
gallons. Scenario 2 removes any land service by anirrigation system from the analyses, resulting in a
reduction in potential to a ~80 million gallons.
Scenario 3 further restricts available lands by
excluding those under production identified in a study
conducted by the University of Hawaiʻi at Hilo (UHHilo) for the Hawaiʻi Department of Agriculture 5,
resulting in SAF production potential estimates <40
million gallons per year. Scenario 4 considers the dual
use of land to support energy crops and pasture byincluding pasture lands identified in the UH HiloBaseline report. This results in maximum estimates of~70 million gallons per year. A report detailing theseresults is currently being drafted.
Pongamia production logistics
EcoCrop energy crop modeling identified pongamia
as having the greatest oil production potential basedon suitable growing area and yield. The geographic
distribution of suitable growing areas across the stateprovides an opportunity to select pongamia primaryprocessing sites that minimize transportation costs.
Seeds in their pods would be harvested andtransported to a primary processing location where
the seed and pod could be separated, oil could be
extracted from the seed, and oil and de-oiled seed

Figure 7. SAF potential (million gallons per year) for 13 energy crop feedstocks under four scenarios: (a) agriculturalzoning, slope less than 20%, (b) agricultural zoning, slope less than 20%, exluding land serviced by irrigation systems,(c) agricultural zoning, slope less than 20%, exluding land serviced by irrigation systems and land currently inagricultural use, and (d) agricultural zoning, slope less than 20%, exluding land serviced by irrigation systems and land
currently in agricultural use other than pasture. All scenarios assume a EcoCrop suitability index >0.5 on a scale of 0 to
1 using rainfed conditions.
5 Melrose, J., R. Perroy, S. Cares.

Agriculture. Honolulu, Hawaiʻi.

2015. Statewide agricultural land use baseline 2015. Prepared for the Hawaiʻi Department of

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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67cake could be upgraded. Land zoned for industrial use(brownfield site) on each island was considered as
potential primary processing sites. Greenfield sites
were also considered – identified as land zoned for
agriculture with slope less than 5%, and a minimum
contigous area of 125 acres. This would accomodate
space needed for processing, storage, and possible
colocation of complementary industries utilizing thede-oiled seedcake and pod to develop coproducts. A
tonne-kilometer value, Tkmi, was calculated for all i
candidate processing location using equation (1).
𝑇𝑇𝑇𝑇𝑇𝑇𝑖𝑖 = ∑𝑛𝑛𝑗𝑗=1 𝑚𝑚𝑗𝑗 ∙ 𝑑𝑑𝑗𝑗

(1)

Where mj is the mass of seed pod harvested at a
production location j, dj is the distance traveled overthe existing road network between production
location j to the processing site i, and n is the numberof pongamia production locations. Production
locations were based on analysis using a 1 km x 1 km
grid. A relative index, Cik, shown in equation (2), wasused to compare Tkm values across islands.
𝑇𝑇𝑇𝑇𝑇𝑇 −𝑇𝑇𝑇𝑇𝑇𝑇

𝑚𝑚𝑚𝑚𝑚𝑚𝐶𝐶𝑖𝑖𝑖𝑖 = �𝑇𝑇𝑇𝑇𝑇𝑇 𝑖𝑖 −𝑇𝑇𝑇𝑇𝑇𝑇
� (2)𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑘𝑘

where Tkmmin and Tkmmax are the minimum andmaximum Tkm values, respectively, for island k.
Candidate sites for Scenario 1, ranked from lowest(Cik=0) to highest (Cik=1) value, are shown in Figures
8 and 9 for brownfield and greenfield locations,
respectively.
Greenfield site options are more numerous thanbrownfield locations and may afford reductions intransportation requirements as shown in the figures.
Brownfield sites are anticipated to offer access to preexisting utilies that could reduce costs of developing
the processing facilities. The locations for minimum
cost sites depend on the production scenarios for
pongamia. Pongamia production system planning
would require verification of industrial zoning,
farmer acceptance of pongamia production,community acceptance, and economic viability of allvalue chain participants. Continued systemevaluation is planned moving forward.

Evaluation of Pongamia
Of the sustainable aviation fuels currently approved
by ASTM and the FAA, those based on the use of oils
derived from plants and animals have the highest SAF
yield and the lowest production costs.
Invasiveness Assessment
Pongamia (Millettia pinnata) (Figure 10) is a tree,
native to the tropics, that bears an oil seed and has
plantings established on Oʻahu. Under this project, anobservational field assessment of trees in sevenlocations on Oʻahu was conducted by Professor
Curtis Daehler (UH Dept. of Botany) to look fordirect evidence of pongamia escaping from plantingsand becoming an invasive weed. Although somepongamia seedlings were found in the vicinity ofsome pongamia plantings, particularly in wetter,
partly shaded environments, almost all observed
seedlings were restricted to areas directly beneath the
canopy of mother trees. This finding suggests a lackof effective seed dispersal away from pongamia
plantings. Based on its current behavior in the field,
pongamia is not invasive or established outside ofcultivation on Oʻahu. Because of its limited seeddispersal and low rates of seedling establishment
beyond the canopy, risk of pongamia becoming
invasive can be mitigated through monitoring andtargeted control of any rare escapes in the vicinity ofplantings. Seeds and seed pods are water dispersed,
so future risks of pongamia escape and unwanted
spread would be minimized by avoiding planting atsites near flowing water, near areas exposed to tides,
or on or near steep slopes. Vegetative spread by root
suckers was not observed around plantings on Oʻahu,
but based on reports from elsewhere, monitoring forvegetative
spreadaroundplantations
isrecommended; unwanted vegetative spread might
become a concern in the future that could be
addressed with localized mechanical or chemical
control. A detailed technical report titled“Observational Field Assessment of Invasiveness of
Pongamia (Millettia pinnata), A Candidate Biofuel
Crop in Hawai‘i” summarized this work and isavailable on HNEI’s website.

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68Figure 8. Results of analysis to identify locations to minimize transportation costs of harvested pongamia seed pods to acentral brownfield processing site. Blue areas are zoned for agriculture, have slope less than 20%, have land capability
class ratings of 1 through 6, and have EcoCrop suitability values of 1.0 for pongamia under rainfed conditions. Potential
brownfield processing locations, shown as colored circles, are zoned for industrial use. The star on each island identifies
the location of Tkmmin corresponding to Cik = 0.
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69Figure 9. Results of analysis to identify locations to minimize transportation costs of harvested pongamia seed pods to acentral greenfield processing site. Blue areas are zoned for agriculture, have slope less than 20%, have land capability
class ratings of 1 through 6, and have EcoCrop suitability values of 1.0 for pongamia under rainfed conditions. Potential
greenfield processing locations, shown as colored circles, are zoned for agriculture, have slopes ≤5%, and have 125 acres(50 hectares) of contiguous area. The star on each island identifies the location of Tkmmin corresponding to Cik = 0.

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70Figure 10. Locations and images of Pongamia.

Figure 11. Pathways from Pongamia seed pods to fuel.

Fuel Properties
Pongamia is a potential resource for renewable fuelsin general and sustainable aviation fuel in particular.
This physicochemical properties of reproductive
material (seeds and pods) from pongamia trees grownin different environments at five locations on Oʻahu
were characterized (Figure 11). Proximate andultimate analyses, heating value, and elemental
composition of the seeds, pods, and de-oiled seedcake were determined. The oil content of the seeds
and the properties of the oil were determined using
American Society for Testing and Materials (ASTM)
and American Oil Chemist’s Society (AOCS)
methods. The seed oil content ranged from 19 to 33% wt. across the trees and locations. Oleic (C18:1)
was the fatty acid present in greatest abundance (47to 60 % wt) and unsaturated fatty acids accounted for
77 to 83 % wt of the oil. Pongamia oil was found tohave similar characteristics as other plant seed oils
(canola and jatropha) and would be expected to bewell suited for hydro-processed production ofsustainable aviation fuel. These results were
published in Fuel Properties of Pongamia (Millettia
pinnata) Seeds and Pods Grown in Hawaiʻi in the
ACS Omega journal.

Coproduct Development
Additional studies were devoted to developing
coproducts from pongamia pods. Leaching andtorrefaction experiments were performed to remove
inorganic constituents and reduce the oxygen content
of the pods (Figure 12). A 23 factorial design of theleaching treatment determined the impacts of process
operating parameters (i.e. rinse water temperature,rinse duration, and particle size) on the compositionand physicochemical properties of the pods and thewater. The higher heating value of the pods was foundto increase from 16 to 18-19 MJ/kg after leaching,while the ash content was reduced from 6.5% to as
low as 2.8%wt, with significant removal of sulfur (S),chlorine (Cl), and potassium (K). The chemical
oxygen demand, non-purgeable organic carbon, andtotal nitrogen of the post-experiment leachates were
all found to increase with the rinse water temperatureand rinse duration but decrease with the increase ofparticle size. Leached pods were further processed via
torrefaction and the targeted mass and energy yields,~70% and 85%, respectively, were reached at aprocess temperature of 270°C. The S, Cl, and K
contents of the leached, torrefied pods were found tobe lower than that of the raw pods. The reuse ofleachate on successive batches of fresh pods showedthat ash removal efficiency was reduced after threecycles, although some removal was possible through15 cycles.
Pongamia pod leaching processes and pod
torrefaction processes were summarized andpublished in Water leaching for improving fuelproperties of pongamia Pod: Informing process
design and Upgraded pongamia pod via

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71torrefaction for the production of bioenergy, bothin the Fuel journal, respectively.

Figure 12. Laboratory scale leaching and torrefaction test
equipment.

Other Feedstocks
Other potential feedstocks for Hawaiʻi, kukui(Aleurites moluccanus) and kamani (Calophyllum
inophyllum) nut oils, were also explored. The oilcontent of the kukui nuts is ~60% wt, which is ~2030% wt higher than that of pongamia seeds andkamani nuts. The unsaturated fatty acids, however,accounted for ~90 % wt of the kukui nut oil, slightly

higher than that of kamani nut (~75% wt) andpongamia seed oil. Kukui and kamani nut oil aredifferent from the pongamia seed oil, in that the
primary fatty acid is linoleic acid (C18:2). The resultsof the study conducted on kukui were published inComprehensive Characterization of Kukui Nuts
as Feedstock for Energy Production in Hawaiʻi in
the ACS Omega journal.
Summary of SAF Production Potential Estimates
Table 2 compares the SAF technical production
potential from urban wastes, oil seeds, grasses, andtrees by island with 2018 petroleum jet fuel use data
for the state. The use of SAF is currently limited to≤50% blends with petroleum jet fuel. SAF production
potentials from urban wastes range from 1 to 12% of2018 petroleum jet fuel use by island. Energy crop
production potentials range from 0.5 to 108.8% of2018 petroleum jet fuel use by island. The largest
mismatch for urban waste and energy crop potentials
occurs in Honolulu, which has the highest jet fuelconsumption. The energy crop SAF production
potentials are more closely aligned to current
petroleum jet fuel consumption on the outer islands
under the most optimistic production scenario (seeFigure 7a). We would like to note that totals in Table
2 do not include production on Molokaʻi and Lānaʻi.
Funding Source: Federal Aviation Administration;
Energy Systems Development Special FundContact: Scott Turn, sturn@hawaii.edu
Last Updated: November 2023

Table 2. Summary of 2018 jet fuel use by island and technical production potentials from urban resources andenergy crops (all values in million gallons per year, numbers in parentheses are % of 2018 island fuel use).

Maui
Kauaʻi
Hawaiʻi
Honolulu
Total
81
33
50
513
677
Sustainable Aviation Fuel Technical Potentials
Urban Waste
6 (7.3)2 (6.7)
6 (11.5)
9 (1.8)23 (3.4)
Energy Crop, Scenario 1, Suitability >0.5, Not Mutually Exclusive
Oil Seed
14 (17.7)
13 (40.0)50 (100.7)
9 (1.7)86 (12.8)
Trees
16 (19.8)
15 (44.6)
54 (108.8)
9 (1.7)94 (13.9)
Grasses8 (9.7)15 (45.2)
28 (56.1)
3 (0.5)53 (7.9)
Fuel Burn 2018

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72

Hawaiʻi Natural Energy Institute Research Highlights

Appendix E: Alternative Fuels
E2: Investigation of Waste-Based Feedstocks for Sustainable Aviation Fuel Production
OBJECTIVE AND SIGNIFICANCE: The aviationindustry (civilian and military) faces significant
challenges due to dependence on petroleum jet fuels
and limited opportunity for electrification.
Sustainable aviation fuels (SAF) from renewable
resources provide alternatives to petroleum fuels andhave added environmental benefits.
This research investigates the behavior of urban solid
waste under possible gasification environments
defined by temperature, pressure, and reactive
environment. Results of this project can be used to
inform participants in the urban solid waste tosustainable aviation fuel value chain, fuel suppliers,
technology providers, gasification system operators,
and research and development funding agencies.
Project success will support the production, adoption,and use of sustainable bio-based aviation fuel – amuch needed alternative to petroleum legacy fuels.
BACKGROUND: Feedstocks for SAF production
include fiber, sugar, starch, and oil available from theforestry and agricultural sectors, and from urban solid
wastes (USW). The fiber fraction of USW can be used
to feed any of the downstream technology pathways
leading to SAF products. EPA data shows that morethan 100 million tons of combustible material arelandfilled in the U.S. annually 6. An estimation also
reported that ~8.5 billion tons of waste materials
could be mined from the existing U.S. landfills 7.
Although the use of USW for SAF feedstock showshigh potential, it is not without challenges. USW may
include municipal solid waste (MSW) andconstruction and demolition waste (CDW) that areheterogeneous in composition. A recent sampling
program at a CDW landfill in Nānākuli, Hawai‘ishowed that CDW samples may contain ash
approaching 10 wt% of fuel and ~25 elements ofinterest. In comparison, the ash in clean woodaccounts for less than 1 wt% of fuel and contains ~12elements of interest.

Gasification and gas cleanup of urban solid waste canbe modeled as a series of thermochemical and phaseequilibria steps defined by the thermodynamic state
points of unit operations. Results can identify
opportunities to improve gasification system
performance by 1) managing urban solid waste
components entering the gasification process, 2)
guiding selection of reactor materials, and 3) avoiding
operating conditions that result in ash deformation or
pollutant formation. Under gasification conditions,ash present in the fuel may deform to produce vapors
or liquid slags. The latter causes operating difficulties
in the reactor, agglomerating bed material, andreducing fluid bed performance. The former may
deposit on heat exchange surfaces, deactivate
downstream catalysts, or contribute to pollutant
formation. Understanding the behavior of ash
elements under gasification conditions can provide
information to further reactor design, processoptimization, and strategies to mitigate the negative
impacts of ash elements.
PROJECT STATUS/RESULTS: A literature review was
conducted to identify the typical ranges for theelemental compositions of available waste-based
fuels.
A sampling and characterization campaign
determined the detailed composition of CDW
materials mined from the PVT Land Company
landfill over a period of time 8. These data were used
as input to FactSage for thermochemical equilibrium
calculations to investigate:• The fate of ash from CDW fuels undergasification at different temperatures, pressures,and in different reactive environments (oxygen,steam, and oxygen-steam);• Possible interaction between ash elements andcommon fluidized bed materials or oxygen
carriers in chemical looping systems;• Possible interaction and/or deactivation of ash
element and common catalysts; and6 EPA. (2022) National overview: Facts and figures on materials, wastes and recycling. https://www.epa.gov/facts-and-figures-about-materials-waste-and-recycling/national-overview-facts-and-figures-materials.
7 Powell, J.T., J.C. Pons, and M. Chertow (2016) Waste Informatics: Establishing characteristics of contemporary U.S. landfill quantities andpractices. Environmental Science & Technology 50, pp 10877-10884.
8 Bach Q-V, Fu J, and Turn S (2021) Construction and Demolition Waste-Derived Feedstock: Fuel Characterization of a Potential Resource
for Sustainable Aviation Fuels Production. Frontiers in Energy Research 9:711808.
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

73• Strategies to control and/or remove gas phase
inorganic species (e.g. As) from product gas
using sorbents.
#181227#190718#190305#190808#190405#190213#190801#190328#190116#190725#190312#190815

CCA Wood

Constr. Wood 1

Constr. Wood 2

DougFir

Eucalyptus

Al

Cl

Mg

S

Si

4

3

2

1

Ca

Fe

Na

Ti

example, when feedstock was gasified underoxygen, steam, and steam + oxygen conditions,
23 to 34% of the arsenic present in the feedstock
was predicted to partition to the gas phase productstream. These values were reduced to 12% if bed
material was included in the equilibrium
gasification process calculations.
• Olivine bed material can help capture a portion ofarsenic during the gasification process due to thepresence of nickel in its chemical composition.
• Left unmanaged, arsenic species in the productgas stream are predicted to contribute todeactivation of Fe and Co based FT catalysts indownstream processes.
• It is possible to remove arsenic compounds bycooling hot product gas, however, cooling may
also result in the condensation of high molecularweight compounds (tar).
• Copper and nickel can be employed as arsenic
sorbents with sorptive capacity directly linked tothe metal mass.
The study employed equilibrium calculations toanalyze gasification and subsequent downstream
processes. It is worth noting that real gasification
systems are dynamic and considerably more complex
to simulate. Experimental validation of theseprocesses is thus recommended for further study.

2

1

Funding Source: DLA Energy0Contact: Scott Turn, sturn@hawaii.edu;
Quang-Vu Bach, qvbach@hawaii.edu

-1
Ag

Ba

Ce

Co

Mo

Ni

Pd

Rb

Ru

Sb

Tb

V

W

Zr

Element

Last Updated: November 2023

Figure 1. Element concentrations (log10 of ppm) in 12
CDW samples and five reference material samples.

The project was completed in 2023 and the significant
findings and outcomes include:• Establishing a database for fuel properties ofwaste-based feedstock.
• The available data revealed that fuel property
values of waste-based feedstocks varied widely,
indicating the importance of site specificfeedstock analysis in system design.
• After gasification, arsenic from waste-based
feedstocks was present in the gas phase atdifferent levels depending on the use of
gasification agents and bed materials. For
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74

Hawaiʻi Natural Energy Institute Research Highlights
Appendix E: Alternative Fuels
E3: Advanced Fuel Characterization and Development

OBJECTIVE AND SIGNIFICANCE: The objective of
this project is to systematically assess the impacts oftrace quantities of heteroatomic organic species(HOS) on fuel properties and to advance thedevelopment of high-energy density (HED) fuels for
future transportation applications.
New analytical methods under development can 1)
evaluate the composition of fuels currently in use andthose stored as strategic reserves and 2) investigate
the impacts of crucial nitrogen and sulfur containing
compounds and additives on fuel properties.
Comprehensive fuel composition information can befurther employed to replace costly experimental
measurements
bycalculating
variousphysicochemical
properties
ofconventional
petroleum and alternative fuels. The knowledge
gained in this project will enhance our understandingof how HOS and fuel additives impact fuel stability
and physicochemical properties, guide efforts topreserve fuel quality, reduce the cost of fuelcharacterization, and advance the development ofalternative HED fuels.

In August 2018, a 2D-GC expanded the fuellaboratory’s ability to identify and quantify fuelconstituents present in trace amounts (≤1 ppm). The
HNEI 2D-GC employs two injectors and threedetectors, i.e. mass spectrometer (MS), nitrogenchemiluminescence
(NCD)
and
sulfurchemiluminescence (SCD), to analyze fuelcomponents and HOS with a single injection event.
Neat fuels can be injected directly without requiring
solvent dilution. Data generated using this instrument
is used as input to the conductor-like screening model
for realistic solvation (COSMO-RS) method. These
calculation techniques predict physicochemical
properties of petroleum and alternative fuels based on
their individual compositions and guide the design of
HED fuels.

BACKGROUND: Liquid fuels are, by nature,chemically complex and many fit-for-purpose andstability issues are associated with trace quantities of
HOS inherent in the parent feedstock or employed asadditives. Identification and quantitation of HOS andadditives are challenging due to their low
concentration and complex composition of the fuelmatrix – necessitating the development andutilization of advanced analytical methods, such as
two-dimensional gas chromatography (2D-GC).
In 2012, HNEI established a fuel laboratory with thecapabilities encompassing essential analysis requiredby ASTM and military fuel specifications. Present
capabilities include prediction of fuel properties using
empirical
andphenomenologicalmodeling
techniques. Research conducted in the fuel laboratory
includes investigating the impacts of long-term
storage, oxidative conditions, contaminants,
additives, and other factors on conventional andalternative fuels and their blends. Computational
methods to predict fuel properties support
experimental efforts and contribute to theadvancement of future transportation fuels.

Figure 1. Comprehensive 2D-GC analysis of F-76 diesel
fuel with MS, NCD, and SCD.

PROJECT STATUS/RESULTS: HNEI is currently
collaborating with personnel from the Navy
Technology Center for Safety and Survivability at theNaval Research Laboratory, Washington, DC on 2D-

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75

GC applications for sulfur-containing compounds(SCCs) analysis.
Past activities under this project included: 1)
participation in standard method development for
nitrogen-containing compounds (NCCs) analysis
with a 2D-GC-coupled NCD; 2) determining theimpacts of antioxidant concentration on preserving
fuel quality; and 3) COSMO-RS prediction of fuelboiling point, vapor pressure, density, andcompatibility with fuel system polymers.
Currently, HNEI’s activities include:• Determining fuel hydrocarbon matrix;• Exploring the influences of SCCs and NCCs on
the degradation of fuel antioxidants (AOs) andthe consequent impacts on fuel stabilities;• Developing standard methods for identificationand quantification of SCCs by using 2D-GC
coupled to SCD and high resolution (HR)orbitrap MS;• Calculating various fit-for-purpose properties
based on the 2D-GC compositions of fuels; and• Developing high energy density and stability
fuels based on quantum chemistry andthermodynamic calculations.
To date, this project has produced the following
publication:• 2023, J. Fu, P.K. Le, S.Q. Turn, Impacts ofantioxidants on stability of biodiesel derived
from waste frying oil, Biofuels, Bioproducts andBiorefining, Vol. 17, Issue 6, pp. 1496-501.
Funding Source: Office of Naval ResearchContact: Scott Turn, sturn@hawaii.edu;
Jinxia Fu, jinxiafu@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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76

Hawaiʻi Natural Energy Institute Research Highlights
Appendix E: Alternative Fuels
E4: Novel Biocarbons

OBJECTIVE AND SIGNIFICANCE: Biomass can be arenewable resource for the production of energy,
fuels, chemicals, and materials. The goal of thisproject is to develop processes to 1) produce biochars
and biocarbons from biomass feedstocks and 2)
control and tune their properties by selection of
biomass feedstocks and process conditions.
Slow pyrolysis is a thermochemical process thatconverts biomass into solid carbonaceous materials.
The maximum temperature used during slow
pyrolysis will dictate the extent to which the material
is carbonized. Low temperature slow pyrolysis (200500°C) results in the formation of biochar. Hightemperature slow pyrolysis (900-1200°C) produces
biocarbon. The pyrolysis temperature is the dominant
process parameter to control critical properties (e.g.
volatile matter, carbon and fixed carbon contents,
reactivity, surface area, density, tensile/compressive
strength, grindability, etc.). One limitation to
improving biochar/biocarbon properties is thatbiomass carbonization proceeds via a charring
mechanism (no molten phase). The lack of a molten
phase during carbonization limits the capacity toengineer critical material properties. Biochar andbiocarbon have numerous applications including: fuelfor cooking, adsorbents for air/water purification, acarbon sequestering soil amendment, and a carbon
neutral coal/coke replacement in industrial
applications. All are applicable in Hawaiʻi and can beproduced from low value biomass materials.
BACKGROUND: Research at HNEI has identified
certainconstant-volume/pressurized
reactionconditions that result in the formation of biochar withdrastically altered morphology compared to theparent biomass. This unique biochar experiences atransient plastic phase (TPP) during carbonization,
representing a new biomass carbonization pathway.
The underlying mechanisms of TPP formation andutility are still being explored. The current research
effort used parametric research design toindependently study the effects of pressure,temperature, water content, and biomass type on theformation of TPP biochar. In addition to standard
analytical tools (proximate analysis, true density,
ultimate analysis), powder compaction experiments
have been developed to characterize material
plasticity and mechanical strength. Thesefundamental insights have been leveraged to increasebiocarbon mechanical strength, a critical bottleneckfor commercial applications.
PROJECT STATUS/RESULTS: Experimental results
demonstrate that TPP formation proceeds through amolten phase. Elevated pressure serves to keep waterin the condensed phase, inhibiting condensation
reactions and enabling molten phase formation. TPP
formation conditions were identified for a range ofbiomass types including hardwoods, softwoods, andherbaceous materials. Results from powder
compaction experiments show that TPP biochar has
increased plasticity along with a reduced glasstransition temperature. Experiments comparing themechanical strength of TPP and standard biocarbon
materials show the TPP material is 10 times stronger,
and twice as dense. Efforts to maximize themechanical strength of TPP biocarbon achieved
another 10x improvement, the strongest biocarbon
material reported in the scientific literature (Figure 1).
These mechanical properties exceed values required
for numerous industrial applications. This novel
production pathway overcomes technical barriers
limiting biomass utilization as feedstock forbiocarbons that can displace fossil carbon products.
Potential
applications
includemetallurgicalreductants, binders, electrodes, or high value
specialty materials. A preliminary patent application
has been filed to protect this intellectual property andlicensing negotiations are underway.

Figure 1. Biocarbon pellets produced from TPP biochar.

Funding Source: SINTEF Energy Research; Officeof Naval ResearchContact: Scott Turn, sturn@hawaii.edu;
Robert Johnson, robertlj@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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77

Hawaiʻi Natural Energy Institute Research Highlights
Appendix E: Alternative Fuels
E5: Solar Fuels Generation

OBJECTIVE AND SIGNIFICANCE: The objective of
this research is to improve the durability andefficiency of chalcopyrite and perovskite thin-film
photo-absorbers for photoelectrochemical (PEC)
production of solar fuels, aiming for a $1/kg
production cost of renewable hydrogen.

monolithically stacked on top of each other tomaximize STH efficiency. With such architecture, thedeposition process of each layer must not damage thepreviously deposited layers and interfaces in any way.
Our results showed that chalcopyrites are notcompatible with monolithic MJ integration.

BACKGROUND: Sometime referred as Artificial
Photosynthesis, PEC technology combines advanced
photovoltaic (PV) materials and catalysts into a single
device that uses sunlight as the sole source of energy
to split water into molecular hydrogen and oxygen. In
a typical PEC setup, the solar absorber is fully
immersed into an electrolyte solution and solar fuels
are generated directly at its surface. Fuels producedwith this method can be stored, distributed, andfinally recombined in a fuel cell to generate
electricity, with water as the only byproduct.

PROJECT STATUS/RESULTS: In 2023, HNEI andpartners at Stanford, UNLV, LLNL and NREL
received DOE funding to specifically develop a novel
integration scheme in which material classes can be
combined regardless of their nature while preserving
their intrinsic performance. Such a scheme, pioneeredby HNEI and known as semi-monolithic integration,
relies on 2D materials-assisted exfoliation and room
temperature bonding techniques to transfer fully
integrated cells from their original substrates onto
new handles. With this integration scheme, sub-cells
can be successively transferred onto a new host to
create a fully functional MJ structure. By design,semi-monolithic integration allows to circumvent allmaterial incompatibilities, enabling new MJ
architectures otherwise not possible withconventional monolithic integration. With thisintegration scheme, HNEI was able to fabricate theworld’s first chalcopyrite triple junction PEC device
with 3% STH efficiency (proof-of-concept). HNEI
will leverage this new technology to combine
chalcopyrites and perovskites photo-absorbers,
aiming for MJ devices with STH efficiencies of atleast 15%.

Under two consecutive DOE awards received in 2014
and 2017, HNEI partnered with the University of
Nevada, Las Vegas (UNLV), Stanford, the National
Renewable Energy Laboratory (NREL), andLawrence Livermore National Laboratory (LLNL) toestablish a unique tool chest of theoretical modeling,state-of-the-art synthesis, and advanced material andinterface characterization to provide deeper
understanding of PEC materials and engineer highperformance devices. Focusing on the chalcopyrite
material class, our group was able to synthesize solar
absorbers capable of generating photocurrent
densities relevant to high solar-to-hydrogen (STH)
efficiencies (>12%). We also demonstrated thattungsten oxide (WO3) films only few atoms thickcould increase the stability of chalcopyrites in acid bya factor of 2 when compared to un-coated samples.
A key challenge remains: materials integration into
“multi-junction” (MJ) PEC water splitting devices, anintegration scheme in which thin film materials are

To date, this project has produced five peer reviewed
papers, which are listed on the following page.
Funding Source: Department of Energy
Contact: Nicolas Gaillard, ngaillar@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

78ADDITIONAL PROJECT RELATED LINKSPAPERS AND PROCEEDINGS:
1. 2022, K. Outlaw-Spruell, J. Crunk, W. Septina, C.P. Muzzillo, K. Zhu, N. Gaillard, Semi-monolithic
Integration of All-Chalcopyrite Multijunction Solar Conversion Devices via Thin-Film Bonding
and Exfoliation, ACS Applied Materials and Interfaces, Vol. 14, Issue 49, pp. 54607-54615.
2. 2021, N. Gaillard, A perspective on ordered vacancy compound and parent chalcopyrite thin film
absorbers for photoelectrochemical water splitting, Applied Physics Letters, Volume 119, Issue 9,Paper 090501.
3. 2021, I. Khan, C.P. Muzzillo, C.L. Perkins, A. Norman, J. Young, N. Gaillard, A. Zakutayev, MgxZn1-xO
contact to CuGa3Se5 absorber for photovoltaic and photoelectrochemical devices, JPhys Energy, Vol.
3, Issue 2, Paper 024001. (Open Access: PDF)
4. 2021, D.W. Palm, C.P. Muzzillo, M. Ben-Naim, I. Khan, N. Gaillard, T.F. Jaramillo, Tungsten oxidecoated copper gallium selenide sustains long-term solar hydrogen evolution, Sustainable & Energy
Fuels, Vol. 5, Issue 2, pp. 384-390.
5. 2020, A. Sharan, F.P. Sabino, A. Janotti, N. Gaillard, T. Ogitsu, J.B. Varley, Assessing the roles of Cuand Ag-deficient layers in chalcopyrite-based solar cells through first principles calculations,
Journal of Applied Physics, Vol. 127, Paper 065303.

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79

Hawaiʻi Natural Energy Institute Research Highlights

Appendix E: Alternative Fuels
E6: NELHA and MTA Hydrogen Stations and Fuel Cell Electric BusesOBJECTIVE AND SIGNIFICANCE: In 2022, HNEI
commissioned a 65kg/day hydrogen production anddispensing station on the Island of Hawaiʻi at the
Natural Energy Laboratory Hawaiʻi Authority(NELHA) (Figure 1) and demonstrated on-site
fueling of an electric-fuel cell hybrid bus. The overall
objective of the project is to evaluate the technical andfinancial performance and durability of theequipment, and support a fleet of three hydrogen Fuel
Cell Electric Buses (FCEB) operated by the Countyof Hawaiʻi Mass Transit Agency (MTA). The
knowledge gained in this project will inform the
MTA on benefits and issues associated withtransitioning from a diesel bus fleet to a zero
emissions FCEB fleet in support of the County of
Hawaiʻi’s clean transportation goals. The knowledge
will also help inform decisions on other islands.

electric vehicles. HNEI has delivered training to bus
drivers and First Responders.

Figure 2. Concept for hydrogen transport on Hawaʻii
Island.

PROJECT STATUS/RESULTS:
Hydrogen Station: The site infrastructure, as well as
the hydrogen production and compression systems
equipment, have been installed at NELHA (Figure 3).
In 2021, the station was fully commissioned by HNEIand Powertech, the equipment supplier. The first fillof a hydrogen bus for public transportation took placeon March 24, 2022.

Figure 1. HNEI’s NELHA hydrogen station.

BACKGROUND: Development of hydrogen-basedtransportation systems requires infrastructure to
produce, compress, store, and deliver the hydrogen; ameans to dispense the fuel; and vehicles to use thehydrogen. The HNEI hydrogen station at NELHA has
been designed to dispense hydrogen at 350 bar (5,000psi). In place of ground-mounted tank storage, HNEI
will demonstrate centralized hydrogen production
and distributed dispensing with a fleet of threehydrogen transport trailers (HTT). High purity
hydrogen produced at NELHA will be delivered to
the MTA base yard in Hilo to support heavy-duty
FCEBs operated by the MTA Hele-On public bus
service (Figure 2).
In additon to the technical and cost analysis, HNEI isdeveloping implementation plans to support the
introduction of zero emission transportation systems.
HNEI is coordinating with the University of
Hawaiʻi’s Hawaiʻi Community College and theCounty of Hawaiʻi MTA to support the introductionof workforce development programs to traintechnicians to service the FCEBs and other battery

Figure 3. HNEI’s NELHA hydrogen station.

The station uses a Proton Onsite (now Nel)electrolyzer to produce 65 kg of hydrogen per day atan outlet pressure of 30 bar (440) psi. A HydroPak
compressor (Figure 4) compresses the hydrogen to
450 bar (6,600 psi).

Figure 4. HydroPac compressor.

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80

The system is powered by the Hawaiʻi Electric Light
Company (HELCO) grid which includes a substantial
fraction of renewable energy including solar, wind,and geothermal.

to reduce transportation costs by not having to returnhalf-filled trailers to be refilled at NELHA.

Hydrogen Transport Trailers: Three trailers (Figure5) are available for transport between the production
and fueling site and are certified by the Federal
Transit Administration for use on U.S. public roads.
The hydrogen cylinders must be recertified every five
years.

Figure 7. MTA boost compressor fueling post.

Figure 5. Hydrogen transport trailer.

Hydrogen Dispensing System: The dispensing system
consists of a dispenser (Figure 6) connected to afueling trailer through a fueling post interface that isconnected to the dispenser via an undergroundhydrogen piping distribution system. The hydrogendispenser is fully automated and programmed to “failsafe” for unattended operation.

Hele-On 21-Passenger Fuel Cell Electric Bus: The
Hele-On 21-passenger FCEB (Figure 8) was
purchased with funds from the Energy Systems
Development Special Fund. This bus, manufactured
by Eldorado National, and converted to a hydrogenelectric drive train by U.S. Hybrid, is ADAcompliant. Within the last year, the fuel cell powersystem was upgraded by replacing the original 30 kW
Hydrogenics fuel cell with a new state-of-the-art 40
kW U.S. Hybrid fuel cell. During commissioning, thefuel cell produced 46 kW, a 15% improvement, andthe range increased from 200 to 300 miles, a 50%
improvement.

Figure 8. Hele-On 21-passenger FCEB.

Figure 6. Hydrogen station dispenser.

The fueling dispensers located at NELHA and at
MTA are identical except for the addition of a boost
compressor at the MTA site integrated into the MTA
fueling post (Figure 7). The boost compressor system
was developed by HNEI and Powertech to dispense
up to 90% of the hydrogen stored in the HTT in order

Onboard hydrogen is stored in composite carbon fiber
cylinders located under the bus with a capacity of 19kg. The fuel cell power system is integrated with two
11 kWh (total 22 kWh) LG Lithium-ion battery packs
to provide motive power to a 200 kW electric drive
system. U.S. Hybrid replaced the original batteries
with the new technology batteries using their internalfunding. At cruising speed, the fuel cell maintains thebattery state of charge within a range that supports thelong-term health of the battery.
During deceleration, the electric motor acts as a
generator sending power back into the battery

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81

(“regenerative braking”). This contributes to overallsystem energy efficiency and improves bus mileage.
depending on the route topography and driver skills.

single dispenser can support approximately 22 buses(illustrated) over a 6 hour period at a 16 minute
fueling interval.

A 10 kW export power system (Figure 9) was
installed in the 21-passenger bus to enable the bus toprovide 110/220VAC electric power at full power for
up to 30 hours as emergency power for civil defense
resilience operations when the grid power is down.
The bus can be refueled in ~15 minutes providing an
additional 30 hours of emergency power.
Figure 11. Concept design of MTA fueling dispensing
station.

Figure 9. Bus export power unit.

Hele-On 19-Passenger Fuel Cell Electric Buses: Two
19-passenger FCEBs (Figure 10) were acquired by
the MTA from Hawaiʻi Volanoes National Park
(HAVO). These buses were converted by U.S. Hybrid
and are of similar design to the 21-passenger FCEB.
Onboard hydrogen capacity is 10 kg giving a
projected range of 100 miles. These buses are being
upgraded with 90 kW Hyundai fuel cells and one 33
kWh A123 Lithium-ion battery using funding
provided by the County of Hawaiʻi.

Figure 12. Concept of MTA site with fueling dispenser.

Hydrogen Station Energy Consumption: The total
power consumption of the hydrogen system including
the electrolyzer, compressor, and balance of plant is~210 to 240 kW when operating at the maximum
production rate of 65 kg/day (2.7 kg/hr). This
corresponds to approximately 78 to 88 kwh/kg ofcompressed hydrogen. Figure 13 and Table 1
provides the breakdown of the observed power usage.
This represents the largest single load on the NELHA
research campus grid.

Figure 10. HAVO 19-passenger FCEB.

Figure 11 is a conceptual design of the hydrogenfueling dispensing system proposed to be located at
the MTA base yard in Hilo which is comprised of
repurposed, new equipment that was originallyintended to support the two HAVO buses.
HNEI consulted with the MTA to select the location(Figure 12) for the hydrogen dispensing system. This

Figure 13. Observed performance data from the MTA
FCEB.

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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82

Table 1. NELHA Hydrogen Station Observed Power
Usage.

Electrolyzer in pre-start (no otherequipment)
Electrolyzer in standby
Electrolyzer air cooler
Electrolyzer/Compressor room
fans
Compressor Chiller
Electrolyzer filling/verifying
A500 tank (air cooler)
Electrolyzer stack circulation state
w/ air cooler
A500 filling with electrolyzer
room fan/air cooler
Small compressor (only operates
in short bursts)
Full production with fans,compressor, chillers

550

W

740
260

W
W

800

W

800

W

850

W

1.05

kW

1.35

kW

1.5

kW

210-240kWMTA FCEB Performance: The MTA buses are fittedwith sensors and a data acquisition system thatmonitors bus system performance. Data is transmitted
by cell phone telemetry to a remote computer.
Outputs include powertrain energy consumption in
kWh per mile and miles per kg of hydrogen. This data
supports management of the bus fleet including
identifying developing maintenance problems.
FTA Low/No Grant: In 2022, HNEI assisted theCounty of Hawaiʻi MTA in the development of their
proposal resulting in a grant for $14 million from theFederal Transit Administration Low emissions/No
emissions bus program. The funding will support theacquisition of six (6) new fuel cell electric buses andrelated infrastructure. MTA Administrator John
Andoh stated that “the technical assistance of HNEI
helped the MTA win this grant award”.

Figure 14. “Meet the Bus” event on Hawaiʻi Island.

This project has produced the following papers:• 2020, A. Headley, et al., Valuation and cost
reduction of behind-the-meter hydrogenproduction in Hawaiʻi, MRS Energy &Sustainability, Vol. 7, Paper E26.
• 2020, M. Virji, et al., Analyses of hydrogenenergy system as a grid management tool for
the Hawaiian Isles, International Journal of
Hydrogen Energy, Vol. 45, Issue 15, pp. 80528066.
Funding Sources: U.S. Department of Energy; Officeof Naval Research; NELHA; U.S. Hybrid; State of
Hawaiʻi Hydrogen Fund; County of Hawaiʻi; Energy
Systems Development Special FundContact: Mitch Ewan, ewan@hawaii.edu;
Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

Public Outreach: On July 11, 2023, attendees of the“Meet the Bus” event (Figure 14) in West Hawaiʻigathered for a photograph in front of the island’s firstever hybrid hydrogen electric bus. Hawaiʻi County
Mayor Mitch Roth said, “look at what comes out ofthe vehicle – you don’t see smog; you just see watercoming out. We’ve been looking at ways to havegreen energy, and hydrogen looks like the way of the
future.”Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

83

Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F1: Contaminant Tolerant Fuel Cells for Harsh Environments

OBJECTIVE AND SIGNIFICANCE: Fuel cells offer theopportunity to significantly increase the flight
duration of electric powered unmanned aerial
vehicles (UAVs). With fuel cell power systems,
increases of 5-10x in flight duration are possible forthe same volume and weight constraints as highenergy lithium batteries. Under this task, HNEI
continued support to the Naval ResearchLaboratory’s (NRL) efforts to develop lightweight,
high efficiency fuel cell systems for UAVs including
developing components that enhance contaminant
tolerance. Contamination mechanisms in proton
exchange membrane (PEM) fuel cells can become
quite complex with many sources (air, fuel, system
materials) and problems can be compounded by thecontaminant reaction products that impact many key
fuel cell materials.
BACKGROUND: A partnership between HNEI and
NRL was established in 2009 to aid in NRL’s
development of the IonTiger UAV using a fuel cellmade by an outside vendor. This NRL program
resulted in an unofficial world-record fuel cell
powered UAV flight of 26 hours on compressedhydrogen, and later 48 hours using an NRLdeveloped, cryogenic hydrogen storage system.
Subsequently, NRL has continued to develop theirown proprietary fuel cells and systems for UAV
applications. HNEI has supported this effort, andcontinues to support this effort, via diagnostic testing,evaluation of needs, and design recommendations.
More recently, HNEI has shifted focus from testingsupport and is currently working on the design,development, and demonstration of PEM fuel cellcomponents that enhance contaminant tolerance atelevated operating temperatures. Most industry wide
efforts in contamination to date have primarily
focused on low temperature (60-90°C) PEM fuel cells
for transportation and unmanned vehicle applications.
High temperature (140-200°C) PEM (HT-PEM) fuelcells have the benefits of higher contaminant
tolerance and lower cost membranes vs. low
temperature PEM fuel cells. Additionally, the higher
operating temperatures can help reduce the systemcomplexity and provide opportunities for volume
reduction, e.g. heat exchanger size reduction, a major
consideration for use of fuel cells for small UAVs (110 kW).

Under this work, HNEI is establishing a fabrication
system (Figure 1) developed by NRL for creating
custom catalyst coated membranes for small UAV
scale fuel cells based on ultrasonic spray deposition
and is adapting the NRL protocol to work with hightemperature materials with inherent contamination
resistance. The ability to create custom catalyst
coated membranes (CCMs) is an essential capability
in the research and development of advanced
electrocatalysts, gas diffusion media (GDM),
ionomers, polymer electrolyte membranes, andelectrode structures designed for use in nextgeneration contaminant resistant fuel cells for UAVs.

Figure 1. Ultrasonic spray coating system for in-housemanufacturing of custom CCMs.

PROJECT STATUS/RESULTS: To date, we have
performed literature review and identified optimal
electrode structure of HNEI’s first generation HTPEM membrane electrode assembly using readily
available materials and began developing andevaluating fabrication protocols. Researchers alsoestablished collaborations with producers of the next
generation of materials for high temperature fuel cells
and began development of HNEI’s 2nd generation
HT-PEM membrane electrode assembly.
Funding Source: Office of Naval ResearchContact: Keith Bethune, bethune@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

84ADDITIONAL PROJECT RELATED LINKSPAPERS AND PROCEEDINGS:
1. 2020, K. Bethune, J. St-Pierre, J.M. LaManna, D.S. Hussey, and D.L. Jacobson, Contamination
Mechanisms of Proton Exchange Membrane Fuel Cells-Mass Transfer Overpotential
Origin, The Journal of Physical Chemistry C, Vol.124, Issue 44, pp. 24052-24065.
2. 2020, Y. Garsany, C.H. Bancroft, R.W. Atkinson III, K. Bethune, B.D. Gould, K.E. SwiderLyons, Effect of GDM Pairing on PEMFC Performance in Flow-Through and Dead-Ended
Anode Mode, Molecules, Vol. 25, Issue 6, Paper 1469. (Open Access: PDF)
3. 2015, B.D. Gould, J.A. Rodgers, M. Schuette, K. Bethune, S. Louis, R. Rocheleau, K. SwiderLyons, Performance and Limitations of 3D-Printed Bipolar Plates in Fuel Cells, ECS
Journal of Solid State Science and Technology, Vol. 4, Issue 4, pp. P3063-P3068. (Open Access:
PDF)
PRESENTATIONS:
1. 2022, Y. Garsany, R. E. Carter, M.B. Sassin, K. Bethune, and B. Gould, Pairing Gas Diffusion
Media for High-Power PEMFC Operation, Presented at the ECS 2022-02 Meeting, Atlanta,
Georgia, October 9-13, Abstract 1380.
2. 2020, Y. Garsany, C.H. Bancroft, R.W. Atkinson, K. Bethune, B.D. Gould, K. Swider-Lyons,Operation of PEMFC Anodes in Dead-Ended Vs. Flow-through Modes, Presented at the
ECS 2020-02 Meeting, Honolulu, Hawaiʻi, October 4-9, Abstract 2212.
3. 2019, Y. Garsany, R.W. Atkinson, K. Bethune, J. St-Pierre, B.D. Gould, K. Swider-Lyons,
Cathode Catalyst Layer Design with Graded Porous Structure for Proton Exchange
Membrane Fuel Cells, Presented at the ECS 2019-02 Meeting, Atlanta, Georgia, October 1317, Abstract 1423.

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85

Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F2: Anion Exchange Membrane Fuel CellOBJECTIVE AND SIGNIFICANCE: Interest inanion exchange membrane fuel cells (AEMFCs)
is driven by the potential for lower cost andincreased durability. The goals of this project areto 1) evaluate the performance of AEMFCs withplatinum group metal (PGM) content and PGMfree cathode catalysts under various operating
conditions, 2) study effects of membraneelectrode assemblies (MEAs) components on
mass transport, water management, anddurability, and 3) develop electrochemical
diagnostic and analysis methods applicable for
AEMFC evaluation.
BACKGROUND: Interest in AEMFCs technology(Figure 1) has been driven by possible
substitution of Pt electrocatalysts by platinum
metal group (PGM)-free materials, since theirperformance in hydrogen oxidation and oxygen
reduction in alkaline media is comparable oreven higher than Pt. Moreover, operation in an
alkaline environment is less corrosive and can
improve durability.

The main approach to improve AEMFC
performance and durability is a design of catalyst
layers with optimal porosity, hydroxide ion
conductivity and thickness to insure developmentof three phase boundaries, and sufficient reagents
transport, as well as adequate choice of gas
diffusion layers (GDLs) for better water
management. In addition, there is a lack ofharmonized testing protocols and procedures anddevelopment of electrochemical diagnostics andapproaches are critical for AEMFC.
PROJECT STATUS/RESULTS: Under this effort,
HNEI has reached the following results:• Established a capability to produce small size
catalyst coated membranes and catalyst
coated substrates, which gives opportunity
for rapid evaluation of novel emerging
materials available in the limited quantities;• Established a break-in/start-up procedure
after discussion with AEM manufactures andsuccessfully tested;• Identified critical parameters for Pt-based
AEMFC MEAs, i.e., ionomer content andcatalyst loading in anode and cathode; and• Several pretreatment procedures of catalyst
coated membranes were evaluated and the
optimal pretreatment was identified.
Future work will include a continuation ofelectrochemical studies of AEMFCs with focus
on MEAs reproducibility, durability, andperformance.
Funding Source: Office of Naval Research

Figure 1. Schematic representation of AEMFC.

Design of MEAs for alkaline fuel cells is still in
its infancy. Moreover, operation of AEMFC
requires O2 and water at the cathode, while waterproduction happens at the anode; the situation iscompletely opposite compared to PEMFCs,
which brings additional complexity andrequirements to the MEA structure.

Contact: Tatyana Reshetenko,
tatyanar@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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86

Hawaiʻi Natural Energy Institute Research Highlights

Appendix F: Electrochemical Power Systems
F3: Transition Metal Carbide Catalysts for Electrochemical Applications
OBJECTIVE AND SIGNIFICANCE: The objective of
this project is to develop transition metal carbide
catalysts for electrochemical applications. These
carbide catalysts have the potential to improve theperformance of a variety of electrochemical devices
including fuel cells, water electrolyzers, andvanadium redox flow batteries.
BACKGROUND: The commercial application of anumber of electrochemical technologies would
benefit from the availability of low cost, efficient, anddurable catalysts. Pt-group-metal catalysts are used inmost commercially available fuel cells and waterelectrolyzers. Unfortunately, they have the shortcomings of high cost, low earth abundance, andlimited lifetime. Transition metal carbides are
attractive candidates because they possess anelectronic structure similar to Pt – which promotes
high activities, good electrical conductivity, low cost,high abundance, and outstanding thermal andchemical stabilities. However, carbide synthesis is achallenge for achieving high surface area particles
due to the inevitable aggregation during the hightemperature carburization.

x)2O3, V8C7, as well as some unreacted TiC. VxTiC

exhibited excellent electrochemical stability up to 1.4
V (Figure 2) and better catalytic activity towardhydrogen evolution reaction (HER) than VxC (Figure3). Both VxC and VxTiC showed increased HER
catalytic activity after up to 1.4V cycling.
Further electrochemical tests will be performed using
carbides incorporated on carbon substrate as theworking electrode. SEM/EDS will be used formorphological and elemental analysis. TEM will be
used to investigate particle size and structure.

Figure 2. Cyclic voltammograms at 100mV s−1 in N2saturated 0.5M H2SO4 at 25°C.

Figure 1. X-ray diffraction patterns.

PROJECT STATUS/RESULTS: This work is exploringa simple and environmentally friendly synthesis
process for carbides that involve in situ carburizationof a metal precursor and a carbon material.
Considering the excellent electrochemical stability of
TiC, the commercially available TiC was chosen as
the carbon source and support to increase the stabilityof vanadium carbide. By modifying the synthesis andtreatment approaches, VxTiC was synthesized. As
shown in Figure 1, VxTiC contains Ti-V oxide (TixV1-

Figure 3. Polarization curves with a rotation rate of
1600rpm at 2mV s−1 in N2-saturated 0.5M H2SO4 at
25°C.

Funding Source: Office of Naval ResearchContact: Jing Qi, qijing@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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87

Hawaiʻi Natural Energy Institute Research Highlights

Appendix F: Electrochemical Power Systems
F4: Materials Enablers for Advanced Manufacturing of Attritable Fuel Cells
OBJECTIVE AND SIGNIFICANCE: Hydrogen fuel cellsystems are ideally suited to power small unmannedsystems that will be increasingly important whencompeting against near-peer adversaries, especiallyfor isolated forces in the INDOPACOM region. A key
facet of small unmanned systems is their attritability
relative to expensive weapons systems. Attritable fuelcell powered unmanned systems require that the costof fuel cells decrease so that their loss is acceptable inan exchange. This cost decrease can be traded against
durability and performance, but ideally, both
performance and durability would remain relatively
constant. This is a uniquely DoD problem whosematerials challenges are not being addressed by thebroader fuel cell industry or academia.

cells (HT-PEM) to develop materials enablers thatwill allow for the construction fuel cells with cheaper
assembly costs through a simpler system architecture
to reduce components. HT-PEM also has the potential
to reduce the costs of precious metal catalysts andpolymer membrane substrates to achieve the target
cost reduction. The higher operating temperatures of
HT-PEM directly addresses heat rejection challenges
through higher temperature operation (120-200°C).
Volumetric storage challenges of hydrogen are
indirectly addressed in this project through a simpler
fuel cell system architecture and increased heatrejection that leads to volume savings in the fuel cellsystem that can be applied to hydrogen storage spaceclaim.

The objective of this project is to perform material
research combined with simulation to propose aconceptual design for a fuel cell with laminate
construction to realize a 5x cost decrease over stateof-the art (SOA) small fuel cells (0.5-5 kW) while
retaining performance.
BACKGROUND: Hydrogen fuel cells have the ability
to store energy efficiently, produce electric powerwith low signature, and operate with minimum
maintenance providing an important compliment tobattery electric systems and internal combustion
engines. Key advantages over the incumbent
technologies are 4-8x gravimetric energy storage
density over batteries, which translates into 4-8x
endurance/range for systems and low signature DC
power with improved start times over internal
combustion engines. Key technical challenges remain
for hydrogen fuel cells, namely cost, heat rejection,and volumetric storage density of hydrogen ascompared to logistic fuels.
A large fraction of cost of system fabrication forsmall-scale fuel cells is associated with the bipolar
plates and the labor costs associated with building thedevice because of the large part count. The objectiveof this work is to move fuel cell manufacturing closer
to battery manufacturing, in which continuous reelto-reel process are used to manufacture the electrode,which are then rolled or stacked into containers that
require very little handwork or parts registration.

Figure 1. a) Traditional fuel cell stack with bipolar plateinterconnects, b) previous demonstrated “Stackless FuelCell” by ONR, c) concept for a closed-cathode air-cooled
fuel cell that would be attritable.

PROJECT STATUS/RESULTS: To date, we havedown-selected components and fabrication protocols
that yield peak power representative of the current art
and began evaluating electrode fabrication
techniques. Researchers have also designed andproduced current collectors based on flexible circuitboard technology and began planning fordemonstrating operation with OEM and HNEI
produced electrodes in a single cell. The year 1 results
Investigating the Suitability of Printed Circuit
Components for Fuel Cells were presented at the244th Electrochemical Society meeting in October
2023.
Funding Source: Office of Naval ResearchContact: Keith Bethune, bethune@hawaii.edu
Last Updated: November 2023

Under this work, HNEI is investigating the potentialof high temperature proton exchange membrane fuelHawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

88Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F5: Proton Conducting Electrolytes for HT-PEMFCOBJECTIVE AND SIGNIFICANCE: The objective of
this project is to develop a novel inorganic electrolytewith high proton conductivity under high temperatureand low humidity to be used in the cathode catalyst
layer of high temperature proton exchange membrane
fuel cell (HT-PEMFC) to overcome the phosphoricacid (H3PO4) leaching issue. Operation of PEMFCs at
HT would facilitate meeting U.S. Department ofEnergy’s (DOE) technical targets for performance,
power and energy density, cost, and liability byinhibiting the poisoning effects of air pollutants andfuel impurities and simplifying the system’s waterand heat management.
BACKGROUND: PEMFCs are considered a promisingclean energy technology for transportation andstationary applications. Contaminants in air andhydrogen fuel are a major challenge for the Pt
catalysts in a typical PEMFC when it is operated in
the realistic atmosphere. HT operation (150-200°C)
of PEMFCs has been considered as one of thepotential solutions to mitigate the poisoning effects
due to the high conversion rate or weak adsorption of
the contaminants. HT operation also facilitates theheat transport and the mass transfer of oxygen andhydrogen because the large temperature difference
and the absence of liquid water in the cell,respectively. With those advantages, HT-PEMFCs
would eliminate the humidifier and simplify the airand fuel supply and the cooling system. However, thecurrent perfluorosulfonic acid (PFSA, Nafion®)polymer electrolytes are limited application below
90°C. The high temperature polymer PBI doped with
H3PO4 (H3PO4/PBI) has been used as the PEM andthe electrolyte in the catalyst layer of HT-PEMFC.
However, H3PO4 leaching is a major issue during
operation, especially from the cathode catalyst layer.
Recently, layered inorganic materials with “water insolid” have been developed as proton conducting
electrolytes for the proton battery. The hydrogenbond switching among the ligand water provides afast proton transport network in mutilayer structures(Figure 1). The proton conducting materals can also
be used in the catalyst layers of the HT-PEMFC.
PROJECT STATUS/RESULTS: At HNEI, novel
inorganic layered structure materils are being
developed as proton conducting electrolyte. The
candidate will be integrated into the in the cathode of

HT membrane electrode assemblies (MEAs) of thecontaminant tolerant FCs for harsh environments.

Figure 1. H-bond network in the layered structures of the
inorganic proton conducting materials.

Currently, the proton conducting electrolyte powders(Figure 2a) were obtained by a fluxing method. The
production yield was improved from ~5% to ~50% by
optimizing the conditions of synthesis. With thepreliminary tests, the electrolyte powder pellet(Figure 2b and 2c) shows a bulk proton conductivityof ~10-3 Scm-1 and a particles boundary conductivityof ~10-5 Scm-1 in the range of from room temperature
to 150°C (Figure 3). The conductivity increases withthe rise of temperature.
A

B

C

Figure 2. The pictures of the proton conductor powders(A) and the pellet (B, C). and the SEM images of thepowders (D) and the cross-section of the pellet (E, F).

Additionally, with collaboration of industrial andacademic partners, a proposal titled with “High
Performing and Durable MEAs with Novel Electrode
Structures and Hydrocarbon Proton Exchange
Membranes” was submitted to the U.S. DOE for
addressing: Hydrogen and Fuel Cell Technologies

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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89Office FOA in Support of Hydrogen Shot (DE-FOA0002920), Topic Area 4: High Performing and
Durable Membrane Electrode Assemblies for
Medium- and Heavy-Duty Applications. The
proposed research was selected for a $4M award in
three years.

Figure 3. The bulk and boundary proton conductivity ofthe proton conducting particles at temperature 20-150°C.

In the future, HNEI plans to characterize the materials
structures, composition and stability. The properties
and performance of the materials will be further
studied and improved with the optimization thesynthesis procedures. The selected materials will be
integrated into the cathode catalyst layers of HTMEAs. The performance of HT-PEMFC with new
proton conductive materials will also be evaluated at150-200°C.
Funding Source: Office of Naval ResearchContact: Yunfeng Zhai, yunfeng@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

90Hawaiʻi Natural Energy Institute Research Highlights

Appendix F: Electrochemical Power Systems
F6: Advanced Characterization of PEMFC with Open Flow Field Architecture
OBJECTIVE AND SIGNIFICANCE: Proton exchange
membrane fuel cells (PEMFCs) are energy
conversion devices that offer high power densities
at low operating temperatures making PEMFCs themost promising technology for many applications,such as automobiles, back-up power generating
units, and portable devices. Commercial PEMFC
systems utilize open flow field (OFF) architectures
ensuring high power generation and excellent
performance at high currents. The project objective
is to conduct a detailed evaluation of PEMFCs
employing OFF design using advanced approaches
like electrochemical impedance spectroscopy (EIS)and segmented cell system.
BACKGROUND: Application of a conventional landchannel flow field architecture for PEMFC results
in non-uniform performance over the active area ofmembrane electrode assembly (MEA) due toincremental O2 consumption from air stream, waterproduction and accumulation. These results lead tohigher performance of the inlet of the fuel cell andlower performance at the outlet. In order to address
this nonhomogeneous performance, open flow
field architecture is applied for commercial
PEMFCs (Figure 1). The main benefits of metal
based OFF are its high durability and costeffectiveness. Moreover, OFF increases utilizationof MEA geometrical area.

responses from 10 segments simultaneously andprovide valuable information on local performance(Figure 2).
Current
Sensing

PXI

Sensors

DAQ

Load
Box

SingleCell
Test
StationSegm. Cell

Figure 2. Schematic of segmented cell system.

PROJECT STATUS/RESULTS: Under this effort,
HNEI has reached the following results:• Demonstrated feasibility of incorporation of
the OFF to HNEI’s segmented cell system;• OFF ensured uniform performance over MEA
compared to the conventional land-channel
flow field architecture;• OFF demonstrated superior performance thanthe land-cannel flow field especially in highpower generating conditions; and• OFF ensures better heat transfer anddissipation, which is important for operation athigh current.
Future work will include a continuation of studies
of PEMFCs with the OFF.
Funding Source: Nuvera Fuel Cells
Contact: Tatyana Reshetenko,
tatyanar@hawaii.edu
Last Updated: November 2023

Figure 1. Schematic representation of fuel cell with
open flow field.

Previously, HNEI developed a segmented cellsystem to study non-uniform phenomena in aworking fuel cell. The segmented cell systemallows us to record current/voltage/impedance
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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91

Hawaiʻi Natural Energy Institute Research Highlights

Appendix F: Electrochemical Power Systems
F7: Proton Exchange Membrane Fuel Cell Producing Hydrogen Peroxide
OBJECTIVE AND SIGNIFICANCE: Hydrogen peroxide
is widely useful to many industries, as well as themilitary, as an environmentally friendly disinfectant
and liquid oxidant for air-independent fuel cellapplications. The main method for hydrogen peroxide
production today: an anthraquinone-oxidation
process, is energy-intensive, expensive, produces
waste that negatively impacts the environment, and is
not easily scalable, leading to the transport of dilute
solutions at high cost to minimize safety concerns.
The objective of this project is modify a proton
exchange membrane fuel cell (PEMFC) to develop analternative, electrochemical method for synthesizinghydrogen peroxide that also produces energy,
eliminates waste by producing aqueous solutions ofvaried hydrogen peroxide concentrations, and isscalable to address the specific needs of these various
industries and communities.
BACKGROUND: Hydrogen peroxide is consideredamong the world’s top 100 most important chemicals
as it is very versatile and is mainly an eco-friendly
disinfectant. Today, over 95% of hydrogen peroxide
is produced from an anthraquinone-oxidation
process. This process is very costly, mainly due to thefact that it can only economically work at large-scale.
Further, it is a batch process that requires further
separation and dilution processes, which also
necessitate enormous amounts of energy to conduct.
These dilution processes are vital as a safety measure
to transport hydrogen peroxide over a range of
distances due to its explosive nature as an oxidant.
The substantial risks associated with thetransportation of hydrogen peroxide alone produces amajor need for scalable, onsite production of thischemical. If successful, onsite production ofhydrogen peroxide would also provide the means for
wastewater treatment in rural communities.
Hydrogenperoxidecanbesynthesized
electrochemically from hydrogen and oxygen in afuel cell utilizing the 2-electron (e−) pathway of theoxygen reduction reaction (ORR) (Equation 1). Most
polymer electrolyte (PEM) fuel cell research involves
the 4e− pathway of the ORR, or complete reduction ofoxygen which produces water and power (Equation
2).
O2 + 2H+ + 2e− → H2O2 (Equation 1)O2 + 4H+ + 4e− → 2H2O (Equation 2)

Figure 1. 2e− and 4e− pathways for the ORR.

PROJECT STATUS/RESULTS: The experimental planand detailed procedures developed for a selective
catalyst for the 2e− pathway (further referred to as the“nano-dispersed supported-catalyst” or NDSC) was
implemented and verified experimentally in a rotating
ring/disk electrode (RRDE) setup. Results haveshown that the modified NDSC is stable for aminimum of 22 hours under harsh experimental
conditions.
Polarization curves were measured for both the ringand disk currents produced during experimentation
with the NDSC. Hydrogen peroxide and water are
generated at the disk whereas hydrogen peroxide isselectively detected at the ring. Ring current data
versus time and disk potential from both theunmodified and modified NDSC are presented in
Figure 2.

Figure 2. Ring current versus time and disk potential(0.05-0.4V vs RHE) for unmodified and modified NDSC
indicating a significant increase at low disk-potentials(peak region).

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92

The larger peak produced in the ring current for themodified NDSC (red) compared to that of theunmodified NDSC (black) at a low disk-potential(0.05V vs. the Reversible Hydrogen Electrode(RHE)) indicates that the catalyst modification isbeneficial with an increase exceeding 100%. It isnoted that the ring signal indirectly shows thepresence of hydrogen peroxide at the ring electrode.
Preliminary hydrogen peroxide detection tests bycolorimetry were performed to directly confirm thepresence of hydrogen peroxide produced at the disk.
Figure 3 shows the result of a colorimetric test, which
confirmed the presence of approximately 3 mg/Lhydrogen peroxide within the bulk solution after
completion of experimental procedures.

and minimize peroxide decomposition within the cell.
Other performance metrics will also be monitored
during these tests, including exhaust composition andcell power for optimization of hydrogen peroxide
production and electrical power.
Funding Source: Office of Naval ResearchContact: Alexandra Fernandez, af41@hawaii.edu
Last Updated: November 2023

Figure 3. Colorimetric test strip indicating the positive
detection of hydrogen peroxide after insertion into thebulk solution (post-production test).

HNEI is developing a quantitative potentiometrictitration technique for a more precise detection ofhydrogen peroxide in the bulk solution after
experimentation with modified NDSCs. HNEI willcomplete long-term RRDE experiments under a rangeof conditions aimed at maximizing the hydrogen
peroxide yield and characterizing catalyst stability.
Finally, experiments will be conducted in a single, 50
cm2 PEMFC specifically modified (includingchanges in both operating conditions and hardware
design) to simultaneously maximize peroxide yield
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93

Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F8: Path Dependence of Battery Degradation

OBJECTIVE AND SIGNIFICANCE: The objective of
this project is to characterize the impact of different
stresses on the durability of Li-ion batteries usinglarge experimental campaigns and design ofexperiments. Studies could address, among others,
the impact of fast charging and grid-vehicle
interactions on the performance of batteries forelectric transportation. The knowledge gained in thisproject informs best practices to successful battery
durability, safety, fast charging, or vehicle-to-X
integration.
BACKGROUND: Electrification of transportation andgrid-storage are crucial to combat climate change.
Understanding and mitigating battery degradation is
key to improving durability of electric transportationand the reliability of power grids. Complexity stems
from the fact that battery degradation is pathdependent. This implies that usage affects not only
the degradation pace, but also the type of degradation
the batteries experience. Lithium-ion batteries are
known to degrade slowly at first before a rapid
acceleration of which starting time will depend on themix of degradation mechanisms and thus on how thebattery was used. To maximize the utility of large
battery systems, it is essential to understand theimpact of all the stress factors associated with anapplication and their combined effects.
PROJECT STATUS/RESULTS: Our study alreadyshowed that a simplistic approach to V2G, namelythat an EV is discharged at constant power for 1 hour
without consideration of battery degradation, is not
economically viable because of the impact additional

V2G cycling has on battery life. However, we showedthat if the batteries are to be used for frequency
regulation, there is a much lesser impact. We also
showed that, with good battery prognostic models andfurther advances in understanding the causes,
mechanisms, and impacts of battery degradation, asmart control algorithm could take all these aspects inconsideration and make V2G and fast charging areality. It must be noted that, because of pathdependence, different usages might lead to different
results and thus that our results should not yet be
generalized on cells different than the one tested.
Current work with DSTG (Australia) involves anexperimental campaign of more than 700 cells tested
under a HNEI defined design of experiments topredict the degradation of MW systems and maximize
durability and reliability in the field. Collaborative
work is also ongoing with Sandia National
Laboratories and Aalborg University (Denmark).
Research conducted for this project is completed in
the PakaLi Battery Laboratory. This project isongoing and has led to 11 publications, which arelisted on the following page.
Funding Source: Office of Naval Research; Defence
Science and Technology Group (Australia)
Contact: Matthieu Dubarry, matthieu@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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94ADDITIONAL PROJECT RELATED LINKSPAPERS AND PROCEEDINGS:
1. 2022, P.M. Attia, et al., Review—”Knees” in Lithium-Ion Battery Aging Trajectories, Journal of The
Electrochemical Society, Vol. 169, Issue 6, Paper 060517. (Open Access: PDF)
2. 2021, D. Beck, et al., Inhomogeneities and Cell-to-Cell Variations in Lithium-Ion Batteries, aReview, Energies, Vol. 14, Issue 11, Paper 3276. (Open Access: PDF)
3. 2020, M. Elliott, et al., Degradation of electric vehicle lithium-ion batteries in electricity grid
services, Journal of Energy Storage, Vol. 32, Paper 101873.
4. 2020, G. Baure, et al., Durability and Reliability of EV Batteries under Electric Utility Grid
Operations: Impact of Frequency Regulation Usage on Cell Degradation, Energies, Vol. 13, Issue 10,
Paper 2494. (Open Access: PDF)
5. 2019, G. Baure, et al., Synthetic vs. Real Driving Cycles: A Comparison of Electric Vehicle Battery
Degradation, Batteries, Vol. 5, Issue 2, Paper 42. (Open Access: PDF)
6. 2018, M. Dubarry, et al., Durability and Reliability of EV Batteries under Electric Utility Grid
Operations: Path Dependence of Battery Degradation, Journal of the Electrochemical Society, Vol.
165, Issue 5, pp. A773-A783. (Open Access: PDF)
7. 2018, K. Uddin, et al., The viability of vehicle-to-grid operations from a battery technology andpolicy perspective, Energy Policy, Vol. 113, pp. 342-347. (Open Access: PDF)
8. 2017, M. Dubarry, et al., Durability and Reliability of Electric Vehicle Batteries Under Electric
Utility Grid Operations: Bidirectional Charging Impact Analysis, Journal of Power Sources, Vol.
358, pp. 39-49.
9. 2017, D. Ansean, et al., Operando lithium plating quantification and early detection of a commercial
LiFePO4 cell cycled under dynamic driving schedule, Journal of Power Sources, Vol. 356, pp. 36-46.
10. 2016, A. Devie, et al., Durability and reliability of electric vehicle batteries under electric utility grid
operations. Part 1: Cell-to-cell variations and preliminary testing, Batteries, Vol. 2, Issue 3, paper 28.
11. 2016, D. Ansean, et al., Fast charging technique for high power LiFePO4 batteries: a mechanistic
analysis of aging, Journal of Power Sources, Vol. 321, pp. 201-209.

PRESENTATIONS:
1. 2022, R. Wittman, et al., Path Dependence of Li-Ion Battery Degradation During Cycling to 80%
Capacity, Presented at the Material Research Society Spring Meeting, May 8-13.
2. 2021, R. Wittman, et al., Characterizing Materials and Electrochemical Changes in a Range of 18650
Li-Ion Cells Cycled to 80% Initial Capacity, Presented at the 239th ECS Meeting, Chicago, IL, May 30June 3.
3. 2019, M. Dubarry, et al., Synthetic vs. Real Driving Cycles: A Comparison of EV Battery
Degradation, Presented at the 236th ECS Meeting, Atlanta, Georgia, October 13-17.
4. 2019, G. Baure, et al., A Diagnostic and Prognostic Study of the Impact of Electric Utility Grid
Operations on EV Batteries, Presented at the International Coalition for Energy Storage and Innovation
Meeting, Waikoloa, Hawaiʻi, January 5-10.
5. 2017, A. Devie, et al., Durability and Reliability of EV Batteries under Electric Utility Grid
Operations, Presented at the 232nd ECS Meeting, National Harbor, Maryland, October 1-5.
6. 2016, M. Dubarry, et al., Path Dependence in Lithium-Ion Batteries Degradation, Presented at the
ECS PRiME Meeting, Honolulu, Hawaiʻi, October 2-7.
7. 2016, M. Dubarry, et al., EV Cell Degradation under Electric Utility Grid Operations, Presented at
the Next-Generation Energy Storage Conference, San Diego, California, April 18-19.
8. 2015, M. Dubarry, et al., Experimental diagnostic of Li-ion commercial cells, case studies, Presented
at the 225th ECS Meeting, Orlando, Florida, May 11-15.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

95

Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F9: Battery Intelligence: Diagnosis and Prognosis

OBJECTIVE AND SIGNIFICANCE: This project aims
at the development of approaches, tools, andprotocols to improve batteries diagnosis andprognosis via non-invasive in-operando techniques.
BACKGROUND: Battery diagnosis and prognosis is adifficult task. Lithium-ion batteries (LiB) are much
more complex than traditional batteries and theirdegradation is path dependent as different usages(current, temperature, SOC range, SOC window, etc.)
will lead to different type of degradation. In addition,
since large battery packs are composed of thousandsof cells, the use of complex models or a multitude ofsensors for each cell is precluded.
Traditionally, battery diagnosis is handled via two
opposite approaches. The academic route aims for
maximum accuracy and achieves it by inputting a lotof resources. The second route – the one usually usedon deployed systems – uses as little resources as
possible and must not be destructive. As a result, it isineffective in predicting the true state of health.
This assessment of state of the art led HNEI to define
and develop a third industry-compatible intermediateroute to reach an accurate diagnosis with costeffective and non-destructive methods, using only
sensors already available in battery packs while
requiring limiting computing power.
HNEI developed a mechanistic modeling framework
where a battery digital twin is built from individual
electrode data and where the battery degradation isemulated by the scaling or the translation of one
electrode versus the other. Using this framework, thevoltage variations associated with the degradation
mechanisms can be predicted.
Machine learning and artificial intelligence are also
starting to play a crucial role in diagnosing andprognosing batteries. However, their accuracy islimited by the little to no training data available tovalidate algorithms. To solve this issue, HNEI applied
the mechanistic modeling approach to develop thefirst synthetic training datasets. Recent work
highlighted the possible opportunistic diagnosis ofbattery usage for photovoltaic-connected batteries
using models trained and validated on synthetic
datasets.
Research conducted for this project is completed in
the PakaLi Battery Laboratory.
PROJECT STATUS/RESULTS: This project iscurrently ongoing with three industrial collaborations
on different aspects of the problem. A full suite ofsoftware and models were developed. The mainmodel has been licensed by more than 125
organizations worldwide.
This work has also led to 45 publications, many ofwhich are linked on the following pages, and one
patent.
Funding Source: Office of Naval Research; SAFT
(France); Element Energy; ACCURE (Germany)
Contact: Matthieu Dubarry, matthieu@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

96ADDITIONAL PROJECT RELATED LINKSPAPERS AND PROCEEDINGS:
Battery Testing
1. 2022, M. Dubarry, et al., Best practices for incremental capacity analysis, Frontiers in Energy
Research, 10:1023555. (Open Access: PDF)
2. 2022, L. Ward, et al., Principles of the Battery Data Genome, Joule, Vol. 6, Issue 10, pp. 2253-2271.
(Open Access: PDF)
3. 2022, N. Costa, et al., Li-ion battery degradation modes diagnosis via Convolutional Neural
Networks, Journal of Energy Storage, Vol. 55, Part C, Paper 105558. (Open Access: PDF)
4. 2022, P.M. Attia, et al., Review—”Knees” in Lithium-Ion Battery Aging Trajectories, Journal of The
Electrochemical Society, Vol. 169, Issue 6, Paper 060517. (Open Access: PDF)
5. 2021, M. Dubarry, et al., Analysis of Synthetic Voltage vs. Capacity Datasets for Big Data Li-ion
Diagnosis and Prognosis, Energies, Vol. 14, Issue 9, Paper 2371. (Open Access: PDF)
6. 2020, M. Dubarry, et al., Big data training data for artificial intelligence-based Li-ion diagnosis andprognosis, Journal of Power Sources, Vol. 479, Paper 228806.
7. 2020, D. Anseán, et al., Mechanistic investigation of silicon-graphite/LiNi0.8Mn0.1Co0.1O2 commercial
cells for non-intrusive diagnosis and prognosis, Journal of Power Sources, Vol. 459, Paper 227882.
8. 2020, M. Dubarry, et al., Perspective on Commercial Li-ion Battery Testing, Best Practices for
Simple and Effective Protocols, Electronics, Vol. 9, Issue 1, Paper 152. (Open Access: PDF)
9. 2019, A. Barai, et al., A comparison of methodologies for the non-invasive characterisation ofcommercial Li-ion cells, Progress in Energy and Combust. Sci., Vol. 72, pp. 1-32. (Open Access: PDF)
10. 2018, M. Dubarry, et al., Calendar aging of commercial Li-ion cells of different chemistries – A
review, Current Opinion in Electrochemistry, Vol. 9, pp. 106-113.
11. 2018, A. Devie, et al., Intrinsic Variability in the Degradation of a Batch of Commercial 18650
Lithium-Ion Cells, Energies, Vol. 11, Issue 5, Paper 1031. (Open Access: PDF)
12. 2018, C.T. Love, et al., Lithium-Ion Cell Fault Detection by Single-Point Impedance Diagnostic andDegradation Mechanism Validation for Series-Wired Batteries Cycled at 0 °C, Energies, Vol. 11,
Issue 4, Paper 834. (Open Access: PDF)
13. 2017, D. Ansean, et al., Operando lithium plating quantification and early detection of a commercial
LiFePO4 cell cycled under dynamic driving schedule, Journal of Power Sources, Vol. 356, pp. 36-46.
14. 2016, D. Ansean, et al., Fast charging technique for high power LiFePO4 batteries: a mechanistic
analysis of aging, Journal of Power Sources, Vol. 321, pp. 201-209.

Battery Modeling
1. 2023, M. Dubarry, et al., Data-Driven Diagnosis of PV-Connected Batteries: Analysis of Two Yearsof Observed Irradiance, Batteries, Vol. 9, Issue 8, Paper 395. (Open Access: PDF)
2. 2023, M. Dubarry, et al., Accurate LLI and LAMPE Estimation Using the Mechanistic ModelingApproach with Layered Oxides, Journal of The Electrochemical Society, Vol. 170, Paper 070503.
(Open Access: PDF)
3. 2023, M. Dubarry, D. Howey, B. Wu, Enabling battery digital twins at the industrial scale, Joule, Vol.
7, Issue 6, pp. 1134-1144. (Open Access: PDF)
4. 2023, M. Dubarry, N. Costa, D. Matthews, Data-driven direct diagnosis of Li-ion batteries connectedto photovoltaics, Nature Communications, Vol. 14, Paper 3138. (Open Access: PDF)
5. 2022, M. Dubarry, et al., Perspective on Mechanistic Modeling of Li-Ion Batteries, Accounts ofMaterial Research, Vol. 3, Issue 8, pp. 843-853.
6. 2019, S. Schindler, et al., Kinetics accommodation in Li-ion mechanistic modeling, Journal of Power
Sources, Vol. 440, Paper 227117.
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

977. 2019, M. Dubarry, et al., Battery energy storage system modeling: Investigation of intrinsic cell-tocell variations, Journal of Energy Storage, Vol. 23, pp. 19-28. (Open Access: PDF)
8. 2019, M. Dubarry, et al., Battery energy storage system modeling: A combined comprehensive
approach, Journal of Energy Storage, Vol. 21, pp. 172-185. (Open Access: PDF)
9. 2017, M. Dubarry, et al., State of Health Battery Estimator Enabling Degradation Diagnosis: Model
and Algorithm Description, Journal of Power Sources, Vol. 360, pp. 59-69.
10. 2016, M. Dubarry, et al., Cell-balancing currents in parallel strings of a battery system, Journal ofPower Sources, Vol. 321, pp. 36-46.
11. 2016, M. Berecibar, et al., Degradation Mechanism Detection for NMC Batteries based on
Incremental Capacity Curves, World EV Journal, Vol. 8, Issue 2, pp. 350-361. (Open Access: PDF)
12. 2016, M. Berecibar, et al., Online State of Health estimation on NMC cells based on Predictive
Analytics, Journal of Power Sources, Vol. 320, pp. 239-250.
13. 2016, M. Berecibar, et al., Degradation Mechanisms Detection for HP and HE NMC Cells Based on
Incremental Capacity Curves, Proceeding of the IEEE Vehicle Power and Propulsion Conference(VPPC), INSPEC 16558169.
14. 2015, M. Berecibar, et al., SOH estimation and prediction for NMC cells based on degradation
mechanism detection, Proceeding of the IEEE Vehicle Power and Propulsion Conference (VPPC),INSPEC 15678053.
15. 2015, M. Dubarry, et al., State-of-charge determination in lithium-ion battery packs based on twopoint measurements in life, Journal of The Electrochemical Society, Vol. 162, Issue 6, pp. A877-A884.
(Open Access: PDF)

PRESENTATIONS:
1. 2023, M. Dubarry, et al., Effect of Temperature on Lithium-Ion Battery Voltage Response and How
to Model It in the Mechanistic Modeling Approach, Presented at the 244th Electrochemical Society
Meeting, Goteborg, Sweden, October 8-12.
2. 2023, M. Dubarry, et al., Big data for the diagnosis and prognosis of deployed energy storage
systems, Presented at the Energy Storage Systems Safety & Reliability Forum, Santa Fe, NM, June 6-8.
3. 2023, A. Fernando, et al., A Study of the Relaxation Patterns of Commercial Cells, Poster presented at
the International Battery Association Conference, Austin, TX, March 5-10.
4. 2022, M. Dubarry, Big Data in Diagnostics Data-Driven Direct Diagnosis of PV Connected Batteries,
Presented at the Advanced Automotive Battery Conference, San Diego, California, December 7-9.
5. 2022, M. Dubarry, et al., Mechanistic Li-Ion Battery Modeling, What's Next?, Presented at the 242th
ECS Meeting, Atlanta, GA, October 9-13.
6. 2022, M. Dubarry, Battery energy storage system modeling: A combined comprehensive approach,Presented at the IEEE Power & Energy Society General Meeting, Denver, CO, July 17-21.
7. 2022, M. Dubarry, et al., Big Data for Li-Ion Battery Diagnosis and Prognosis, Presented at theMaterial Research Society Spring Meeting, May 8-13.
8. 2021, M. Dubarry, et al., A New Insight into Blended Electrodes, Presented at the 240th ECS Meeting,Orlando, Florida, October 10-14.
9. 2020, M. Dubarry, et al., Synthetic Training Data for Artificial Intelligence-Based Li-Ion Diagnosis
and Prognosis, Presented at the ECS PRiME Meeting, October 4-9.
10. 2017, M. Dubarry, Non-intrusive operando battery diagnosis and prognosis, Presented at the Pacific
Rim Conference on Ceramic and Glass Technology Meeting, Waikoloa, Hawaiʻi, May 21-26.
11. 2016, D. Anseán, et al., Lithium Plating Quantification in Commercial Graphite∥LiFePO₄ Batteries,
Presented at the ECS PRiME Meeting, Honolulu, Hawaiʻi, October 2-7.
12. 2015, A. Devie, et al., Intrinsic degradation variability in commercial lithium-ion batteries,
Presented at the 228th ECS Meeting, Phoenix, Arizona, October 11-16..

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

98Hawaiʻi Natural Energy Institute Research Highlights
Appendix F: Electrochemical Power Systems
F10: Battery Electrode Optimization

OBJECTIVE AND SIGNIFICANCE: This project aims
at the optimization of battery electrodes to improve
performance by understanding local degradation
mechanisms and by tuning the electrode architecture.

experiments with materials able to intercalate andrelease sodium ions in real sea water more than
15,000 times with improved performance compared
to traditional materials (CDI).

BACKGROUND: Advanced energy conversion
devices typically rely on composites electrodes madeof several materials interacting with one another.
Understanding their individual and combined impact
on degradation is essential in the pursuit of the best
possible performance and safety. In this project, we
use our expertise in Li-ion battery diagnosis as well
as Designs of Experiments (DoE) to optimize
formulations and to investigate the importance ofprocess parameters while minimizing resources.
Figure 2. Performance characteristics of novel
intercalation materials for desalination batteries.

Figure 1. Schematic of the typical electrode architecture
for intercalation-based batteries.

Defining new approaches to minimize experiments
and time to reach an optimal battery electrodecomposition is highly beneficial to the field. To thisend, we used a DoE mixture design that was applied
for the first time in open literature to electrodeformulation. Consequently, the relationship between
electrodecomposition,
microstructure,andelectrochemical performance was uncovered.
In this project, the DoE approach was applied to two
types of electrodes: high power electrodes for lithium
batteries (ONR funded, in collaboration with the
University of Montreal) and sodium intercalationelectrodes (DOI then ONR funded, in collaboration
with Trevi Systems) to investigate the feasibility ofdesalination batteries.

In addition, our expertise in battery degradation wasused to help researchers at the Naval ResearchLaboratory to characterize the impact of local
temperature gradients on individual electrodes and byresearchers at Sandia National Laboratories toinvestigate the impact of overcharge.
Research conducted for this project is completed in
the PakaLi Battery Laboratory. This program led
to the three publications and a proceeding, which arelisted on the following page).
Funding Source: Office of Naval Research; U.S.
Department of Interior; Trevi Systems
Collaborations: University of Montreal (Canada);
University of Nantes (France); Naval ResearchLaboratory; Sandia National Laboratories
Contact: Matthieu Dubarry, matthieu@hawaii.edu
Last Updated: November 2023

PROJECT STATUS/RESULTS: This is an ongoingproject. A high-power battery system was optimizedin collaboration with the University of Montreal. This
work has led to two publications.
Current work is focused on the desalination with the
optimization of Prussian blue analogues for Na ion
intercalation in seawater. We are currently running
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

99ADDITIONAL PROJECT RELATED LINKSPAPERS AND PROCEEDINGS:
1. 2021, R. Carter, et al., Directionality of thermal gradients in lithium-ion batteries dictates diverging
degradation modes, Cell Reports Physical Science, Vol. 2, Issue 2, Paper 100351. (Open Access: PDF)
2. 2021, T.A. Kingston, et al., Altering the Degradation Mode in Li-ion Batteries Through Directional
Application of an Interelectrode Thermal Gradient, Presented at the International MechanicalEngineering Congress & Exposition, November 1-5.
3. 2020, O. Rynne, et al., Exploiting Materials to Their Full Potential, a Li-Ion Battery Electrode
Formulation Optimization Study, ACS Applied Energy Materials, Vol. 3, Issue 3, pp. 2935-2948.
4. 2019, O. Rynne, et al., Designs of Experiments for Beginners—A Quick Start Guide for Application
to Electrode Formulation, Batteries, Vol. 5, Issue 4, Paper 72. (Open Access: PDF)

PRESENTATIONS:
1. 2023, C.T. Love, et al., Evidence of the Interplay of Temperature on Local and Global Battery
Phenomena, presented at the 244th Electrochemical Society Meeting, October 8-12. Keynote presentation.
2. 2022, N. Sahin, et al, Optimization of Prussian Blue Analogues for Na-Ion Desalination
Batteries, Poster presented at the Material Research Society Spring Meeting, May 8-13. Best poster
award Symposium EN05.
3. 2022, C. T. Love, et al., How Dynamic Thermal Evaluation of Battery Electrodes and Materials Better
Replicate In-Service Operating Conditions, Presented at the Material Research Society Spring Meeting,May 8-13.
4. 2021, T.A. Kingston, et al., Altering the Degradation Mode in Li-ion Batteries ThroughDirectional Application of an Interelectrode Thermal Gradient, Presented at the International
Mechanical Engineering Congress & Exposition, November 1-5.
5. 2021, C. T. Love, et al., Electrode Specific Degradation Tailored By the Directionality of Thermal
Gradients in Li-Ion Batteries, Presented virtually at the 240th ECS Meeting, Orlando, FL, October
10-14.
6. 2021, C. T. Love, et al., Directionality of Thermal Gradients in Li-Ion Batteries Dictates Diverging
Failure Modes, Presented virtually at the 239th ECS meeting, Chicago, IL, May 30 - June 3.
7. 2019. O. Rynne, et al., Influence of the Formulation on the Microstructure and Thus Performanceof Li-Ion Batteries, Presented at the 235th ECS Meeting, Dallas, TX, May 26-30.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

100Hawaiʻi Natural Energy Institute Research Highlights
Appendix G: Advanced Materials
G1: Printable Photovoltaics

OBJECTIVE AND SIGNIFICANCE: The objective of
this program is to develop high-throughput ink-based
fabrication techniques for light-weight thin-film
photovoltaics (PV). This approach has the potential toreduce manufacturing costs and enable PV
integration on non-conventional substrates such aspolyamides or woven fabrics.

Our research is currently focused on a multicompound alloy (CuInSe2, CISe) – a material whichmeets the mechanical and weight requirements forlight weight flexible PV. HNEI’s results demonstratethat high-quality CISe solar absorbers can beachieved with this printing technology, leading tosolar cells with power conversion efficiency over 8%.

BACKGROUND: Crystalline silicon has been leading
the PV market for over 20 years. These panels, foundprimarily on roof-tops and centralized production
plants, are easily recognizable by their architecture,with interconnected wafer-like solar cells laminatedunder a flat sheet of glass. Although well-suited forstationary electrical production, the mechanicalrigidity and weight of silicon PV modules become aburden for mobile applications, where portability ismore critical than performance. To this end, R&D
efforts have focused on methods to integrate ultralight and flexible thin film solar materials onto
lightweight/flexible substrates, including plastics(polyamides) and fabrics. Such devices can generateenough electricity to power small electronic devices
for both civilian and military applications, such as
phones, electronic tablets, and sensors.

In addition, HNEI demonstrated that additives
directly incorporated into the molecular ink, such asaluminum nitrate, can passivate native defects in
CISe during fabrication, yielding to efficiency as highas 11%. Using state-of-the-art electron microscopy
analysis available at UH, the HNEI team discoveredthat aluminum nitrate reacted with oxygen during
CISe growth to form nano-sized amorphous alumina(Al2O3) grains. This new process was found toincorporate Al2O3 through the entire solar absorber’s
volume, passivating defects notably at grainboundaries and interfaces.

PROJECT STATUS/RESULTS: With support from the
Office of Naval Research, the research team at
HNEI’s Thin Films Laboratory is developing aunique method to print thin-film PV using liquid
molecular inks, which contain the raw chemicalelements necessary for the synthesis of the solar
absorber. This low-cost printing process is intended
to replace conventional vacuum-based deposition
tools, which are costly to operate and maintain.

To date, this project has produced the following
paper:• 2021, W. Septina, et al, In situ Al2O3
incorporation enhances the efficiency ofCuIn(S,Se)2 solar cells prepared frommolecular-ink solutions, Journal of Materials
Chemistry A, Vol. 9, Issue 16, pp. 10419-10426.
Funding Source: Office of Naval ResearchContact: Nicolas Gaillard, ngaillar@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

101

Hawaiʻi Natural Energy Institute Research Highlights
Appendix G: Advanced Materials
G2: Two-Dimensional Materials for Thin Film Manipulation

OBJECTIVE AND SIGNIFICANCE: Through thisprogram, our objective is to enhance ourunderstanding of interfaces formed between thin film
materials and two-dimensional (2D) layers. We strive
to explore the potential of these interfaces inphysically manipulating thin films and innovating
renewable energy conversion devices.
BACKGROUND: Monolithic integration – the process
by which solid-state devices are made by sequentiallydepositing layers of materials on top of each other –is used in all commercial thin film-based technology.
This process is so foundational that it is difficult toimagine any other way to create solid-state devices.
Despite its wide acceptance, however, monolithic
integration presents two major limitations. First,
process compatibility is a challenge since thedeposition of each layer must not damage thepreviously deposited underlying layers in any way.
As such, the thermal, mechanical, and chemicalcompatibility between layers and their deposition
processes is of prime importance, restricting materials
selection to a sub-set of compatible systems andlimiting the adoption of emerging promising
candidates. Second, monolithic integration almost
always leads to the formation of additional phases at
the interface of two materials. The electronic andchemical properties of interfaces also generally differ
significantly from those of a simple combination of
the two constituting layers, impacting device
performance.
An integration scheme that combines materials
regardless of their nature, while preserving or evenenhancing their intrinsic performance, could
revolutionize
manufacturingofrenewabletechnologies that rely on material stacking, including
photovoltaic (PV) devices. Such an integration
approach – using 2D materials for thin film
manipulation – is proposed in this program.

In this project, the University of Hawaiʻi (UH) andthe University of Nevada, Las Vegas (UNLV)
partnered with the Lawrence Livermore National
Laboratory (LLNL) and National Renewable Energy
Laboratory (NREL) to develop the concept of 2D
material-assisted thin film exfoliation, focusing on
the chalcopyrite class (e.g., Cu(In,Ga)Se2, CIGSe)
and transition metal dichalcogenides (e.g., MoS2 andMoSe2) 2D interfacial layers that can naturally form
when sulfur- or selenium-containing semiconductors
are deposited onto transition metal substrates.
PROJECT STATUS/RESULTS: Current efforts arefocused on: 1) the exfoliation of commerciallyavailable 2D materials; 2) the characterization of theirchemical properties using advanced spectroscopic
techniques; and 3) the theoretical modeling of theirenergetics when interfaces with CIGSe. Grapheneand MoSe2 2D layers were isolated through themechanical exfoliation method. Flakes of bothmaterials were delaminated from bulk seed crystals
by pressing a transfer strip onto them. The process
involved folding the tape on itself a predetermined
number of times to further separate the remaining
crystals. Subsequently, these separated layers weretransferred onto silicon wafers. X-ray photoelectron
spectroscopy and Raman spectroscopy carried out at
UNLV and HNEI, respectively, evidenced the 2D
nature of the layers isolated with HNEI’s method.
Lastly, theoretical modeling efforts conducted at both
UH and LLNL focused on understanding the impact
of mechanical strain on the energetic properties of 2D
materials. This crucial information will be
instrumental in analyzing how mechanicaldeformation, such as stretching or bending, affects theperformance of PV devices.
Funding Source: Department of Energy
Contact: Nicolas Gaillard, ngaillar@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

102

Hawaiʻi Natural Energy Institute Research Highlights

Appendix G: Advanced Materials
G3: Encapsulation of Perovskite Solar Cells for Long Term Operations
OBJECTIVE AND SIGNIFICANCE: The objective of
this program is to extend the lifetime of low-cost, highefficiency perovskite solar cells (PSCs) to meet the
U.S. Department of Energy’s 2030 cost target of$0.02/kWh.
BACKGROUND: Since the first report of PSCs in2009, tremendous research efforts on absorberchemistry have boosted the power conversion
efficiency of this material class from 3.9% to 25.7%.
Although impressive, this attribute alone cannot
guarantee the commercial success of PSCs, as any
emerging technology must also meet the 20-25 year
stability already achieved by other mature
photovoltaic (PV) classes. To date, the durability ofbest performing PSCs is limited to few months at best,
constituting an important roadblock in theirdeployment. In this project, HNEI partnered with the
National Renewable Energy Laboratory (NREL) toaccelerate the development of unique protection
schemes to enhance PSCs’ lifetime. Specifically, ourteam aims at eliminating two stress factors andtechnical barriers responsible for PSC degradation: 1)
high temperatures during processing and 2)
atmospheric effects during PV operations.
PROJECT STATUS/RESULTS: HNEI has developed a
new composite integrating multi-functionalities suchas corrosion resistance, lightweight, and flexibility as
well as tunable optoelectronics. Unlike mostconductive flexible polymers, where media are coatedon top providing only in-plane conductivity, HNEI’stransparent conductive composites (TCC) innovateby allowing simultaneous high optical transparency(%T>90% in the 370nm-2000nm region) and highout-of-plane electrical conductivity (R<0.2 Ω.cm2).
This unique characteristic is permitted by highly
conductive 50-micron Ag-coated PMMA spheres
protruding out of a transparent non-conductive
polymer.

In this project, TCCs serve as gas-barrier locatedbetween the PSC and metal top contacts, providing a
conformal hermetic seal repelling moisture andoxygen while preventing out-diffusion of volatile
species. TCCs offer at least three main advantages
over traditional “glass-glass” encapsulation. First, ourcomposite fully cures at room temperature, whichtackles the first barrier and eliminates all adverse
thermal effects encountered in conventional
sealant/adhesive technologies (which require curing
above 100°C). Also, the protruding particles in TCC
act as direct electrical access points to the underlaying
structure. Therefore, the coating is not spatiallyrestricted and can be applied directly on top of the
PSC and can extend to the device edges, sealing
directly the top and sides of the PV stack to theoperating environment, which addresses the second
barrier with no risk of lateral electrical shorting.
Finally, there is no need for an extra encapsulating
glass cover with TCCs, reducing module weight andcost.
Our team has demonstrated that TCCs can maintainvirtually 100% of their optical and electricalproperties for over 1,000 hours of outdoor exposure
under Hawaiʻi’s tropical semi-arid climate, while
TCC-coated PSCs preserve over 90% of their initial
efficiency after 1,000 hours of accelerated testingunder 45% relative humidity at 50°C. Current efforts
are focused on reducing TCC’s water vapor andoxygen transmission rates to meet packaging
standards. To date, this project has produced“Transparent Conductive Composites—A New
Class of Encapsulants for Durable Perovskite
Photovoltaics”, presented at the MRS Spring 2023
meeting.
Funding Source: Department of Energy; Energy
Systems Development Special FundContact: Nicolas Gaillard, ngaillar@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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103

Hawaiʻi Natural Energy Institute Research Highlights

Appendix G: Advanced Materials
G4: Develop Reversible Liquid Hydrogen Carriers Containing Magnesium Boranes
OBJECTIVE AND SIGNIFICANCE: The objective of
this project is to develop a commercially viable, twoway liquid hydrogen carrier (LOHCs) based on
solutions of metal hydrides in heterocyclic LOHCs
that have a greater energy efficiency and lower
delivery costs than existing hydrogen carriers andconventional compressed H2 gas transporttechnology. The successful development of the liquidhydrogen carriers would support acceptance andexpansion of hydrogen and fuel cell technologies.
BACKGROUND: A substantial network of tanker
trucks and pipelines to transport hydrogen at ambient
temperature and pressure already exists. The LOHCs
of interest in this work would be able to utilize thisinfrastructure. Both one-way carriers, which form
benign products upon elimination of hydrogen thatare released to the environment, and two-way LOHCs
which can be cycled between their hydrogenated anddehydrogenated phases have been investigated. A
recent comparative cost and energy consumption
analysis of LOHCs performed at Argonne National
Laboratory showed the one-way carrier, methanol tobe the strongest candidate. However, it showed no
overall cost advantage over tube trailer delivery ofcompressed hydrogen and pointed to the need todevelop new hydrogen carriers.
Methylcyclohexane, the prototypical two-way LOHC
has enthalpy of dehydrogenation of 69 kJ/mol H2,
which is a major drawback to its utilization inpractical systems as its dehydrogenation is
intrinsically energy extensive. It also has a relatively
low volumetric available hydrogen density of 47 g/L
which translates to a high cost of hydrogen transport.
Heterocyclic LOHCs have excellent thermodynamic
properties but are challenged by low volumetricavailable hydrogen densities which impose an
economic barrier to their application as practicalhydrogen carriers. Our approach to overcoming thisbarrier is the addition of high density hydrogenstorage materials, especially Mg(BH4)2, to theheterocyclic LOHC which can result in up to 19%
increase of the available volumetric hydrogendensity. The enhanced density, up to 100 g/L, is morethan double that of methylcyclohexane.
In collaboration with UH’s Department of Chemistry
and the DOE-HyMARC Consortium (including

Pacific Northwest Laboratory and National
Renewable Energy Laboratory), this project targets
the generation of two-way LOHCs by charging
selected heterocyclic LOHCs with borohydrides. The
project
aims
toidentify
thebestheterocycle/hydride/catalyst combination in terms ofrate, cycling capacity, and product selectivity withgoal of maximizing energy efficiency of hydrogenstorage and delivery.
PROJECT STATUS/RESULTS: The initial studies werefocused on synthesis and characterization of a varietyof ionic liquid borohydride LOHCs materials, as wellas, carbazole and pyridine-based borohydride
LOHCs. Characterization of the synthesizedmaterials was performed using nuclear magnetic
resonance spectroscopy (NMR), infrared vibrational
spectroscopy (FTIR) and thermogravimetric analyses(TGA-DSC). The vibrational spectroscopy confirmed
the typical borohydride peaks in the 2200-2500 cm-1
and 1100-1400 cm-1 region whilst 11B solution NMR
spectroscopy directly confirmed the BH4- ion peaks,
at -36 to 39 ppm region. The dehydrogenation of thematerials was performed below 200°C. Attempts tore-hydrogenate the materials in Parr Inc. highpressure reactors vessels were unsuccessful inpresents and absents of Ru and Pd based catalysts.
The next phase of the project was focused on
preparation and (de)hydrogenation performancestudies of N-heterocycle-magnesium borohydride(LOHC-Mg(BH4)2) solutions with and withoutcatalyst. These studies are meant to allow theidentification of the optimal N-hetrocycle based
LOHC-Mg(BH4)2
solutions/emulsionsfordevelopment as hydrogen carriers. The Nheterocycles analyzed included (de)hydrogenatedindole,methylimidazole
1,4-bipiperidine,morpholine, butyl-imidazole, N-methylindole, 1,2
dimethy-imidazole, quinolone, and pyrrolidine.
The LOHC-Mg(BH4)2 screening reactions were
performed in Parr mini-reactors at 180-200°C for up
to 24 hours. Hydrogen evolution from the solutions
was confirmed by the increase in pressure of thereactor vessels. Analyses of the dehydrogenatedmaterials was performed utilizing 1H and 11B NMR.
Products formation upon H2 release from the LOHCMg(BH4)2 samples was confirmed by 11B peaks at -23
to -31 ppm (cyclic B-N species) and -5 to -18 ppm

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104

N-BHx (borane species). The best dehydrogenated
Mg(BH4)2-LOHC mixtures based on NMR resultsand H2 release pressure were N-heterocycles
solutions containing 1,4-bipiperidine, morpholine,
and pyrrolidine. The 1:6 Mg(BH4)2/pyrrolidine
emulsions were found to release the most hydrogen,at 49 to 52 g H2 /L.
The re-hydrogenation of the best N-heterocycles was
performed at 180°C for up to 72 hours. The catalysts
utilized in the re-hydrogenation reactions of theheterocycles-Mg(BH4)2 were Ru/C and Ru/Al2O3 at
5-10 wt%. However, none of the dehydrogenation
products were discovered to undergo rehydrogenationback to the starting materials under hydrogen pressureof 80-120 bars.
a)

The dehydrogenation of the Mg(BH4)2/pyrrolidine
emulsionswasdiscovered
toform
trispyrrolidinoborane, B{N(CH2CH2)}3 complex
with a peak at -23 ppm (Figure 1a). As seen in the
NMR spectra (Figure 1b), there is no evidence of thereformation of the Mg(BH4)2 after re-hydrogenationof the product. The Mg(BH4)2 normally occurs as apeak with a chemical shift at ~ -41 ppm in 11B NMR
spectra. The re-hydrogenation back to Mg(BH4)2 or
boranes is hindered by the challenge of addinghydrogen across the highly stabilized B-N bonds ofthe trispyrrolidinoborane.
Our future work will continue to explore thediscovery of new LOHC-Mg(BH4)2 type systems
which can be rehydrogenated using catalysts.
However, in light of the challenges of rehydrogenationoftheLOHC-Mg(BH4)2
solutions/emulsions to borohydrides or boranes that
we have studied to date, we will be exploring newalternative routes generated through this project suchas the reversible (de)hydrogenation of theheterocyclic rings of trispyrrolidinoborane, (TPB) togive trispyranoborane, (TPyB) (Figure 2).
- 6 H2

Figure 2. Dehydrogenation of trispyrrolidinoborane totrispyranoborane.

b)Funding Source: U.S. Department of Energy; Energy
Systems Development Special FundContact: Godwin Severa, severa@hawaii.edu
Last Updated: November 2023

Figure 1. 11B NMR of Pyrrolidine + 6 Mg(BH4)2 mixture(a) dehydrogenated at 180°C for 24 hours followed by (b)re-hydrogenation at 180°C for 72 hours.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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105

Hawaiʻi Natural Energy Institute Research Highlights
Appendix G: Advanced Materials
G5: Forward Osmosis Draw Solutions for Seawater Desalination

OBJECTIVE AND SIGNIFICANCE: The objective of
this project is to fabricate a forward osmosis (FO)system and develop novel inorganic salts and ionicliquid draw solutes for use as energy efficient, highwater flux, and low toxicity draw solutions in FO
water purification. If successful, the novel draw
solutes would lead to efficient sea water and brackish
water purification using minimum amount ofelectrical energy compared to current state of art
reverse osmosis (RO) or FO technologies.
BACKGROUND: FO is a promising low pressure water
purification technology with low electrical energy use
potential that is less hindered by the drawbacks ofhigh hydraulic pressure of RO water purification
technology. The widespread commercialization of
FO technology is challenged by a lack of practical,
cost competitive draw solute materials with highosmotic pressure and low reverse draw solute
diffusion that can be efficiently separated from thedesalinated water.

processes incorporating renewable energy sources or
low grade energy sources, such as waste heat.
Over the last year, we finalized the benchmarking of
the performance of the custom fabricated FO systemusing commercial draw solutes (potassium chloride
and ammonium chloride) to allow for in-depth draw
solutions (DS) development and evaluation. We
screened the performance of various draw solutions(including potassium lactate, EMIM acetate, glucose
and potassium gluconate) on the optimized FO
system using DI water or seawater obtained from Ala
Moana beach as feed solutions. The performance
evaluation of draw solutions using seawater as feedsolution, indicated relatively high-water recovery andwater flux with the new draw solutions of potassium
lactate and EMIM acetate ionic liquid. The nontoxicity of the potassium lactate draw solution makes
it usable for multiple applications. Further work will
include optimizing the potassium lactate water
recovery and regeneration process.

FO offers opportunities for higher water recovery
efficiencies and lower membrane fouling. FO uses theosmotic pressure of a concentrated draw solution topull water at low pressure with subsequent recoveryof the fresh water from draw solute. A variety of draw
solutes, including metal salts, organic compounds andsynthetic materials (e.g. polymers, hydrogels) havebeen studied to date. Responsive solutes that canfacilitate the separation of the draw solute from thedesalinated water offer the greatest promise. For
instance, the state of art ammonia/carbon dioxide
thermally responsive draw solute is efficient in water
recovery. However, the draw solute is hindered by the
incomplete recovery of the ammonia, therefore, thedesalted water remains contaminated with residual
ammonia. Hence, novel draw solutes are needed inorder to fully realize the intrinsic benefits of forward
osmosis water purification technology compared tostate of art technologies.
PROJECT STATUS/RESULTS: Our research is focusedon fabricating a precise and accurate FO water
purification system, followed by development of
inorganic salts and ionic liquid based draw solutes
with high desalination performance that can be
efficiently separated from water utilizing thermal,
electrochemical, or magnetic draw solute recovery

Figure 1. Mass of water recovered from Ala Moana
Seawater feed solution over time (top) and thecorresponding change in water flux (bottom).

Funding Source: Office of Naval ResearchContact: Godwin Severa, severa@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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106

Hawaiʻi Natural Energy Institute Research Highlights

Appendix G: Advanced Materials
G6: UH and UW Materials Research and Education Consortium (MRE-C)OBJECTIVE AND SIGNIFICANCE: The objective of
the University of Hawaiʻi (UH) and University ofWashington (UW) Partnership for Research and
Education in Materials (PREM) program is todevelop foundational knowledge about advanced
nano-to-macroscale defect-bearing and doped
materials and the properties controlling their uniquebehaviors, and investigate their use for future energy
technologies. If successful, the project would develop
the foundation necessary for increasing participationin materials science and STEM at undergraduate andlater graduate level by underrepresented groups(URGs), enabling diverse student participants toperform research at the frontiers of the world’s
greatest materials research challenges.
BACKGROUND: This project is focused on increasing
Materials Science and STEM participation by unique
URGs – in particular, Native Hawaiians and PacificIslanders (NHPI), women, and Veterans to equity –by creating a pathway that recruits and retains
participants and keeps them on track towards degree
attainment. The Seed PREM is configured tocapitalize on synergistic expertise and exceptional
resources in materials syntheses and characterization
available at UH and UW to create closeinterdisciplinary research collaborations emphasizing
the education and training of a diversified next
generation of scientists and engineers.
The project research on defect-bearing and doped
materials is organized into four thrusts aligned with
UW’s Materials Research Science and Engineering
Center Interdisciplinary Research Groups (MRSEC
IRGs): 1) dopant control in boron compounds for
tailored gas sorption; 2) defect modeling,
characterization, and engineering in ordered vacancy
compoundchalcopyrites
forphotovoltaic
applications; 3) the role of hydrogen in the chemistryof proton-irradiated solids; and 4) strain control ofelectronic and magnetic properties of solid materials.
The results of this research will lead to new materials
and the understanding of new phenomena critical forsolving emerging needs in energy storage and durable
space technologies.
PROJECT STATUS/RESULTS: The research andeducation initiatives are targeted to encompass:strong student dual-mentoring by both UH and UW
senior participants, annual in-person faculty/student

summer research exchanges complimented by regular
virtual exchanges, UH-UW co-development ofteaching materials, and an annual student symposium.

Figure 1. Student presentation during 2022 summer
research experience at UW.

The main focus of the last year was the retainment ofstudents in the four research thrusts through the full
realization of M.O.R.E. strategy, encompassing
mentoring (M), outreach (O), materials research (R),and materials science education (E). The student
research activities were focused on design andsyntheses of materials and/or characterization of thematerials using general lab equipment and specialized
instruments. A total of 24 UH-UW exchanges haveassisted with students’ retainment on the partnershipto date, including 8 student exchanges during thisperiod.

Figure 2. Strategy and goals of the PREM program.

In March 2023, a two-day MRSEC faculty exchange
visit to UH occurred. The visit focused on
accelerating and expanding research and education
activities in the PREM thrusts. Student researchpresentations, informational sessions for students,
and UH campus laboratory and facility tours also took

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107place over these two days. Fifteen faculty members
from UW and UH spanning seven various disciplines,
along with UH’s Provost, attended these meetings.
During this visit, the need for location-based researchand education in the PREM to solve Hawaiʻi’smaterials challenges was seen as an important area toconsider moving forward.

Figure 5. PREM faculty and students participating at the2023 Kamehameha Schools’ science fair.

Funding Source: National Science Foundation
Contact: Godwin Severa, severa@hawaii.edu
Figure 3. MRSEC faculty exchange visit in March 2023.

Last Updated: November 2023

The PREM outreach efforts for building andsustaining the URG pipeline into materials scienceand STEM at UH continue to be based on a bottomup strategy centered on active engagement of Hawaiʻischools to spark early interest in STEM and materials
science. Hence, we expanded our outreach activities
to five public schools (ʻIlima Intermediate, Kaiser
High, Radford High, UH Laboratory School, andWaipahu High) to complement our continued
outreach efforts to Kamehameha Schools.

Figure 4. PREM research student outreach efforts duringa K-12 student visit.

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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108

Hawaiʻi Natural Energy Institute Research Highlights
Appendix G: Advanced Materials
G7: Development of Novel Air Filtration Materials

OBJECTIVE AND SIGNIFICANCE: The objective of
the project is the design, synthesis, andcharacterization of novel, reversible highperformance acidic gas (SOx, NOx and H2S)
contaminant absorbent materials. The materials underdevelopment would enable fuel cell vehicles to beefficiently operated under harsh atmospheric air
environments. If successful, sorbents underdevelopment will assist the fuel cell filter industry andreduce environmental contamination from hazardous
absorbent waste.
BACKGROUND:
Current
state-of-the-art
gas
purification technologies for acidic gas capture basedon metal oxides and hydroxides do not meet all of theperformance requirements of today’s gas purificationin terms of sorption: kinetics, capacities, selectivity
and reversibility. This leads to large volumes ofpolluted absorbent waste. This situation can be
expected to worsen in the future with the increased
use of fuel cell vehicles that require abundant
efficiently purified air as oxygen source.
The sorbent classes under development include ionicliquids, metallo ionic liquids, and metal organic
framework-activated carbons. The sorbent material
properties are optimized through a combination ofcareful selection of reactants and modification of thesorbent cation and anion groups. For instance, metallo
ionic liquids with a high content of the small, highly
charged acetate and croconate groups, and transition
metal
ions
with
expandable
coordinativeenvironments are being designed, synthesized, andcharacterized.
PROJECT STATUS/RESULTS: Nano confinement of
the absorbents in highly porous materials is being
performed in order to increase acidic gas-sorbent
interactions and hence gas sorption performance.
Nano confinement is especially critical for ionicliquids absorbents since they have high viscosity,
which limit gas diffusion distances into the bulk of thematerial. We have physically deposited thin films of
1-ethyl-3-methyl imidazolium acetate ionic liquid
onto activated carbon that remain intact duringexposure to SO2 and/or NO2 contaminated air streams.
The sorbents being developed also have relevance inother applications requiring acidic gas (SOx, NOx andH2S) contaminant mitigation, including flue gas
cleaning and natural gas purification.

We synthesized and characterized metal containing
ionic liquids (metallo ionic liquids) containing Zn,
Mg, Fe or Mn cations with general empirical formula
Mx(OAc)y[EMIM]z. About 5 wt% or 10 wt% of thesynthesized metallo-ionic liquids (MIL) were
supported onto nano-porous coconut based activatedcarbon. The activated carbon-metallo ionic liquids
absorbents were screened for their potential to filter
elevated levels of sulfur dioxide (10 ppm in simulatedair) using a custom designed and fabricated filtrationmaterials test stand. The lab scale tests were
performed at 1-2 LPM and relative humidity of 4050%. The initial results indicate higher sulfur dioxide
break through times with the Mg and Zn MILactivated carbon absorbents (Figure 1).

Figure 1. Comparative studies of sulfur dioxide (SO2)breakthrough curves for 5 wt% metallo ionic liquids
supported onto nano-porous activated carbon under achallenge gas of 10 ppm SO2 with balance purified air.

Further work will involve optimizing theperformance testing and integration of the developed
absorbents with commercial media to form improved
hybrid multiple gas contaminant filter media withhigher breakthrough filtration performance underharsh environments with elevated levels of gas
contaminants.
Funding Source: Office of Naval ResearchContact: Godwin Severa, severa@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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109

Hawaiʻi Natural Energy Institute Research Highlights
Appendix H: Ocean Energy
H1: Research Support to the U.S. Navy Wave Energy Test Site

OBJECTIVE AND SIGNIFICANCE: Wave energy has
the potential to address global renewable energy
goals, yet it poses daunting challenges related tocommercializing technologies that must produce
cost-competitive electricity while surviving anenergetic and corrosive marine environment. The
nascent commercial wave energy sector is thus
critically dependent on available test infrastructure toadvance development of wave energy conversion(WEC) devices and related technologies. For thisreason, the U.S. Navy established the Wave Energy
Test Site (WETS) in the waters off Marine Corps
Base Hawaiʻi (shown below) as the United States’
first grid-connected site, completing the buildout in
mid-2015. WETS consists of test berths at 30m, 60m,
and 80m water depths, and can host point absorberand oscillating water column (OWC) devices to apeak power of 1 MW.
HNEI provides key research support to this national
effort in the form of environmental monitoring,
independent WEC device performance analysis, andcritical marine logistical support. The results
achieved at WETS have far reaching impacts in termsof advancing wave energy globally.

development (power output versus wave height andperiod), numerical hydrodynamic modeling, and aregimen of regular WEC and mooring inspections;and 3) logistics support, in the form of past funding
to modify a site-dedicated support vessel for use at
WETS, through local partner Sea Engineering, Inc.,
assisting WEC developers with deployment planningand through funding to developers for maintenanceactions during their WEC deployments at the site.
In Summer 2021, NAVFAC granted HNEI an
additional $6M to continue this core support to
WETS, and to expand research related to smallerscale WECs for offshore, non-grid-connected
applications of wave energy. This includes: 1)
examining the potential for existing WETS
infrastructure to support the creation of an offshore
test and demonstration node, including subsea power
storage as well as communications and powerinterfaces that would allow small WECs to power
applications such as autonomous undersea vehicle(AUV) recharge, environmental/environmental
sensing, and navigation; 2) design of an AUV
docking/charging station for WETS; 3) developmentof a power generation and management system for a
floating OWC device of UH design for applications
such as ocean observation and AUV recharge; 4)advancement of a novel breakwater system withintegrated OWC power generation; and 5) concept
development of a floating flap-type WEC.
In Summer 2022, an additional $3.6M was awarded
by Navy to further extend core support to WETS,
including key infrastructure upgrades/maintenance.

BACKGROUND: Wave energy has enormous potential
to supply persistent power to these non-gridconnected applications, as well as to aquaculture, atsea mineral scavenging, and providing renewable
power to remote or island communities. Through a
cooperative effort between the Navy and the U.S.
Department of Energy (DOE), WETS hosts
companies seeking to test their pre-commercial WEC
devices in an operational setting. HNEI works with
the Navy and DOE to directly support WEC testing at
WETS in three key ways: 1) environmental impact
monitoring – acoustic signature measurement andprotected species monitoring; 2) independent WEC
device performance analysis, including wave
forecasting and monitoring, power matrix

PROJECT STATUS/RESULTS: Since mid-2015, thefollowing major activities have occurred at WETS,
with HNEI in both supporting and leading roles:• Jun 2015 to Dec 2016: Northwest Energy
Innovations deployed Azura device at 30m berth.

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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110• Mar 2016 to Apr 2017: Sound and Sea
Technology deployed Fred. Olsen Lifesaver at
60m berth. This project was not grid-connected.

• Feb to Aug 2018: HNEI led a second deploymentof Azura, with modifications designed to improve
power performance, including enlarging the float
and adding a heave plate at the base.

• Oct 2018 to Mar 2019: HNEI led effort toredeploy Lifesaver at 30m with modifications tomoorings and integration of UW sensor package
and subsea charging capability, which drew its
power from the WEC itself. This use of wave
energy to power an offshore sensing suite was animportant national first.

•

May/Jun 2019: HNEI led a major redesign andreinstallation effort for the WETS deep berthmoorings. 60m berth was reinstalled, 80m berth
repairs held, subject to WEC developer demand.

•

Nov 2019: Completion of site-dedicated support
vessel Kupaʻa by research partner Sea
Engineering, Inc. This vessel adds significantly to
our ability to perform various functions at WETS.

Issues stemming from COVID, funding, andtechnical challenges have substantially delayedplanned WEC deployments over the past few years,
but three deployments are currently happening, orplanned in the coming year:
1. Deployment of the Oscilla Power (Seattle)
Triton-C community-scale WEC at the 30m
berth. This device arrived in Hawaiʻi in October
2021. New anchors were deployed at the WETS
30m berth in support of this project, with work
complete in August 2022, and a newelectrical/data junction box was installed in

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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111September 2023. The latest expectation for
deployment of the device is late fall 2023.

3. Deployment of the Ocean Energy (Ireland)
OE35 WEC at the 60m berth. This device has
been in Hawaiʻi since December 2019, andunderwent drydock repairs in Aug/Sep 2022,
after extensive delays. It is currently undergoing
replacement of key electrical components, andfinal testing, and should be ready for deployment
to WETS in late 2023 or early 2024.

2. Deployment of the C-Power SeaRay WEC. Thisis a stand-alone (not grid-connected)
deployment of a small, 1kW device that will
feed power to a subsea acoustic sensing systemfrom Biosonics, as well as other environmental
sensors. The device was deployed at WETS inearly October 2023, but suffered some earlydamage and will need to be redeployed at afuture date.
Funding Sources: Naval Facilities Engineering
Command, Expeditionary Warfare Center; U.S.
Department of Energy
Contact: Patrick Cross, pscross@hawaii.edu
Last Updated: November 2023

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University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
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112

Hawaiʻi Natural Energy Institute Research Highlights
Appendix H: Ocean Energy
H2: The Hawaiʻi Wave Surge Energy Converter (HAWSEC)OBJECTIVE AND SIGNIFICANCE: The objective of
the Hawaiʻi Wave Surge Energy Converter(HAWSEC) project, funded primarily by the U.S.
Department of Energy (DOE), is to mature a wave
energy converter (WEC) concept developed by the
HNEI-led team, that could ultimately produce costeffective renewably generated electricity for coastal
communities. The project is expected to makeimportant advances in the emerging wave energy
field and has the potential to mature a technology withrealizable commercial potential in the future – for
Hawaiʻi, the U.S., and beyond.
BACKGROUND: HNEI has been involved insupporting research and testing objectives at the U.S.
Navy’s Wave Energy Test Site (WETS), off Marine
Corps Base Hawaiʻi, since 2010 with funds from both
DOE and the U.S. Navy (Naval Facilities Engineering
Command: NAVFAC). Through this involvement,
HNEI has gained valuable practical experience
associated with real-world deployment and operationof WECs in this first-of-its-kind in the U.S. gridconnected test site. Additionally, through numericalmodeling of WEC dynamics and mooring systems insupport of WETS test objectives and WEC
developers, HNEI has accumulated key design
insights and numerical modeling expertise related to
WEC design.

Figure 1. HNEI’s HAWSEC system in Oregon State
University’s wave basin for testing.

The HAWSEC concept is based on the oscillating
wave surge converter (OWSC), or flap-type WEC.
Such systems rely on the surge motion of the waves
close to shorelines, where wave direction becomes
more consistent than offshore. The flap moves backand forth in the waves and drives hydraulic cylinders
to pump water through a hydro turbine to generate
electricity. Its inherent scalability could support
smaller-scale generation for isolated communities orislands, or larger-scale devices (likely deployed inarrays) to generate power to feed into coastal power
grids. The small-scale version of the flap is shown in
Figure 1.

PROJECT STATUS/RESULTS: This project wasinitated in August 2020. HAWSEC development isproceeding along the following broad set of tasks:
1. Numerical modeling of small-scale version,
nominally a 1m x 1m flap, to optimize design;
2. Fabrication and local testing of the small-scale
system – both the hydraulic system and the flap
itself in nearshore waters on Oʻahu;
3. Controlled tank testing of the small-scale system
at Oregon State University’s (OSU) Hinsdale
wave basin;
4. Validation of numerical modeling with test
results from OSU;
5. Numerically scaling up to medium scale,nominally a 3m x 3m flap, and completing abuildable design of the HAWSEC at this scale;
6. Undergoing a Go/No-Go decision with DOE;
7. Fabrication of a full medium-scale system,
including flap and hydraulics;
8. Controlled tank testing of the medium-scale
device at the University of Maine’s test flume;and9. Validation of medium-scale numerical models
with test data from Maine, and modeling andperformance prediction for a full-scale version
of HAWSEC.

We are exploring both a high-head/low-flow and a
low-head/high-flow hydraulic system – utilizing thesame flap in the first half of the project – ultimately
settling on an optimized configuration with a hydroturbine selected to best align with the optimized head
and flow before scaling up for additional testing in thelatter stages of the project.

To date, Tasks 1 through 4 above are now complete.
The smaller-scale flap system, including the flap
itself and both versions of the hydraulic power takeoff(PTO) system, was designed and fabricated in 2021
and early 2022. A hydraulic bench test setup wascompleted in our lab on the UH campus in early 2022,
including a linear actuation system that is capable of

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113simulating realistic wave forcing. Lab testing was
carried out between January and May 2022, resulting
in readiness to ship the full system to Oregon for wave
basin testing at OSU.
Nearshore testing of the flap in local waters at Makai
Research Pier was conducted in May 2022 (Figure 2),
with encouraging results that further de-risked theupcoming basin tests.

Figure 3. Controlled wave basin testing at OSU.

A Go/No-Go decision process with DOE will be
undertaken in February/March 2024, and the projectis expected to reach completion in the spring of 2025.
This extended timeline stems from substantial
procurement challenges in Budget Period 1 and ashipping-related setback, which cost the project
several months. Despite these delays, the project ismeeting its technical objectives and has resulted in a
WEC concept that is of high interest to DOE and to
our partners at the National Renewable Energy Lab,
who are now working with us to initiate a new projectthat will utilize our small-scale flap for a PTO
development of their own and subsequent
deployment at Makai Pier.
Figure 2. Flap testing at the Makai Research Pier.

Controlled wave basin testing at OSU was completed
in two phases, without and with a power takeoff(hydraulic) system, in June and October/November
2022 (Figure 3). Excellent results were obtained,
particularly for the high-head PTO, where the power
produced exceeded expectations. Due to this, thehigh-head PTO – in which a hydraulic cylinder
pumps water at high pressure through a nozzle torotate a Pelton wheel turbine – is the selected
approach for the second phase of the project, where
the device will be scaled up in size with the goal of
conducting subsequent testing and validation.

Funding Source: U.S. Department of Energy, Water
Power Technologies Office; Energy Systems
Development Special FundContact: Patrick Cross, pscross@hawaii.edu
Last Updated: November 2023

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114

Hawaiʻi Natural Energy Institute Research Highlights
Appendix I: International
I1: Asia Pacific Regional Energy System Assessment (APRESA)OBJECTIVE AND SIGNIFICANCE: In August 2017,
HNEI was awarded a grant from the Office of Naval
Research (ONR) to support energy system transitions
in select locations throughout the Asia-Pacific region
under the Asia Pacific Regional Energy System
Assessment (APRESA) program. The objective of
APRESA is to develop comprehensive energy systemassessments in the Asia-Pacific region regarding
energy transition strategy, policy, regulation,technology options, demonstrations, implementationplans, and training based on the specific requirements
or needs of the targeted jurisdictions and strategic
alliances.
BACKGROUND: During the six years of APRESA
activities, HNEI established substantive strategic
partnerships with national, regional, and local
jurisdictions, as well as private and public
stakeholders
includingnumerousutilities,
universities, and other research and international aid
and development entities, such as the World Bank
(WB), Asian Development Bank (ADB), AustralianInfrastructure Financing Facility for the Pacific(AIFFP), The Asia Foundation (TAF), The Maureen
and Mike Mansfield Foundation (TMF), U.S. Agency
for International Development (USAID), and U.S.
Department of Defense (DOD) organizations in theareas of interest. Based on the programmatic successof these strategic partnerships, ONR has extended the
APRESA program for an additional two years
through 2024.
Nations with ongoing active engagement and support
activities include Vietnam, Thailand, Laos,
Indonesia, Papua New Guinea, and the Philippines.
New engagements with Pacific Island countries (PIC)
include Palau, Cook Islands, the Republic of the
Marshall Islands, and the Commonwealth of theNorthern Mariana Islands. The criteria for selectionof jurisdictions include: 1) those with significant rates
of projected demand growth requiring rapid energy
system expansion and transformation, 2) strategic
trade and geopolitical opportunities to the UnitedStates, 3) potential to integrate renewable energy
technologies, and 4) a collaborative environment to
conduct the work.
In addition to the deep local partnerships formed inthese jurisdictions, this program has led to a highly
successful collaborative relationship with the U.S.

Agency for International Development (USAID) and
its implementing prime contractors throughout theregion (e.g., Deloitte, Tetra Tech, Abt Associates,
RTI, Chemonics, and Delphos International).
USAID partner country governments need highquality technical expertise to guide their decisionmaking and can learn from the experience of moredeveloped countries using their best practices andcase studies. With significant experience providing
technical expertise in the renewable energy space,
HNEI is uniquely positioned to partner with USAID
and provide energy intelligence in identifying tailoredsolutions for jurisdictions in need. This collaborative
approach, leveraging the capabilities, resources, andknow-how of HNEI and USAID implementing
contractors in the Asia-Pacific region is consistent
with the U.S.’ whole-of-government strategy to growsustainable and secure energy markets across theregion. Achieving self-reliance enables emerging
economies to rely less on external aid in times ofcrisis, promotes more transparent markets thatincentivize private investment, and redirects
resources from inefficient energy subsidies toward
more productive utilization. Low-cost renewableenergy has the potential to improve the financial
viability of energy sectors, reduce vulnerabilities tomalign and climate change influences, and improve a
country's overall ability to finance its self-reliance.
HNEI’s collaborations and interventions under thisgrant help deliver technical expertise to policymakers
in emerging economies that can aid in achieving
lower-cost, cleaner energy solutions that catalyze
competitive markets and reduce carbon emissions –ultimately enabling their populations to enjoy
universal, reliable, and cleaner electricity services.
HNEI is using the remaining APRESA funding toextend the efforts in the current countries and to
expand this work to other countries, regions, and
DOD facilities of interest, with particular focus on
PICs. These efforts are supported by a number of
HNEI faculty and staff, including those of the HNEI’s
GridSTART team focused on advanced gridtechnologies and enabling policy and regulation.
PROJECT STATUS/RESULTS: A number of selectprojects initiated under the APRESA award aresummarized below. Many of these are also described

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115

in more detail in separate project summaries in thisAppendix.
Innovation System Mapping Project in the
Renewable Energy Sector in Vietnam
Under this effort, HNEI provided financial support
and guidance, to the National Institute for Scienceand Technology Policy and Strategy Studies(NISTPASS) to map the innovation opportunities
associated with renewable energy (RE) sector
development in Vietnam. While the development of
renewable energy resources in Vietnam is agovernment priority, there has been a lack of clarity
about the role of many organizations in Vietnam
impacting energy development, the relationshipbetween them, and the policies required to foster
energy innovation. An objective of this work was to
identify which Vietnamese stakeholders in the RE
sector would benefit from further policy andinstitutional support. To meet the aggressive
government goals associated with RE innovation, theproject is also focused on identifying relevantorganizations in the sector and understanding how
they interact with each other and as a system.
In April 2023, NISTPASS held a workshop withvarious Vietnamese groups titled “Mapping Sector
Innovation System of Renewable Energy in
Vietnam,” which was attended by HNEI and ONR
personnel. Incorporating inputs from this workshop,
NISTPASS submitted a book titled “Sectoral
Innovation System in Renewable Energy: Case of
Solar and Wind in Vietnam.” This project iscompleted, but HNEI has initiated discussions for asmall, follow-on planning award to continue work inthis area.
Saigon Energy Hub (SEHub) Support
HNEI is collaborating with Ho Chi Minh City’s
Institute for Regional and Urban Studies (IRUS) todevelop a public renewable demonstration andtechnology center to raise the community awarenessof the needs, the feasibility, and the benefits of energy
efficiency and renewable energy. Originally planned
for an outdoor public park venue, the project now
consists of a number of energy efficiency andrenewable energy themed workshops to be conducted
at new facilities located at Ho Chi Minh City Unionof Science and Technology Association’s
Headquarters. A Pre-Feasibility report was submitted

by IRUS, identifying the site, the partners, projected
activities, space utilization, equipment andfurnishings, timeline and budget, and financing
sources.
In September 2023, UH and IRUS personnel met to
discuss progress and the upcoming energy-efficientand renewable energy themed workshops, which willcontinue through July 2024. This work is described in
more detail in Appendix I2.
Provincial Electricity Authority of Thailand (PEA)
Collaboration
HNEI has developed a capacity-building program
focused on topics of renewable energy grid
integration, smart grid technologies, microgrid
assessment and design, and the development ofadvanced EV charging applications for engineersfrom the Provincial Electricity Authority of Thailand(PEA). PEA is a large Thai distribution grid operator
with a service territory spanning all of Thailand,
except for the Bangkok metropolis and two adjoining
provinces (Thailand has 77 total provinces).
Since Spring 2020, HNEI GridSTART has delivered a
training program for PEA select engineers. The
program accommodates two classes of six
engineering interns each year. The program lasts for
twelve weeks and includes 40 hours of lectures andteam-oriented deep immersion in custom “hands-on
mini-project” research, development, and test
endeavors tailored to the learning needs of working
utility engineers focused on energy distribution
systems. Due to COVID-19 travel restrictions, the
PEA intern program experienced delays and shifted
partially to online learning in 2020-2021. In 2022,with the lifting of travel restrictions, two classes of
PEA interns were trained at HNEI in two separate
sessions. Each class was divided into sub-groups
working on various mini-projects, which included
optimizing virtual power plant dispatch and demand
response, improving electric vehicle (EV) energy
consumption estimation, assessing PV hosting
capacity, and designing optimized microgrid systems.
While HNEI GridSTART completed the developmentof the class curriculum and a mini-project researchplan focused on microgrid design and operation,
travel to Hawaiʻi by the incoming 2023 PEA internclasses was unexpectedly suspended due to

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116unforeseen circumstances amid the ongoingrepercussions and political conditions in Thailand
following the contested results of the 2023 national
elections. It is anticipated that the PEA intern training
at HNEI will resume in 2024. This work is describedin more detail in Appendix I3.
Waste-to-Bioenergy Conversion for Community PVBioGrid
With APRESA funding, HNEI contracted Chiang
Mai Rajabhat University, Thailand to conduct anassessment of small biomass systems as a firm power
option in islanded settings. The study included a
resource assessment of potential biomass feedstocksin Thailand, including urban solid wastes andagricultural residues and a technology assessment ofavailable conversion systems. Based on the results, ananaerobic digestion system was selected to integrate
into a grid-isolated community dependent largely on
PV for electricity. The system has been installed at
the University and shake down testing has begun.
Sustainable Aviation Fuel (SAF) Production
APRESA funds have supported Dr. Quang-Vu
Bach’s participation in a research program evaluating
sustainable aviation fuel production systems fortropical environments. Current activities include
evaluation of biomass resources derived from urban
solid waste and their suitability as feedstocks forthermochemical gasification systems. The synthesis
gas product can be subsequently converted with
Fischer-Tropsch synthesis to sustainable aviation
fuel. The aviation industry (civilian and military)
faces significant greenhouse gas challenges due todependence on petroleum jet fuels and limited
opportunity for electrification.
Additionally, APRESA funding contributed to asustainable aviation fuel workshop in Bangkok,
Thailand in May 2023, which was organized by theFederal Aviation Administration (FAA), the U.S.
Trade Development Agency, Energy Technology
Center of Thailand, and HNEI. Its goal was to share
information on SAF developments in the region andto identify barriers to implementing SAF value chains
spanning feedstock production to end use.
Participants from various Asia-Pacific countries
attended, representing civil aviation authorities,
government policymakers, airlines, SAF feedstock
producers, consumers, and technology providers,

university researchers, and airport operators jet fuels
and limited opportunity for electrification.
Support to the USAID Energy Secure Philippines(ESP) Program
In 2019, HNEI GridSTART collaborated with USAID
Clean Power Asia to provide technical and capacity
building support to the Philippines Department ofEnergy (PDOE) for the preparation and presentationof its Department Circular regardingthedevelopment and implementation of net energy
metering (NEM) programs. HNEI GridSTART
continues to support the Philippines’ power sector bydelivering both collaborative (APRESA funded) and
USAID Energy Secure Philippines (ESP) program
funded technical support to the Philippines Energy
Regulatory Commission (ERC), distribution utilities(DUs), and other relevant agencies. Specifically,
HNEI GridSTART has been assisting them indeveloping a comprehensive set of rules for an “offgrid” NEM program tailored to small, rural area grid
systems in the Philippines. HNEI GridSTART is alsocollaborating with USAID ESP and the ERC toestablish a BESS regulatory framework for thePhilippines.
In Summer 2022, HNEI GridSTART submitted
reports and documentation on NEM rules for isolated“off-grid” island systems and a BESS regulatory
framework in the Philippines to USAID ESP and the
ERC. The reports were presented in person in Manila
in August 2022, followed by a workshop with the
USAID ESP and the ERC in September 2022 to draft
BESS regulations for the ERC to promulgate.
In February 2023, HNEI GridSTART conducted asecond in-person writing workshop on the ERC’s
draft BESS regulation. In June 2023, HNEIGridSTART provided capacity building on microgrids
to the ERC and power system resiliency to the DOE.
In November 2023, HNEI GridSTART delivered inperson capacity building on power system resiliency
to the PDOE to assist DUs. HNEI is also working
with USAID ESP to develop and administer a hybridclassroom/hands-on training curriculum to help offgrid DUs optimize NEM uptake, which is planned fordelivery in the first half of 2024. This work is
described in more detail in Appendix I5.

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117

USAID Sustainable Energy for Indonesia’s
Advancing Resilience (SINAR) Program
The USAID’s Sustainable Energy for Indonesia’s
Advancing Resilience (SINAR) program is a fiveyear initiative to support Indonesia’s transition to aclean energy economy. HNEI GridSTART isproviding technical support to the program by helping
to build capacity on a range of topics related toadvanced energy systems, including financing,procurement, planning, and operations. HNEIGridSTART's work is also focused on improving theperformance of energy utilities, such as PT
Perusahaan Listrik Negara (PLN, or State Electricity
Company) and strengthening the institutionalframework and capacity of the energy sector. This
includes helping to develop and implementcompetitive procurement standards, improve cost
recovery mechanisms, and modernize planning andoperating practices.
In February 2022, HNEI GridSTART shared
Hawaiʻi’srenewableenergytransformation
experience with Indonesia’s Directorate General of
Electricity and Ministry of Energy and Mineral
Resources in a three-day webinar. Following thewebinar, in May 2023, HNEI was invited and traveled
to Indonesia and conducted a three-day workshop on
small island grid planning for PLN in Bali, as well asa one-day webinar for the SetjenDEN (the National
Energy Council of Indonesia) in Jakarta. Discussions
with Indonesian stakeholders during that trip have led
to ongoing discussions regarding additional capacity
building in Hawaiʻi, which is planned for 2024. This
project is described in more detail in Appendix I6.
Électricité du Laos (EDL) and Ministry of Energy and
Mines (MEM) Support
HNEI has agreed, pursuant to an October 25, 2021
Letter of Engagement with EDL, to deliver needed
technical capacity building support at EDL’s request
on the following topics: 1) practical guidance forinterconnection of distributed solar PV systems to the
distribution grid; 2) training curriculum on topics
such as voltage regulation and variation, frequency
limits, voltage dips, voltage unbalance, voltage
flicker and harmonics; and 3) standards of practice for
installing and operating underground distribution
cables. With the lifting of COVID-19 travel
restrictions by the Laos government, plans areunderway for HNEI to deliver in-person and remotetraining on these topics starting in 2024.
USAID Southeast Asia’s Smart Power Program(SPP) – LaosA Letter of Collaboration, initiated by Deloitte
Consulting (Deloitte), the prime contractor for the
USAID Southeast Asia Smart Power Program (SPP),
was signed with HNEI on October 27, 2022. The
USAID SPP is a $40 million, five-year initiative withthe goal of mobilizing $2 billion in blended financing
for clean energy infrastructure. The program sets out
to drive economic growth and development ofSoutheast Asia, focusing on creating secure, marketoriented, and environmentally responsible energy
sectors. The ultimate vision is to help the region
achieve its target of net-zero greenhouse gas
emissions by 2050.
Among the initial tasks outlined in the collaborationagreement, HNEI is providing support to Électricité
du Laos (EDL) and the Lao Ministry of Energy and
Mines (MEM) focused on enhancing power system
resilience,
implementing
demand-side
management/demand response (DSM/DR) strategies,
and integrating variable renewable energy (VRE)
resources into their transmission and distribution
systems.
In 2023, HNEI GridSTART delivered updated
Feasibility Study Guidelines for wind, solar, andbiomass energy projects in Laos. GridSTART also
provided an updated Grid Code for Laos thatincorporates interconnection standards for inverterbased resources as well as updated interconnection
standards for PV systems connected at the
distribution level. In addition, HNEI GridSTART
conducted two capacity building sessions for EDL
and MEM staff focusing on the updated Grid Codeand distribution interconnection standards. This work
is described in more detail in Appendix I7.
Production Cost Estimates for Millettia pinnata
Millettia pinnata, also called karanja or pongamia, isindigenous to the Indian subcontinent and Southeast
Asia. This leguminous tree bears seed rich in fatty
acids (27 to 39 wt%) that when harvested can beprocessed into oil, nitrogen-rich meal, andlignocellulosic pod fractions that all can play roles in
improving the resiliency in both food and energy for

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118island communities in tropics. APRESA funds
support an initial cost of production analysis todetermine farm gate prices for harvested seed pods
based on costs to establishment, maintenance, andharvesting costs for pongamia orchards in Hawaiʻi.
This analysis framework can be extended to otherlocations in the tropical Pacific.

Funding Source: Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu;
Leon Roose, lroose@hawaii.edu;
Scott Turn, sturn@hawaii.edu;
Last Updated: November 2023

Energy Systems Regulatory and Technical Support
for Pacific Island Countries
HNEI GridSTART is providing technical andregulatory/policy support to various Pacific Island
Countries (PIC), such as the Republic of Palau(Palau), Cook Islands, Commonwealth of theNorthern Mariana Islands (CNMI), and Republic of
the Marshall Islands (RMI).
In September 2023, HNEI GridSTART hosted two
trainings for PIC representatives in Hawai‘i: a threeday training program for the newly appointed
Director of Palau’s Energy and Water Administration(PEWA) and utility staff on a variety of energy
transition policies and regulations, and a one-day
training program for the members of the Cook
Islands’ power company, Te Aponga Uira (TAU),
including Board members, the Chief Executive
Officer, and the Chief Engineer. Topics included
Hawai‘i’s energy transition, grid modernization,battery energy storage systems, and a case study on
Molokaʻi’s distributed PV integration. Discussions
with TAU are ongoing to define further HNEI support
across a wide range of energy and regulatory needs.
At the Pacific Power Association’s (PPA) 30th Annual
Conference in Saipan, HNEI GridSTART met with a
CNMI’s Commonwealth Utilities Corporation (CUC)
Board member who expressed interest in HNEI’s
support for their renewable integration plans. Followup meetings with CUC will be scheduled to identify
and prioritize areas of support. GridSTART also met
with representatives from RMI’s National Energy
Office during the conference, which requested HNEI
to review and comment on RMI’s new energy
legislation and regulations. Based in part oninteractions with other stakeholders at the PPA
conference, HNEI GridSTART is further engaged in
discussions to support additional projects in Samoa,
Tonga, the Federated States of Micronesia, Nauru,
Kiribati, Tuvalu, and Niue. This work is described in
more detail in Appendix I8.
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119Hawaiʻi Natural Energy Institute Research Highlights
Appendix I: International
I2: Saigon Energy Hub (SEHub) Support

OBJECTIVE AND SIGNIFICANCE: HNEI is
collaborating with Ho Chi Minh City’s Institute for
Regional and Urban Studies (IRUS) to develop apublic renewable demonstration and technology
center to raise the community awareness of the needs,
the feasibility, and the benefits of energy efficiency(EE) and renewable energy (RE). In addition toraising community awareness, the project is intended
to strengthen the role of social media in theengagement of policy makers and the private sector.
This project will comprise two phases: a planning,
design, and construction phase for development of theworkshop platform and an implementation phase
where contractors shall present eight (8) publicly
accessible energy-related workshops through theworkshop platforms.
BACKGROUND: Included among the objectives of the
Hawaiʻi Natural Energy Institute’s Asia PacificRegional Energy System Assessment (APRESA)
award from the Office of Naval Research, is todevelop partnerships with national, regional, or local
jurisdictions, private and public stakeholders,
includinguniversities
and
other
researchorganizations in the Asia-Pacific region to enhance
the reliability, stability, and resilience of the energy
systems.
Under this agreement, HNEI is supporting Ho Chi
Minh City’s local non-governmental organization,
IRUS to design and implement the Saigon Energy
Hub (SEHub), a virtual, publicly accessible,
education platform offering energy-related forums to
the community.
PROJECT STATUS/RESULTS: The SEHub began in
2022 as a conceptual project with IRUS, defining
project benefits and financial requirements in order todevelop a project prospectus for future collaborative
partners, including developers, financial entities, andthe local government.

Science and Technology Association’s Headquarters,
at 224 Dien Bien Phu Street, Vo Thi Sau Ward,
District 3 in the historical centre of Ho Chi Minh City.
IRUS is completing the outfitting two meeting spaces
with the equipment and technologies to present bothonline and offline workshops.

Figure 1. HCM-USTA Building, Ho Chi Minh City.

The workshop series will consist of eight (8) live andonline energy-related workshops. IRUS will develop
and present for approval the eight course topics, thecourse descriptions, length, and structure, timelines,
target audience, anticipated participants, methods foroutreach and marketing, and methods to deliver
online and record workshops to make them publicly
available in the future.
A Pre-Feasibility report was submitted by IRUS,
identifying the site, the partners, projected activities,
space utilization, equipment and furnishings, timelineand budget, and financing sources. In September
2023, UH and IRUS personnel met to discuss
progress and the upcoming energy themed
workshops. The project will continue through July
2024.
Funding Source: Office of Naval ResearchContact: Richard Rocheleau, rochelea@hawaii.edu
Last Updated: November 2023

As the project implementer, IRUS is consolidating a
local public-private partnership to support thedevelopment of the SEHub. Originally planned for an
outdoor public park venue, the project now consistsof a number of energy efficiency and renewableenergy themed workshops to be conducted at new
facilities located at Ho Chi Minh City Union of
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120

Hawaiʻi Natural Energy Institute Research Highlights

Appendix I: International
I3: Provincial Electricity Authority of Thailand (PEA) Collaboration
OBJECTIVE AND SIGNIFICANCE: With funding fromthe U.S. Office of Naval Research (ONR) under the
Asia-Pacific Regional Energy Systems Assessment(APRESA) grant, HNEI’s Grid System Technologies
Advanced Research Team (GridSTART) developed acapacity-building program focused on topics ofrenewable energy grid integration, smart gridtechnologies, microgrid assessment and design, anddevelopment of advanced electric vehicle (EV)charging applications for engineers from theProvincial Electricity Authority of Thailand (PEA).
The PEA is the distribution grid operator with aservice territory spanning all of Thailand, except for
the Bangkok metropolis and two adjoining provinces(Thailand has 77 total provinces).

mini-projects, which included optimizing VPP
dispatch and demand response, improving EV energy
consumption estimation, assessing PV hosting
capacity, and designing optimized microgrid systems.
The program is designed to substantially enhance
PEA engineers’ knowledge of distributed energy
resource technologies, EV applications, andmicrogrids.
In the mini-projects for the 2022 intern classes, PEA
engineers worked on economic dispatch forcustomer-sited PV and battery energy storage
systems, enhancing EV energy consumption
estimation algorithms, determining PV hosting
capacity for distribution circuits, and assessing thefeasibility of prospective microgrid sites in Thailandusing the XENDEE modeling platform. The projects
delivered deep hands-on experience and drew heavily
on HNEI GridSTART’s research, development, andtesting expertise in the areas of distributed energy
resources, advanced EV charging applications, andsmart grid technology.

Figure 1. Sample of the teaching materials.

BACKGROUND: Since Spring 2020, HNEIGridSTART has conducted a training program forselect PEA engineering interns. This programaccommodates two classes of six engineering interns
each year. The program lasts for twelve weeks,
includes 40 hours of classroom-based lectures
tailored to working utility engineers, and is centeredon customized hands-on mini-projects focused onenergy distribution systems. The lectures coversubjects such as renewable energy integration andsmart grid technologies, while the mini-projects
involve tasks such as developing controls for EV
chargers, analyzing PV hosting capacity, studying
virtual power plant (VPP) energy management, andoptimizing microgrid design and operation.
PROJECT STATUS/RESULTS: Due to COVID-19
travel restrictions, the PEA intern program
experienced delays and shifted partially to online
learning in 2020-2021. In 2022, with the lifting oftravel restrictions, two classes of PEA interns weretrained at HNEI in two separate sessions. Each class
was divided into sub-groups working on various

Figure 2. PV hosting capacity simulation on a PEA
distribution feeder.

While the class curriculum and a mini-project focusedon microgrid design and operation were developed
for the incoming 2023 PEA intern classes, the PEA
unexpectedly suspended travel to Hawai‘i due tounforeseen circumstances amid the ongoingrepercussions and political conditions in Thailand
following the contested results of the 2023 national
elections. It is anticipated that the PEA intern training
at HNEI will resume in 2024.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

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121

Hawaiʻi Natural Energy Institute Research Highlights

Appendix I: International
I4: USAID Papua New Guinea Electrification Partnership (PEP) Activity
OBJECTIVE AND SIGNIFICANCE: HNEI GridSTART
is providing technical assistance to the Research
Triangle Institute (RTI), the prime contractor
implementing the United States Agency forInternational Development (USAID) Papua New
Guinea (PNG) Electrification Partnership (PEP)
program. USAID-PEP aims to support PNG’senhanced electric connectivity and its goal ofconnecting 70% of its population to electricity by
2030. By expanding reliable and affordable
electricity, USAID-PEP will help advance inclusive
growth, development, and empowerment incommunities throughout the country.
BACKGROUND: The $57 million USAID-PEP
program was launched in November 2020. HNEIGridSTART is supporting RTI in improving PNG
Power Limited’s (PPL) financial viability,
developing off-grid electrification models, andimproving PNG’s energy regulations. Specifically,
HNEI GridSTART is supporting RTI on an end-to-end
utility transformation of PPL by: 1) improving
competitive procurement and conducting due
diligence on the existing independent power producer
pipeline; 2) developing viable off-grid electrification
models by developing a private sector engagement
strategy; 3) building a portfolio of viable sites;
participating in stakeholder groups; and 4)
demonstrating measurable improvement in PNG’senergy regulator, the National Energy Authority(NEA), by improving the national regulatory
framework for off-grid electrification and engaging
stakeholders to inform and implement enabling
policies and regulations.

Figure 1. PPL’s Main Power Systems, extracted from the
PPL Diagnostic Assessment Report submitted in 2022.

PROJECT STATUS/RESULTS: HNEI GridSTART has
been providing extensive support to the USAID-PEP
program by reviewing the draft PNG Off-Grid
Regulation, evaluating IEC standards for rural
electrification by PNG’s National Institute ofStandards and Industrial Technology (NISIT),
participating in stakeholder meetings, and conducting
training on HOMER software. HNEI GridSTART also
reviewed updates to PNG’s Third-Party Access(TPA) Code, Electricity Industry Regulations, andGrid Code for transmission-level interconnections, aswell as proposing interconnection standards forinverter-based resources connected at the distribution
level.
Subsequently, HNEI prepared and delivered a fourday in-person workshop in November 2022, focusing
on the PNG Grid Code and distributed energy
resource (DER) interconnections, PNG TPA Codeand technical regulations, and public consultation
with NEA, PPL, and independent power producers(IPPs). Based on additional input from RTI (i.e., theWiring Rules), the team provided updates to the four
previously reviewed Electricity Industry Regulations.
Additionally, the team initiated the development ofdraft Distributed Generation Unit (DGU)
Interconnection Standards Technical Requirements
for PNG and reviewed and/or drafted ten District
Energy Plan Assistance reports in support of rural
electrification objectives.
In May 2023, HNEI GridSTART collaborated with
USAID-PEP on the conceptual formulation of an offgrid code for PNG. In October 2023, HNEI also
provided a briefing on the Grid Code and TPA Codefor presentation to the NEA Board of Directors,
including a newly added section on Distributed
Generating Unit Interconnection Standards TechnicalRequirements.

Figure 2. Sample slides from the four-day workshop in
November 2022.

Funding Source: USAID-PEP
Contact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

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Appendix I: International
I5: Support to the USAID Energy Secure Philippines (ESP) Program
OBJECTIVE AND SIGNIFICANCE: HNEI GridSTART
is delivering technical support to the USAID-funded
Energy Secure Philippines (ESP) Program, thePhilippines Energy Regulatory Commission (ERC),
and the Philippines Department of Energy (PDOE) intheir mission to advance inclusive economic growth
and resilient energy sector development. This support
includes the establishment of net energy metering(NEM) rules for numerous small island grid systems
and the development of a regulatory framework forbattery energy storage systems (BESS) adoption in
the Philippines.
BACKGROUND: In 2019, HNEI GridSTART
collaborated with USAID Clean Power Asia toprovide technical and capacity building support to the
PDOE for the preparation and presentation of its
Department Circular (DC) titled “Promulgating
Policies to Enhance Customers’ Participation in thePhilippines’ Net-Metering Framework.”
HNEI GridSTART continues to support thePhilippines’ power sector by delivering bothcollaborative (APRESA-funded) and USAID ESPfunded technical support to the ERC, PDOE,
distribution utilities (DUs), and other Philippine
energy industry stakeholders. Specifically, HNEIGridSTART has assisted in developing acomprehensive set of rules for a NEM program, as
well as a mandated regulatory framework for BESSin the Philippines. The BESS framework includes:
streamlined rules for BESS interconnection,
guidelines for BESS technical codes and standards,
mechanisms for cost recovery related to utility-owned
BESS, and third-party-owned BESS delivering
ancillary services. This work is assisting the ERC infulfilling its mandate set by the PDOE.
PROJECT STATUS/RESULTS: In the summer of 2022,
HNEI
GridSTART
submitted
reportsanddocumentation on NEM rules for isolated “off-grid”
island systems and a BESS regulatory framework in
the Philippines to USAID ESP and the ERC. These
reports were presented in person in Manila in August2022 and a workshop with the USAID ESP and the
ERC followed in September 2022 to draft BESS
regulations for ERC promulgation. In February 2023,
HNEI GridSTART conducted a second in-person
writing workshop on the ERC’s draft BESS
regulation.

Figure 1. HNEI’s Philippines BESS Regulation DraftingWorkshop #2 in Pasig City in February 2023.

In June 2023, HNEI GridSTART delivered in-person
capacity building on microgrids to the ERC and on
power system resiliency to the PDOE. Following
these presentations, HNEI GridSTART participated as
an online presenter in the Philippines’ 2023 Energy
Resiliency Forum at the PDOE’s request.

Figure 2. HNEI’s meeting with the PDOE in June 2023.

In November 2023, HNEI GridSTART delivered twodays of in-person capacity building activities onenergy storage systems (ESS) to the PDOE, aimed toassist DUs by: 1) providing a better understanding of
the costs and benefits of ESS; 2) building an
understandingofBESS
behind-the-meter
applications; 3) helping policymakers and regulators
to address BESS-related policy and regulatory gaps;
and 4) assessing the need to enhance the existing
institutional approach to promote and utilize BESS in
the Philippines.
HNEI GridSTART is also working with USAID ESP
to develop and administer a hybrid classroom/handson training curriculum aimed at helping off-grid DUs
optimize NEM uptake, which is currently planned to
be delivered in the first half of 2024.
Funding Source: USAID ESP Program; Office ofNaval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

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Appendix I: International
I6: USAID Sustainable Energy for Indonesia’s Advancing Resilience Program
OBJECTIVE AND SIGNIFICANCE: In September
2021, HNEI GridSTART was contracted by Tetra
Tech ES to provide technical support for USAID’s
Sustainable Energy for Indonesia’s Advancing
Resilience (SINAR) program. The SINAR programaims to advance Indonesia’s development goals in
expanding reliable and equitable energy services
necessary for sustainable development and inclusive
economic growth. SINAR program objectives
include: 1) accelerating deployment of advancedenergy; 2) improving performance of energy utilities;3) adopting transparent and best value procurement;
and 4) strengthening the institutional framework andcapacity of the energy sector.
BACKGROUND: Although Indonesia has abundant
renewable energy (RE) resources, they are not being
utilized to their full potential. One of the obstacles toaccelerating the adoption of RE resources is thelimited experience of key energy stakeholders onproper and prudent RE planning for energy transitionin accordance with local conditions and current
energy policies. In an effort to help the Governmentof Indonesia increase the use of RE, in line with its
National Energy Policy and Nationally Determined
Contributions (NDC) under the Paris Agreement,
USAID SINAR identified a need for Indonesia’s
Ministry of Energy and Mineral Resources (MEMR)
and PT Perusahaan Listrik Negara (PLN or ‘StateElectricity Company’) to have a clear strategy,
standard framework, and program roadmap for the
successful energy transition toward net zero
emissions.
PROJECT STATUS/RESULTS: HNEI GridSTART is
supporting the USAID SINAR program by providing
capacity building on: 1) advanced energy systems
finance and development, 2) utility cost recovery andmodernization, 3) competitive procurement anddomestic resource utilization, and 4) stakeholder
coordination and policy improvement.

transformation and lessons learned garner greatinterest and attention not only from Indonesia but also
from numerous countries in the Asia-Pacific region,
due to their similar geographical and climaticcharacteristics.
Following the webinar, in May 2023, HNEIGridSTART was invited and traveled to Indonesia to
conduct a three-day workshop on small island gridplanning for PLN in Bali and a one-day webinar for
the Setjen DEN (the National Energy Council ofIndonesia) in Jakarta. Discussions with Indonesian
stakeholders during that trip have led to ongoingscoping discussions for additional capacity building
located in Hawaiʻi, which is planned for 2024.

Figure 1. HNEI GridSTART participants in a focus group
discussion in Indonesia in May 2023.

Funding Source: USAID SINAR Program; Office ofNaval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

In February 2022, HNEI GridSTART presented athree-day webinar to Indonesia’s Directorate Generalof Electricity (DGE) and MEMR on Hawaiʻi’srenewable energy transformation, lessons learned
from incorporating increasing levels of RE, andtechnical issues posed by high renewable penetrations
in modern power systems. HNEI’s deep knowledge
and understanding of Hawaiʻi’s successful energy
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

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Hawaiʻi Natural Energy Institute Research Highlights
Appendix I: International
I7: USAID Southeast Asia’s Smart Power Program – Laos

OBJECTIVE AND SIGNIFICANCE: A Letter ofCollaboration, initiated by Deloitte Consulting(Deloitte), the prime contractor for the USAID
Southeast Asia Smart Power Program (SPP), wassigned with HNEI on October 27, 2022. The USAID
SPP is a $40 million, five-year initiative with the goalof mobilizing $2 billion in blended financing for clean
energy infrastructure. The program sets out to drive
economic growth and development in Southeast Asia,
focusing on creating secure, market-oriented, andenvironmentally responsible energy sectors. The
ultimate vision is to help the region achieve its targetof net-zero greenhouse gas emissions by 2050.
Among the initial tasks outlined in the collaborationagreement, HNEI is providing support to Électricité
du Laos (EDL) and the Lao Ministry of Energy and
Mines (MEM) focused on enhancing power system
resilience,
implementing
demand-side
management/demand response (DSM/DR) strategies,
and integrating variable renewable energy (VRE)
resources into their transmission and distribution
systems.

initiatives, accelerated cross-border interconnection
and power trade, and established training centers forenergy practitioners to develop solutions that enable
Southeast Asian countries to become self-reliant andachieve their sustainable development aspirations.
Following on the accomplishments of USAID CPA,
USAID SPP plans to implement numerous newactivities, such as establishing a Center for
Competitive Procurement (CCP), conducting aresiliency assessment of ASEAN power utilities, andundertaking capacity development efforts to support
them. Toward that end, Deloitte and HNEIGridSTART anticipate collaboration opportunities toleverage the comparative advantages of the USAID
SPP and HNEI teams across all of SPP’s task areas,
including utility modernization, DSM/DR, energy
innovation and emerging trends, competitive
procurement, power trade, and grid integration.
PROJECT STATUS/RESULTS: In 2023, HNEIGridSTART delivered updated Feasibility Study
Guidelines for wind, solar, and biomass energy
projects in Laos. The team also provided an updated
Grid Code for Laos that incorporates interconnection
standards for inverter-based resources as well as
updated interconnection standards for PV systems
connected at the distribution level. Additionally,
HNEI conducted two capacity building sessions inJune and October 2023 for EDL and MEM staff,
focusing on the updated Grid Code and distribution
interconnection standards.

Figure 1. Abstract of Laos map.

BACKGROUND: USAID SPP is the regional successor
program to USAID’s earlier Clean Power Asia (CPA)
program, under which HNEI GridSTART provided
both collaborative (APRESA-funded) and CPAfunded support over the prior four years. Its primarygoals included: 1) expanding energy capacity throughthe deployment of advanced energy systems, 2)
increasing clean energy investments in the regionalenergy sector, and 3) enhancing regional energy
trade. This was to ensure secure, market-driven
energy sectors that support sustained economic
growth. The program leveraged bilateral andmultilateral partnerships, supported regional

Figure 2. Capacity building session in Vientiane, Laos inJune 2023.

Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

125

Hawaiʻi Natural Energy Institute Research Highlights

Appendix I: International
I8: Energy Systems Regulatory and Technical Support for Pacific Island Countries
OBJECTIVE AND SIGNIFICANCE: Through funding
under the APRESA grant from the U.S. Office ofNaval Research, HNEI GridSTART is providing
technical and regulatory/policy support to various
Pacific Island Countries (PIC), including theRepublic of Palau (“Palau”), Cook Islands,
Commonwealth of the Northern Mariana Islands(CNMI), and Republic of the Marshall Islands (RMI).
BACKGROUND: HNEI’s support for the various PICs
are as follows:• Palau: HNEI GridSTART is supporting Palau’s
Energy and Water Administration (PEWA) indeveloping key energy regulatory framework
elements, modeling the national electric grid tofacilitate increasing penetration of variable
renewable energy, and developing technical gridinterconnection requirements for new renewablegeneration.
• Cook Islands: The Cook Islands Economic
Development Strategy includes a national
renewable energy target of 60% by 2030, with anational commitment to a 100% renewableenergy future. In support of these goals, HNEI is
assisting the Cook Islands’ power company, Te
Aponga Uira (TAU), with capacity building on a
range of energy transition topics.
• CNMI: Although efforts have been made tointegrate renewable energy into its power grid,
CNMI still heavily depends on imported fossil
fuels for its energy generation. HNEI GridSTART
is providing technical support to CNMI through acollaboration with Commonwealth Utilities
Corporation (CUC), a government-owned utility
company.
• RMI: As a country highly vulnerable to climatechange due to its heavy dependence on imported
fossil fuels for energy generation, RMI isdeveloping an energy law and supporting
regulations that must be promulgated to
implement RMI’s 2018 energy roadmap.

Chief Engineer. Topics covered during the training
sessions included: 1) Hawai‘i’s energy transition, 2)
grid modernization, 3) battery energy storage
systems, and 4) a case study on the distributed PV
integration on Molokaʻi. Discussions are ongoingwith TAU to further define HNEI support across awide range of energy and regulatory needs.
At the Pacific Power Association’s (PPA) 30th Annual
Conference in Saipan, HNEI GridSTART met with a
CUC Board member who expressed interest in HNEI
support for their renewable integration plans. Followup meetings with CUC will be scheduled to identify
and prioritize areas of support.
HNEI also met with representatives from RMI’s
National Energy Office (NEO) during the conference,
which requested a review of and comments on RMI’s
new energy legislation and regulations. Further
discussions with NEO will be held to finalize thescope of support.
Based in part on interactions with other stakeholders
at the PPA conference, HNEI GridSTART is also
engaged in discussions with regional stakeholders to
support additional energy transition and renewableenergy project needs in Samoa, Tonga, the Federated
States of Micronesia, Nauru, Kiribati, Tuvalu, andNiue.
Funding Source: Office of Naval ResearchContact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

PROJECT STATUS/RESULTS: In September 2023,
HNEI GridSTART hosted two trainings for PIC
representatives in Hawai‘i: 1) a three-day training
program for the newly appointed Director of PEWA
and Palau electric utility staff on a variety of energy
transition policies and regulations and 2) a one-day
training program for members of TAU, including
Board members, the Chief Executive Officer, and the
Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

126

Hawaiʻi Natural Energy Institute Research Highlights
Appendix I: International
I9: Energy Security and Resilience in the Caribbean Islands

OBJECTIVE AND SIGNIFICANCE: In February 2023,
HNEI was contracted by Deloitte & Touche LLP(“Deloitte”) to deliver technical assistance for the
U.S.-Caribbean Partnership to Address Climate
Change 2030 (PACC 2030), a U.S. Department ofState (DOS) funded initiative. PACC 2030
establishes a framework aimed at enhancing U.S.
cooperation with Caribbean countries to bolster
climate adaptation, energy security, and resilience of
critical infrastructure and local economies in the faceof the climate crisis. Deloitte’s role within PACC
2030 is to enhance energy security and resilience in
the Caribbean through essential technical support inthree key areas:
1. Supporting geothermal development in the
Dominican Republic;
2. Building regulatory capacity in the realms ofclean energy and utility oversight; and3. Strengthening the technical capabilities ofelectric utilities and energy ministries in the
integration of renewable energy, electric
mobility (e-mobility), and power system
resilience.

Organization of Caribbean Utility Regulators(OOCUR);• Facilitating regional regulatory in-person training
sessions for CARILEC and OOCUR;• Providing support for virtual training on ETAP
Software for Barbados; and• Preparing technical reports on a variety of topics
for the following entities:
 Jamaica Office of Utilities Regulation;
 St. Kitts Electricity Company;
 Trinidad and Tobago; and Jamaica Public Service.
The final report entitled “Recommendations on Grid
Codes and Reliability Benchmarks and Criteria” wassubmitted to the St. Kitts Electricity Company on
August 4, 2023. A preliminary draft of a report
entitled “Climate Adaptation and Resilience in
Trinidad and Tobago” was also submitted to Deloitte
on October 9, 2023.

To achieve these objectives, HNEI GridSTART isproviding vital technical support on behalf of
Deloitte.
BACKGROUND: The Caribbean faces the highest
dependency on imported oil for power generation andthe highest average electricity prices in the Western
Hemisphere. This situation results in expensive andunreliable electricity, making the region vulnerable toglobal supply shocks. Following years of energy
engagement under the Caribbean Energy Security
Initiative (CESI), the Biden-Harris Administration
announced PACC 2030 in June 2022 during the U.S.hosted Summit of the Americas. PACC 2030 serves
as the comprehensive framework through which all
U.S. government climate and clean energy efforts will
be implemented in the region.
PROJECT STATUS/RESULTS: HNEI GridSTART isproviding analytical and advisory services for various
activities and deliverables outlined in its contract with
Deloitte. These include:• Conducting regional regulatory virtual training
sessions for the Caribbean Electric Utility
Services Corporation (CARILEC) and the

Figure 1. Report submitted to the St. Kitts Electricity
Company.

Additional reports for Trinidad and Tobago andJamaica Power Service are in progress. Virtual andin-person training sessions are currently being
planned and are scheduled for the first and second
quarters of 2024.
Funding Source: U.S. Department of State
Contact: Leon Roose, lroose@hawaii.edu
Last Updated: November 2023

Hawai‘i Natural Energy Institute | School of Ocean & Earth Science & Technology
University of Hawaiʻi at Mānoa, 1680 East-West Road, POST 109 • Honolulu, HI 96822
Phone: (808) 956-8890 • Fax: (808) 956-2336 • www.hnei.hawaii.edu

127