NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Contract No. DE-AC36-08GO28308

Targeting Net Zero Energy at 

Marine Corps Base Kaneohe 

Bay, Hawaii: Assessment and 

Recommendations 

K. Burman, A. Kandt, L. Lisell, S. Booth, 

A. Walker, J. Roberts and J. Falcey

Technical Report

NREL/ TP-7A40-52897

November 2011
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401

303-275-3000 • www.nrel.gov

Contract No. DE-AC36-08GO28308

Targeting Net Zero Energy at 

Marine Corps Base Kaneohe 

Bay, Hawaii: Assessment and 

Recommendations 

K. Burman, A. Kandt, L. Lisell, S. Booth, 

A. Walker, J. Roberts and J. Falcey

Prepared under Task No. IDHW.9180 

Technical Report

NREL/ TP-7A40-52897

November 2011
NOTICE

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i

Contacts

National Renewable Energy Laboratory

Kari Burman

National Renewable Energy Laboratory

Kari.Burman@nrel.gov

303-384-7558

Alicen Kandt

National Renewable Energy Laboratory

Alicen. Kandt@nrel.gov

MCBH Kaneohe Bay, HI

William H. Nutting, PE, RA

Energy Manager/Utilities Engineer

Phone: (808) 257-1667

Email: William.nutting@usmc.mil

John Dunbar

Resource Efficiency Manager

Phone: (808) 257-1537

Email: John.r.dunbar1.ctr@usmc.mil

Ronald Hochbrueckner

Facilities

Phone: (808) 257-6883

Email: ronald.hochbrueckner@usmc.mil
ii

Acknowledgements

This work is sponsored by the U.S. Department of Energy (DOE) in partnership with the state of 

Hawaii and the Hawaii Clean Energy Initiative (HCEI).

The National Renewable Energy Laboratory (NREL) would like to thank William H. Nutting,

PE, RA (Energy Manager/Utilities Engineer); John Dunbar, PE, CEM (Resource Efficiency 

Manager) and Ronald P. Hochbrueckner (Electrical Engineer) and the energy team at Marine 

Corp Base Hawaii-Kaneohe Bay for their invaluable assistance in support of this work.
iii

Abbreviations and Acronyms

AC Alternating current

AFV Alternative fuel vehicle

AHU Air handling unit

ARRA American Recovery and Reinvestment Act

Btu British thermal unit

C&D Construction and demolition

CHP Combined heat and power

CNG Compressed natural gas

CO2 Carbon dioxide

COE Cost of energy

CSP Concentrating solar power

CSU Colorado Springs Utilities

CV Constant volume

DDC Direct digital controls

DG Distributed generation

DHW Domestic hot water

DOD U.S. Department of Defense

DOE U.S. Department of Energy

DX Direct expansion

EE Energy efficiency

EEAP Energy Engineering Analysis Program

ECIP Energy Conservation Investment Program

ECM Energy conservation measure

EISA Energy Independence and Security Act of 2007

E.O. Executive order

EPA U.S. Environmental Protection Agency

ESCO Energy service company

ESPC Energy savings performance contract

EUI Energy use intensity

FAR Federal Acquisition Regulation

FEMP Federal Energy Management Program

FFRDC Federally Funded Research and Development Center

FFV Flex fuel vehicle

FRREC Front Range Renewable Energy Consortium

ft2 square foot

GHG Greenhouse gas

GIS Geographic information system

GSA U.S. General Services Administration

GSHP Ground Source Heat Pump

HCEI Hawaii Clean Energy Initiative

HECO Hawaii Electric Company

HEV Hybrid electric vehicle

HQ Headquarters

HVAC Heating, ventilating, and air conditioning

KCF Thousand cubic feet
iv

kg kilogram

kVA kilovolt-ampere

kWh kilowatt-hour

LCOE Levelized cost of energy

LED Light-emitting diode

MCBH Marine Corps Base Hawaii

MCCS Marine Corps Community Service

MMBtu Million British thermal units

MSW Municipal solid waste

MVA Mega Volt-Amp

MW Megawatt

MWe Megawatt-electrical

MWh Megawatt-hour

NEPA National Environmental Policy Act

NETL National Energy Technology Laboratory

NEV Neighborhood electric vehicle

NREL National Renewable Energy Laboratory

NZEI Net zero energy installation

O&M Operations and maintenance

PEM Proton exchange membrane

PNNL Pacific Northwest National Laboratory

PPA Power purchase agreement

PSD Potential for Significant Deterioration

PV Photovoltaics

RDF Refuse-derived fuel

REC Renewable energy certificate

SAM Solar Advisory Model

SNL Sandia National Laboratory

SUV Sport utility vehicle

TES Thermal energy storage

PACOM U.S. Pacific Command

VAV Variable air volume

VFD Variable frequency drive

W watt

WTE Waste to energy

WTG Wind turbine generator

ZEB Zero energy building
v

Executive Summary

The U.S. Department of Defense (DOD) has long recognized the strategic importance of energy 

to its mission, and is working to reduce energy consumption, as well as enhance energy security 

by drawing on local clean energy sources. A recent Defense Science Board report stated that 

critical military missions are at a high risk of failure in the event of an electric grid failure.1 The 

development of on-site renewable energy supplies can reduce this risk, and may become an 

increasingly important strategic concern. Renewable energy can also contribute to improved 

security of the energy supply and of the site, decreased or more predictable energy costs, and 

responsiveness to energy-related Federal or DOD mandates.

DOD’s U.S. Pacific Command has partnered with the U.S. Department of Energy’s (DOE) 

National Renewable Energy Laboratory (NREL) to assess opportunities for increasing energy 

security through renewable energy and energy efficiency in Hawaii installations. On the basis of 

the installation’s strong history of energy advocacy and extensive track record of successful 

energy projects, NREL selected Marine Corps Base Hawaii (MCBH), Kaneohe Bay to receive 

technical support for net zero energy assessment and planning funded through the Hawaii Clean 

Energy Initiative (HCEI). NREL performed a comprehensive assessment to appraise the 

potential of MCBH Kaneohe Bay to achieve net zero energy status through energy efficiency, 

renewable energy, and electric vehicle integration. This report summarizes the results of the 

assessment and provides energy recommendations.

Defining a Net Zero Energy Installation

This report defines a net zero energy installation (NZEI) as follows:

A net zero military installation produces as much energy on-site from renewable 

energy generation, or through the on-site use of renewable fuels, as it consumes in 

its buildings, facilities, and fleet vehicles.

Net zero energy is a concept of energy self-sufficiency based on minimizing demand and using

local renewable energy resources. A complete net zero solution considers all uses of energy 

within an installation for buildings, transportation, community infrastructure, and industry. 

NREL’s net zero energy assessment for MCBH Kaneohe Bay focused on five areas: 

1. An energy baseline

2. Energy efficiency improvements

3. Renewable energy potential

4. Electrical systems analysis

5. Transportation fuel use analysis

Figure 1 shows the phased progression from a typical installation or community, to an 

installation that has a reduced energy load, to a renewably powered installation.

 1 More Fight Less Fuel, Defense Science Board Report. February 2008.

www.acq.osd.mil/dsb/reports/ADA477619.pdf. Accessed May 2010.
vi

Figure 1. Net zero energy concept

MCBH Kaneohe Bay’s Energy Baseline

The first step in a net zero energy assessment is to determine an energy baseline. The baseline

provides an analysis of current energy consumption on base. It gives planners and managers a 

metric to measure progress against. MCBH Kaneohe Bay’s energy baseline includes all energy 

use in buildings, facilities, and fleet vehicles on the main base, excluding housing, which is 

privatized. 

Table 1. MCBH Kaneohe Bay Energy Baseline 

Energy Source 2009 Energy Use

Site Energy 

(Variable units)

Site Energy 

(MMBtu)

Source Energy 

(MMBtu)

Buildings and Facilities

Electricity 107,088,800 kWh 365,387 1,432,317

Propane 206,900 gallons 18,890 21,724

Total Building Energy Use 384,277 1,454,040

Fleet Fuel

Gasoline 181,802 gallons 9,334 10,734

Diesel 93,967gallons 13,860 15,939

Total Fleet Energy Use 23,194 26,673

Total MCBH Kaneohe Bay Energy Use 407,471 1,480,713

Energy Efficiency

The second step in a net zero energy assessment is to evaluate the potential for reductions in 

energy use through improvements in energy efficiency. Through discussion with base personnel, 

analysis of previous energy audits, and modeling of typical buildings, NREL estimated the

Typical 

Community

Option 0

Energy Efficiency 

and Energy 

Demand Reduction

Energy Load ($ or btu or CO2)

buildings

vehicles

industry

Maximize 

efficiency, 

minimize 

demand

Renewable 

Option 1

Renewable 

Option 2

Renewable 

Option 3

Some combination 

of options 1, 2 & 3 

meet remaining load
vii

energy efficiency savings potential of the base. Table 2 summarizes the potential energy savings 

at MCBH Kaneohe Bay, which totals 17.03% electrical load reduction, 6.62% propane load 

reduction, and 16.5 % overall energy reduction. 

Table 2. Energy Efficiency Savings Potential

Measure Savings (% of fuel type) MMBtu 

Equivalent 

Savings

% Total Site 

Savings

Specific Base Facilities

Commissary (32% reduction) MWh 1,401 2.4% 4,780 2.1%

Barracks (40% reduction) MWh 7,497 12.8% 25,587 11.4%

Offices (43% reduction) MWh 3,215 5.5% 10,972 4.9%

Gym (52% reduction) MWh 467 0.8% 1,593 0.7%

Mess Hall (40% reduction) MWh 1,310 2.2% 4,470 2.0%

Base Wide ECMs

Retro-commissioning MWh 2,023 3.5% 6,904 3.1%

Lighting Occupancy Sensors MWh 935 1.6% 3,190 1.4%

Computer Energy Mgmt MWh 1,387 2.4% 4,732 2.1%

Water Heater Boilers MMBtu 1,251 4.8% 1,251 0.6%

Total

Electricity MWh 18,233 17.03% 62,211 15.9%

Propane MMBtu 1,251 6.62% 1,251 0.6%

Total 

MMBtu

63,462 16.5%

Renewable Energy Analysis

After assessing energy use reduction opportunities at MCBH Kaneohe Bay, NREL evaluated the 

potential for renewable energy generation to meet energy needs that would remain after any 

energy efficiency improvements were implemented. The most promising technologies for 

implementation include solar hot water, solar photovoltaics, and wind. Implementation of these 

projects would provide 100% of electrical energy and 59% of thermal energy from renewable 

sources at MCBH Kaneohe Bay. A summary of the technologies and their savings can be seen in 

Table 3 below.

Table 3. Renewable Energy Technologies: Potential Energy Savings and Payback Period

Project Name Size Savings Source Btu Savings

MMBtu

% of Total 

MMBtu

PV 10 MW 15,432,643 kWh 206,412 14%

Wind Turbines 28.5 MW 92,879,232 kWh 1,242,263 86%

Solar Hot Water 257,509 ft2 11,239 MMBtu 12,925 59%

Daylighting 99,140 ft2 2,092,540 kWh 27,988 2%

Totals 161%
viii

Transportation

The analysis evaluated options for reducing transportation energy use at MCBH Kaneohe Bay, 

including:

• Track fleet fuel use: Tracking allows better management of fuel use and fuel savings 

opportunities. 

• Right-size the fleet: Reduce the total number of vehicles in the fleet and allocate 

savings to other fleet needs.

• Switch to alternative fuel vehicles: MCBH Kaneohe Bay is moving quickly to 

incorporate alternative fuel vehicles in its fleet. MCBH Kaneohe Bay recently 

installed E85 and B20 refueling pumps. If MCBH Kaneohe Bay replaced half of the 

gasoline vehicles with flex fuel vehicles (FFV) that run on E85, and if personnel 

consistently fueled them with E85, this would displace nearly 154,532 gallons of 

gasoline consumption per year. If biodiesel were used consistently in the diesel 

vehicle fleet, MCBH Kaneohe Bay could displace another 93,967 gallons of 

petroleum per year. MCBH Kaneohe Bay should always use E85 in FFVs and B20 

biodiesel for diesel vehicles. 

• Hybrid electric vehicles (HEVs) and electric vehicles (EVs): HEVs are also being 

introduced into the MCBH Kaneohe Bay fleet to reduce their fuel use. The fleet 

manager recently mentioned that there are around 100 neighborhood electric vehicles 

that they operate.

• Hydrogen fuel cell vehicles: NREL understands that MCBH- Kaneohe Bay is 

converting some of their fleet to new hydrogen fueled vehicles. They are also 

procuring electrolysis equipment to produce hydrogen on site. The hydrogen vehicle 

fleet is presently 3 sedans that use ~4 kg of hydrogen per tank and 12 kg/week. The 

electrolysis equipment produces 1 kg/ hr or 168 kg of hydrogen per week. An 

additional 13 sedans could be purchased to replace gasoline vehicles.

Implementation

MCBH Kaneohe Bay has several options for implementing energy projects, including energy 

savings performance contracts (ESPCs), utility energy services contracts (UESCs), power 

purchase agreements (PPAs), and appropriated funds. Government-owned projects funded 

through appropriations reduce contractor financing and markup fees, but require up-front capital 

and would prevent MCBH Kaneohe Bay from receiving federal tax incentives. Governmentowned projects would also place an operations and maintenance (O&M) burden on MCBH 

Kaneohe Bay. By contrast, privately-owned projects would allow MCBH Kaneohe Bay to 

implement renewables without any upfront capital, and with reduced O&M responsibility. 

Privately-owned projects would also allow MCBH Kaneohe Bay to take advantage of federal tax 

credits, although some of the money gained in tax credits will go toward contractor financing and 

mark-up fees. 

Federal energy projects require funding to generate results. Carefully matching available 

financing mechanisms with specific project needs can make the difference between a stalled, 
ix

unfunded project and a successful project, generating energy and cost savings. FEMP supports 

federal agencies in identifying, obtaining, and implementing alternative financing to fund energy 

projects.

For assistance with ESPCs, contact:

Scott Wolf

6848 Cooper Point Road NW

Olympia, WA 98502

Phone: 360-866-9163

Fax: 360-866-9683

scott.wolf@ee.doe.gov

For UESCs, contact:

David McAndrew

Federal Energy Management Program

202-586-7722

david.mcandrew@ee.doe.gov

Karen Thomas

National Renewable Energy Laboratory

202-488-2223

karen_thomas@nrel.gov

For PPAs, contact:

Tracy Logan

Federal Energy Management Program

202-586-9973

tracy.logan@ee.doe.gov

Chandra Shah

National Renewable Energy Laboratory

303-384-7557

chandra.shah@nrel.gov

For more information about alternative financing, visit the FEMP Financing Mechanisms Web 

page at www.femp.energy.gov/financing/mechanisms.html. 

Conclusion

The analysis conducted by NREL shows that MCBH Kaneohe Bay has the potential to make 

significant progress toward becoming a net zero installation. If the identified energy projects and 

savings measures are implemented, then a 96% site Btu reduction and a 99% source Btu 

reduction will be achieved by the base. Using excess wind and solar energy to produce hydrogen

for a fleet and fuel cells could significantly reduce their energy use, and could bring the MCBH 

Kaneohe Bay to net zero. Further analysis with an environmental impact and interconnection 

study will need to be completed. By achieving this status, the base will set an example for other 

military installations, provide environmental benefits, reduce costs, increase energy security, and 

exceed its goals and mandates. 
x

Table of Contents

Contacts............................................................................................................................................ i

Acknowledgements......................................................................................................................... ii

Executive Summary........................................................................................................................ v

Table of Contents............................................................................................................................ x

1 Introduction ............................................................................................................................. 1

1.1 Overview of the DOD Energy Context..................................................................... 1

1.2 Energy Strategies for DOD Installations: Key Considerations................................. 2

1.3 NZEI Concept ........................................................................................................... 3

1.4 Assessment Approach............................................................................................... 6

2 MCBH Kaneohe Bay Energy Baseline ................................................................................... 8

2.1 Overview................................................................................................................... 8

2.2 Site Description......................................................................................................... 8

2.3 MCBH Kaneohe Bay Boundary ............................................................................... 8

2.4 Total Consumption Breakdown ................................................................................ 9

2.5 The Electrical Baseline ........................................................................................... 10

2.6 Propane Baseline..................................................................................................... 12

2.7 Transportation Baseline ......................................................................................... 12

2.8 Utility Costs............................................................................................................ 13

3 Reducing Energy Demand by Engaging People.................................................................... 14

4 Energy Efficiency Assessment .............................................................................................. 16

4.1 Overview................................................................................................................. 16

4.2 Summary of Proposed Energy Efficiency Projects................................................. 16

4.3 Base Wide Conservation Measures ........................................................................ 17

4.4 Privatized Housing.................................................................................................. 20

5 Additional Load Reduction and Renewable Energy Projects ............................................... 22

5.1 Overview................................................................................................................. 22

5.2 Renewable Energy Resource Assessment .............................................................. 22

5.3 Renewable Energy Optimization ............................................................................ 23

5.4 Solar Hot Water ...................................................................................................... 24

5.5 Daylighting ............................................................................................................. 25

5.6 Photovoltaic ............................................................................................................ 27

5.7 Concentrating Solar Power ..................................................................................... 28

5.8 Wind Turbines ........................................................................................................ 29
xi

5.9 Fuel Cell.................................................................................................................. 31

5.10 Landfill Gas ............................................................................................................ 34

5.11 Anaerobic Digestion ............................................................................................... 34

5.12 Hydropower/Ocean Wave Energy .......................................................................... 35

5.13 Hybrid System Optimization .................................................................................. 35

6 Transportation Assessment.................................................................................................... 40

6.1 Analysis................................................................................................................... 40

6.2 Additional Strategies to Reduce Load and Footprint.............................................. 42

7 Electrical Systems Assessment and Recommendation.......................................................... 45

7.1 Electrical Distribution System Overview ............................................................... 45

7.2 Impact Analysis of Distributed Generation ............................................................ 46

7.3 Interconnection ....................................................................................................... 46

8 Net Zero Energy Potential ..................................................................................................... 49

8.1 MCBH Kaneohe Bay Projects................................................................................ 49

8.2 Recommended Additional Energy Projects............................................................ 49

8.3 Net Zero Energy Potential ...................................................................................... 50

9 Implementation: Project Planning and Financial Assessment............................................... 51

9.1 Implementation Options.......................................................................................... 51

9.2 Financial Analysis................................................................................................... 55

10 Conclusion .............................................................................................................. 60

Appendix A. Renewable Energy Resource & Environmental Maps............................................ 61

Appendix B. Specific Energy Efficiency measures...................................................................... 68

Appendix C. Solar PV Projects Identified by MCBH Kaneohe Bay............................................ 76

Appendix D: Wind Resource & Turbine Placement..................................................................... 83

Appendix E: Distribution Feeder Capacity and Load................................................................... 88
xii

List of Figures

Figure 1. Net zero energy concept ................................................................................................. vi

Figure 2. DOD Energy Use Breakdown ......................................................................................... 2

Figure 3. Net Zero Energy Concept................................................................................................ 4

Figure 4. MCBH Properties............................................................................................................ 8

Figure 5. Land use zones ................................................................................................................ 9

Figure 6: Typical daily load profile .............................................................................................. 11

Figure 7: Annual load profile........................................................................................................ 11

Figure 8. Fuel use at MCBH Kaneohe Bay 2009 ......................................................................... 12

Figure 9. Hawaii Electric Cost versus the Price of Oil................................................................ 13

Figure 10. Typical ‘small office’ wall switch sensor application and coverage........................... 20

Figure 11. Typical 'open space' ceiling mounted sensor application and coverage...................... 20

Figure 12. Direct SHW system..................................................................................................... 24

Figure 13. Daylighting applicable to the MCBH Kaneohe Bay site............................................. 26

Figure 14. Depiction of major components of grid-connected PV system................................... 27

Figure 15. Vergnet 275 kW wind turbine (2 blades) .................................................................... 30

Figure 16. Cost curve for Wind Technology ................................................................................ 30

Figure 17. PowerBuoy .................................................................................................................. 35

Figure 18. Monthly average electric production........................................................................... 37

Figure 19. Monthly average electric production........................................................................... 39

Figure 20: MCBH Kaneohe Bay single line electrical drawing ................................................... 45

Figure 21: Existing MCBH Kaneohe Bay electrical map............................................................. 47

Figure 22. Possible future energy costs ........................................................................................ 57

Figure 23. Energy costs in net metering renewable energy scenario............................................ 58

Figure 24. Energy costs in feed in tariff renewable energy scenario............................................ 59

Figure 25. Wind resource on Oahu............................................................................................... 61

Figure 26. Solar resource on Oahu ............................................................................................... 62

Figure 27. Concentrated solar power resource map for Oahu ...................................................... 63

Figure 28. Flood zones.................................................................................................................. 64

Figure 29. Biological sensitive lands............................................................................................ 65

Figure 30. Geothermal resource on Oahu..................................................................................... 66

Figure 31: Biomass resource maps for all Hawaii islands............................................................ 67

Figure 32. Modeled electricity end use office buildings............................................................... 68

Figure 33. Modeled electricity end use in the commissary .......................................................... 70

Figure 34. Modeled electricity end use in barracks...................................................................... 71

Figure 35. Modeled electricity end use in main gym.................................................................... 73

Figure 36. Modeled Electricity End Use Food Services............................................................... 74

Figure 37. Anemometer placement at N.E tip of MCBH Kaneohe Bay....................................... 83

Figure 38. Monthly wind speed profile at MCBH Kaneohe Bay ................................................. 84

Figure 39. Diurnal wind speed profile .......................................................................................... 84

Figure 40. Potential sites for wind turbines.................................................................................. 85

Figure 41. Potential wind turbine placement ................................................................................ 86

Figure 42. Potential wind turbine placement ................................................................................ 86

Figure 43. Potential wind turbine placement ................................................................................ 87

Figure 44. Distribution feeder capacities and load ....................................................................... 88
xiii

List of Tables

Table 1. MCBH Kaneohe Bay Energy Baseline............................................................................ vi

Table 2. Energy Efficiency Savings Potential .............................................................................. vii

Table 3. Renewable Energy Technologies: Potential Energy Savings and Payback Period ........ vii

Table 4. MCBH – Kaneohe Bay Energy Baseline.......................................................................... 9

Table 5. Fuel Use Annual Baseline............................................................................................... 12

Table 6. Project Savings Summary............................................................................................... 16

Table 7. Overall Summary from REO.......................................................................................... 23

Table 8. Total Solar Hot Water..................................................................................................... 25

Table 9. Total Daylighting Savings.............................................................................................. 26

Table 10. PV Capital and Maintenance Costs .............................................................................. 28

Table 11. PV Economic Analysis................................................................................................. 28

Table 12. Cost for a 1.5 MW Wind Turbine................................................................................. 31

Table 13. Economics for 27 MW Wind Farm .............................................................................. 31

Table 14. Electrolyzer and Fuel Cell Calculations ...................................................................... 33

Table 15. Wind Turbine/Grid Hybrid System .............................................................................. 36

Table 16. Wind Turbine/Grid Annual Energy Production............................................................ 36

Table 17. Wind Turbine/Grid Annual Grid Sales......................................................................... 36

Table 18. Wind Turbine Technology and Estimated Number of Turbines for NZEI................... 37

Table 19. PV Modeled Cost.......................................................................................................... 38

Table 20. Wind Turbine/PV/Grid Hybrid System........................................................................ 38

Table 21. Wind Turbine/PV/Grid Annual Production.................................................................. 38

Table 22. Wind Turbine/PV/Grid Annual Grid Sales.................................................................. 38

Table 23. Fuel Use Baseline, MCBH Kaneohe Bay..................................................................... 40

Table 24. Gasoline Savings for Changing to E85......................................................................... 42

Table 25. Gasoline Reduction for Changing to H2....................................................................... 42

Table 26. Energy Efficiency Savings Potential ............................................................................ 49

Table 27. Renewable Energy Technologies: Potential Energy Savings and Payback Period ...... 50

Table 28. Modified Accelerated Depreciation Schedule .............................................................. 53

Table 29. Base Case Energy Costs ............................................................................................... 56

Table 30. Carport PV Sites for MCBH Kaneohe Bay .................................................................. 77

Table 31. Rooftop PV sites for MCBH Kaneohe Bay.................................................................. 78

Table 32. MCBH Kaneohe Bay PV Projects Phased Award Plan................................................ 82
1

1 Introduction

The U.S. Department of Defense (DOD) has long recognized the strategic importance of energy 

to its mission, and is working to reduce energy consumption, as well as to enhance energy 

security by drawing on local clean energy sources. A recent Defense Science Board report stated 

that critical military missions are at a high risk of failure in the event of an electric grid failure.2

Failures may occur as a result of malicious activities (for example, physical or cyber attacks) or 

due to blackouts on an aging electric grid infrastructure. The development of on-site renewable 

energy supplies can reduce this risk, and may become an increasingly important strategic 

concern. Renewable energy can also contribute to improved security of the energy supply and of 

the site. It can decrease energy costs or make them more predictable, as well as increase the 

base’s responsiveness to energy-related Federal or DOD mandates.

In 2008 the DOD and U.S. Department of Energy (DOE) defined a joint initiative to address 

military energy use by identifying specific actions to reduce energy demand and increase use of 

renewable energy on DOD military installations. In light of DOD priorities, early attention was 

given to the possibility of net zero energy installations (NZEI), that is, installations that would 

meet their energy needs with local renewable resources. Because of MCBH Kaneohe Bay’s 

strong history of energy advocacy and extensive track record of successful energy projects, the 

DOE’s National Renewable Energy Laboratory (NREL) selected MCBH Kaneohe Bay to 

receive technical support through the Hawaii Clean Energy Initiative (HCEI) for net zero energy 

assessment and planning.

NREL’s task was to perform a comprehensive assessment of MCBH Kaneohe Bay’s potential to 

achieve net zero energy status and provide energy project recommendations, and assist in the 

development of an optimal energy strategy for the base.

1.1 Overview of the DOD Energy Context

The DOD is the largest energy consumer in the U.S. government. Present energy use patterns 

impact DOD global operations by constraining freedom of action and self-sufficiency, 

demanding enormous economic resources, and putting many lives at risk in associated logistics 

support operations in deployed environments. There appear to be many opportunities to more 

effectively meet DOD energy requirements through a combination of human actions, energy 

efficiency technologies, and renewable energy resources. DOD’s corporate hierarchy offers 

advantages in the implementation of these opportunities at speed and scale: the military has often 

been a market leader in the adoption of new technologies and complex systems. The present 

focus of DOD leaders on exploring improvements to energy provision and use in the departments 

operations—at home and abroad—is timely. 

In fiscal year (FY) 2008, the DOD consumed 889 trillion site-delivered British thermal units 

(Btu) and spent on the order of $20 billion on energy. The majority of DOD energy consumption

is fossil fuel based (coal, oil, natural gas, or electricity produced from these), often from foreign

sources. The DOD accounts for about 1.8% of total U.S. petroleum consumption and 0.4% of the 

world’s consumption. A summary of DOD energy use is shown in Figure 2 below. The focus of 

 2 More Fight Less Fuel, Defense Science Board Report. February, 2008.

www.acq.osd.mil/dsb/reports/ADA477619.pdf. Accessed May 2010.
2

this report is the 26% of energy used in goal subject buildings3

, buildings exempted from these 

mandates, and fleet vehicles. Tactical fuel use is not considered at this time.4

Figure 2. DOD Energy Use Breakdown

1.2 Energy Strategies for DOD Installations: Key Considerations

A net zero energy assessment is a framework for a military installation to develop a holistic and 

systematic energy strategy. An installation’s energy strategy should reflect a number of 

constraints and considerations:

• Mission compatibility: Mission accomplishment is the top priority. Even if attractive by 

other measures, incompatibility with the installation’s mission eliminates any energyrelated proposal. Wind turbines sited near a runway are one example of an energy 

technology incompatible with the flying mission at many military installations. 

• Security: Energy security, surety and reliability, as well as overall physical security of 

the site, must be maintained or enhanced by the installation’s energy system. For 

example, a biomass-fueled power system may not be suitable to some sites due to offsite 

truck traffic required to bring in fuel. On the other hand, the ability to meet an 

installation’s critical load using onsite renewable sources (e.g., landfill gas, geothermal 

power, solar energy) in an islanding mode may greatly enhance energy security. This is 

underscored not only by the threat of malicious activities (e.g., physical or cyber attacks), 

but also by possibility of major blackouts such as have occurred in the U.S. many times 

 3 Federal Buildings are subject to mandated energy efficiency reductions under the National Energy Conservation 

Policy Act (NECPA) and Executive Order 13423. Some buildings are exempt from these requirements. Guidelines 

for exempting buildings can be found here. (http://www1.eere.energy.gov/femp/pdfs/exclusion_criteria.pdf) 4 Alternative fuels are in development and testing. Also, tactical fuel use can be reduced through reduction in tactical 

system use (for example, in favor of simulator-based training), and through application of energy-saving 

technologies (e.g., skin coatings for aircraft and ships, improvements in aerodynamic/hydrodynamic design, hybrid 

drive systems for ground vehicles).
3

in recent decades. More blackouts are anticipated due to aging electric grid infrastructure, 

decreased maintenance investment, increasing loads, and the lack of situational 

awareness on the part of grid operators.

5 A recent Defense Science Board report stated 

that critical military missions are at a high risk of failure in the event of an electric grid 

failure.

6 The development of onsite energy supplies and smart microgrids, which are part 

of a net zero energy solution, can reduce this risk, and may become an increasingly 

important strategic concern.

• Economics: Life-cycle, system-based economic assessment of alternatives should reflect 

such factors as technological maturity; fuel availability and cost; energy storage 

requirements; distribution and interconnection arrangements; financing options; 

federal/state/local incentives; environmental impacts; and costs for 

operations/maintenance and repair/replacement.

• Agency goals and federal mandates: The DOD has a strategic energy plan to reduce 

consumption, leverage new technologies, drive personnel awareness, and increase energy 

supply; a primary goal is to achieve 25% renewable electrical energy use by 2025. 

Further, the Army has a plan to create five NZEIs by 2025. By creating these installations 

the Army will help meet is additional energy security and renewable energy goals. 

• Site resources: Energy system siting opportunities (buildings; disturbed or undisturbed 

land; accessibility) vary among installations, as do local climates, renewable energy 

resources, and electrical system interconnection opportunities.

The contribution of a net zero energy assessment to the development of site-specific energy 

strategies responsive to these constraints is discussed below.

1.3 NZEI Concept

Net zero energy is a concept of energy self-sufficiency based on minimized demand and use of 

local renewable energy resources. While net zero energy status per se is not inherently a high 

priority for DOD installations, it can serve as a design point well suited to a disciplined 

exploration of how energy is provided and used. First developed in the context of individual 

houses, where the challenge is to provide all required energy using onsite renewable resources, 

the concept has been extended in recent years to communities, campuses, and installations. In 

principle, a net zero energy installation, or NZEI, should reduce its load through conservation 

(use what is needed) and energy efficiency (get the biggest bang from the energy buck), then 

meet the remaining load through onsite renewable energy. Defining an NZEI is complicated by 

the need to consider – in addition to individual buildings, public facilities and infrastructure – the

questions of how to treat energy used for various forms of transportation, and mission – specific

energy requirements such as tactical fuel demands. 

The NZEI concept is shown graphically in the figure below. 

 5 The Smart Grid, An Introduction. US Department of Energy. No.DE-AC26-04NT41817, Subtask 560.01.04, 

http://www.oe.energy.gov/DocumentsandMedia/DOE_SG_Book_Single_Pages.pdf. Accessed April 2010. 6 More Fight Less Fuel, Defense Science Board Report. Febuary, 2008.

http://www.acq.osd.mil/dsb/reports/ADA477619.pdf Accessed May 2010.
4

Figure 3. Net Zero Energy Concept

The original definition of an NZEI adopted by the DOD-DOE task force was, “An installation 

that produces as much energy on or near the installation, as it consumes in its buildings and 

facilities.” The definition was elaborated in consultation with the task force to include a focus on 

renewable energy, on-site generation, and fleet fuel use. The following definition was used for 

this assessment: 

“A net zero energy military installation produces as much energy onsite from 

renewable energy generation or through the onsite use of renewable fuels, as it 

consumes in its buildings, facilities, and fleet vehicles.”

A more detailed explanation of this elaboration and the net zero definition is given below. 

• “Net Zero” means that the energy produced onsite over the period of a given year is equal 

to the installation’s energy demand. This implies a connection to a local power grid, 

which in a sense “banks” the energy. Thus onsite renewable resources, say, solar energy 

systems, may produce energy greater than that used by the installation during the day, 

with excess energy fed into the local grid. At night, when the solar system is not 

producing energy, the installation relies on energy from the grid. 

• Energy consumption may be in the form of electricity, heat, or direct use of fuel. 

• A military installation is taken to be any defined facility, which may be a contiguous area 

or may comprise separate areas. When assessing the energy of the installation, all 

activities within the defined boundaries are included regardless of whether their energy is 

managed by the base energy manager, or paid for by different agencies. 

• The task force’s willingness to include energy production “on or near the installation” 

was left open to interpretation. The assessment team focused primarily on the 

possibilities of onsite energy production, accepting forms of energy generated onsite from 

renewable sources and renewable fuel used onsite. The set of onsite renewable energy 

sources followed standard DOE practice: commercially available solar (photovoltaic, 

Typical 

Community

Option 0

Energy Efficiency 

and Energy 

Demand Reduction

Energy Load ($ or btu or CO2)

buildings

vehicles

industry

Maximize 

efficiency, 

minimize 

demand

Renewable 

Option 1

Renewable 

Option 2

Renewable 

Option 3

Some combination 

of options 1, 2 & 3 

meet remaining load
5

concentrating solar power, water heating), wind and hydropower systems, and electricity 

or heat generated from natural gas produced in onsite landfills or by burning the 

installation’s trash or municipal solid waste (waste-to-energy). 

o Renewable fuels include various forms of biomass (wood waste, agricultural 

byproducts); methane produced, for example, from external landfills or as a 

byproduct of sewage processing; and various renewable transportation fuels 

(ethanol- E85, biodiesel).

o As employed here, the net zero energy concept does not include non-primary 

energy imported from offsite (e.g., electricity from a local offsite renewable 

source), or purchases of renewable energy credits (RECs), that is, getting credit 

for renewable energy generation somewhere else in the world. This is in keeping 

with the NZEI concepts’ emphasis on meeting energy needs with local resources.

• The task force definition does not explicitly discuss minimizing the installation’s load, an 

essential first step toward net zero energy status. This can be accomplished through 

personnel actions to conserve energy or reduce energy waste, or by identifying 

approaches to conserving energy without impacting the mission. This also includes the 

implementation of standard facility energy efficiency technologies to the extent that is 

economically feasible. These may include heating, ventilation and air conditioning 

(HVAC) and lighting upgrades (efficient chillers and boilers, solar ventilation pre-heat, 

fluorescent or light-emitting diode (LED) lighting); environmental control systems; 

systems generating both electricity and heat (cogeneration systems) where both forms of 

energy are needed; and building envelope upgrades or design features such as insulation, 

high-performance windows, and daylighting.

• Installation energy consumption can be measured several ways. Possible measurement 

approaches include:

o Net Zero Site Energy: Energy used by the installation is accounted for at the site, 

for example, as indicated by building electricity and gas meters. This approach is 

generally straightforward, but omits transmission losses to bring energy to the 

site.

o Net Zero Source Energy: Source energy refers to the primary energy used to 

generate and deliver the energy to the site, for example: a local utility generation 

site and transmission system. For transportation fuel, source energy would include 

a multiplier to account for the energy required to transport the fuel to the fueling 

station. 

o Net Zero Energy Costs: In this approach, the amount of money the utility pays 

the installation for renewable energy generated onsite and exported to the grid is 

compared with the amount the owner pays the utility for energy used over a year. 

o Net Zero Energy Emissions: Here the installation aims to produce onsite and use 

at least as much clean renewable energy as it uses from offsite local energy 

sources annually, offsetting the offsite emissions. (Torcellini et al7

)

 7 Torcellini et al. (2006), “Zero Energy Buildings (ZEB): A Critical Look at the Definition.” Golden, Colorado: 

National Renewable Energy Laboratory.
6

Net zero source energy was selected as the basis for energy accounting for this assessment 

because it is the most representative measure of primary energy consumption.

• Transportation fuel use is included with the following limitations: All transportation fuel 

consumption data is gathered for the purpose of establishing an installation’s total 

footprint, data permitting. This can include government ground fleet vehicle fuel use, fuel 

associated with commercial air travel for official business, fuel used in personnel 

commuting, and tactical fuel use. However, only the government fleet use is further 

addressed in the NZEI; potential reduction measures include converting to electric 

vehicles, using electricity generated onsite from renewable sources, or the use of 

renewable fuels in fleet vehicles. 

Since the DOD’s capability to significantly affect energy used in commercial air travel 

and by commuters is limited to minimizing trips, encouraging carpooling or 

telecommuting (where possible), or providing electric vehicle charging stations as an 

incentive for employees to consider electric vehicles when these become widely 

commercially available, these categories are not considered. Tactical fuel requirements 

are not addressed in the assessment since renewable fuel alternatives are not yet 

commercially available. DOD can (and does) examine training requirements and 

opportunities to use simulators instead of real tanks/personnel carriers, aircraft, ships and 

submarines, and also to explore logistical variations in theater that can also reduce fuel 

use, but these options are not addressed here.

Again, the NZEI concept can be seen as a useful entry point into an exploration of demand 

reduction through human action and energy efficiency technology, and meeting remaining 

energy needs with local renewable energy resources. Some installations will be able to exceed

net zero status to become net energy producers, while others won’t be able to approach it. In fact, 

a net zero goal too strictly applied can lead to solutions that make poor sense from economic or 

other perspectives. Assessment of a site’s net zero potential, combined with consideration of the 

other constraints identified in the preceding section, provides a disciplined basis for identifying 

an optimal energy strategy tailored to the requirements of each site.

1.4 Assessment Approach

The approach developed for this assessment includes seven steps, which are briefly summarized 

here and addressed in detail in the remaining chapters of this report.

• Establish MCBH Kaneohe Bay Energy Baseline (Section 2): Identify the installation 

mission, geographic boundaries, and any special energy requirements (e.g., reliability, 

performance in emergency situations, etc.). Summarize annual (source) energy used by 

all identified sources supporting the mission as well as its type and means of distribution. 

Become familiar with energy projects already planned onsite.

• Demand Reduction through Human Action (Section 3): Identify approaches to 

minimizing wasted energy while maintaining or improving the quality of mission 

execution.

• Energy Efficiency Project Assessment and Recommendations (Section 4): Identify 

specific onsite energy-efficiency projects and their effect on installation energy demand.
7

• Renewable Energy and Additional Load Reduction Projects (Section 5): Identify 

projects exploiting onsite renewable energy for electricity and heat production, or 

employing renewable fuels onsite for electricity production or for fleet transport. 

• Transportation Assessment (Section 6): Identify projects to reduce and replace fossil 

fuel use in fleet vehicles.

• Electrical Assessment (Section 7): Outline the characteristics of a smart microgrid to 

support emergency operations in the event of a public grid outage. Identify the impacts of 

renewable energy projects on the microgrid.

• Characterize MCBH Kaneohe Bay Net Zero Energy Potential (Section 8): Bringing 

together findings from the preceding chapters, calculate the extent to which the 

installation can approach net zero energy status. Then, with reference to broader 

installation and mission constraints, recommend a set of energy projects.

• Outline Implementation Steps (Project Planning and Financial Assessment) (Section 

9): Demonstrate how the recommended projects, in concert with projects already planned 

by the installation, can be implemented - with attention to timelines and financing 

alternatives.
8

2 MCBH Kaneohe Bay Energy Baseline

2.1 Overview

The first step in a net zero energy assessment is to determine an energy baseline. The baseline is 

used to evaluate net zero energy potential and includes energy use in on-site buildings, facilities,

and fleet vehicles. The baseline serves as a reference point against which to measure progress.

2.2 Site Description

Marine Corps Base Hawaii (MCBH), Kaneohe Bay is located on the eastern side of Oahu, 

Hawaii. The MCBH is on the Mokapu Peninsula between Kane’ohe Bay and Kailua Bay. MCBH 

Kaneohe Bay is separated from the Honolulu area by the Ko’olau Mountain Range. This coastal 

region is referred to as “windward” Oahu since it is exposed to northeasterly trade winds.

2.3 MCBH Kaneohe Bay Boundary

This study will be concentrating on the MCBH Kaneohe Bay only and does not include Camp 

H.M. Smith, Marine Corp Training Area Bellows, Manana Housing area, or Puuloa Training 

Facility that are often associated with this installation. Figure 4 and Figure 5 are maps from the 

MCBH Master Plan 2006 and show the boundary area of MCBH Kaneohe Bay addressed in this 

study.

Figure 4. MCBH Properties 

Source: MCBH Master Plan 2006
9

Figure 5. Land use zones 

Source: MCBH Master Plan 2006

2.4 Total Consumption Breakdown

Working with MCBH Kaneohe Bay, NREL determined an energy boundary for the MCBH 

Kaneohe Bay baseline that includes all on-site buildings and facilities, and fleet vehicles. An 

energy baseline provides an analysis of current energy consumption on base, as well as a metric 

against which to measure progress. Baseline energy consumption for MCBH Kaneohe Bay is 

shown below.

Table 4. MCBH – Kaneohe Bay Energy Baseline

Baseline Annual Energy Usage Information 2009

Energy Use units Site

MMBtu

Source

MMBtu

Electricity 107,088,800 kWh 365,387 1,432,317

Propane 18,890 MMBtu 18,890 21,724

Gasoline 181,802 Gallons 20,744 23,855

Diesel 93,967 Gallons 13,860 15,939

Total Energy Use 418,881 1,493,835

The total site Btu’s are 418,881 Million British thermal units (MMBtu). These site Btu values 

were converted into source Btu utilizing conversion factors developed by NREL (3.92 source 

Btu/site Btu for electricity and 1.15 source Btu/site Btu fuel). The total source Btu is 1,493,835

MMBtu. 95.88% of the source Btu’s are from electricity and 4.12% are from fuels. 
10

Many people are familiar with site Btu or site energy, which is the amount of fuel and electricity 

consumed and reflected in utility bills. However, energy may be delivered to a facility as either 

primary or secondary energy. Primary energy is raw fuel that is burned onsite to create heat or 

electricity. Secondary energy is the product of the combustion of the raw fuel as thermal energy 

or electricity. It is not possible to directly compare primary and secondary energy because the 

former is a raw fuel and the latter is a product of combustion of the raw fuel. Utilizing source 

energy as the common metric for analysis, as is done for this assessment, permits comparison of 

the two energy types, and also better supports assessment of DOD goals for fossil fuel reduction 

and renewable energy generation. A source Btu analysis allows for the accounting of the energy 

required to transport fuel to the base and the energy losses due to inefficiencies in the electrical 

generation process. For raw fuels, the difference between site and source energy is minimal and 

accounts for fuel distribution and dispensing but not fuel production. For example, diesel fuel 

losses for fuel transport, storage, and dispensing are accounted for, but energy used in extracting 

crude oil and refining it into diesel fuel is not accounted for. The same basic analysis applies for 

electricity: losses in producing the fuel to be combusted for electrical energy production are not 

accounted for. However, the losses in the conversion of a primary chemical fuel, such as coal, to 

a secondary fuel, such as electricity, are accounted for.

The calculation of a conversion factor to translate between site and source Btu for a specific 

installation can be difficult. The exact ratio will depend on many factors such as the location of 

the installation, the efficiency of the energy distribution system, and the location from which the 

installation’s energy is sourced. For example, the electrical energy conversion factor will depend 

on the specific power plant from which an installation receives its energy, its efficiency, and the 

proximity to the installation. Analyzing a site-to-source conversion in this manner will penalize 

or credit an installation based on the relative performance of its electrical energy source. 

However, it would be unfair and impractical to trace installation energy use down to the level of 

a specific power plant. Additionally, location is a factor outside the control of an installation. 

For this analysis a Hawaii specific electrical site-to-source ratio and national ratios for propane

were utilized. 

2.5 The Electrical Baseline

Grid Connection

We obtained MCBH Kaneohe Bay’s load profile from 15-minute metered data from the 

Hawaiian Electric Company (HECO) website databases for 2009. We also received monthly 

utility consumption. Figure 6 shows the typical day load and Figure 7 depicts the annual load 

profile. The daily-load profile shows electricity use peaks around noon and tapers off around 

7:00 pm. The annual load profile shows an annual peak load of 18 megawatts (MW) that 

occurred in August and October.
11

Figure 6: Typical daily load profile 

Figure 7: Annual load profile
12

2.6 Propane Baseline

Propane use at MCBH Kaneohe Bay was provided to NREL for FY09. This data was utilized to 

establish the annual propane baseline of 206,900 gallons which is equivalent to 18,890 MMBTU. 

Propane is used for hot water at MCBH Kaneohe Bay. This includes barracks boiler plants, 

officers club, laundry, gym, and clinics. 

2.7 Transportation Baseline

NREL personnel visited MCBH Kaneohe Bay in early 2010 and in March 2011, and were able to 

obtain basic information about their total fuel consumption at MCBH Kaneohe Bay. MCBH 

Kaneohe Bay provided tactical jet fuel (JP-8), gasoline, and diesel fuel use data for 2009. The 

breakdown of fuel use by gallon is shown below.

Table 5. Fuel Use Annual Baseline

Baseline Annual Fuel Usage Information

Total Gasoline (gallons) 181,802

Total Diesel (gallons) 93,967

Total JP-8 (gallons) 9,335,777 

JP-8 is exclusively used for tactical use and is the majority of the fuel consumed, thus tactical use 

accounts for the bulk of the transportation related baseline as shown in Figure 8.

The amounts of fuel used for tactical operations are outside of the control of the installation 

energy managers. Although there are opportunities for future analysis in examining the potential 

to reduce the use of fuel in training operations, this project did not include this use. 

Figure 8. Fuel use at MCBH Kaneohe Bay 2009

MCBH Kaneohe Bay is well on their way to transforming the way their fleet is fueled. In 2011,

both E85 and B20 fueling stations were installed. Existing flex-fuel vehicles are fueled with E85 

and the large diesel vehicles are fueled with B20. MCBH Kaneohe Bay is transferring to electric 

1.89% 0.98%

97.13%

Gasoline

Diesel

JP-8
13

and hydrogen fleet by 2020. Hydrogen will be generated on base with electrolysis equipment that 

is being installed this year. 

2.8 Utility Costs

The current cost of energy is one important factor in determining the economic viability of 

investments in energy efficiency or renewable energy. MCBH Kaneohe Bay’s electrical energy 

is provided by the Hawaii Electric Company (HECO) to the main base substation. The base 

owns, operates, and maintains the distribution network beyond the substation. 

The cost of electricity averaged for the whole year at MCBH is summarized below:

• 2007: $0.17/kilowatt-hour (kWh) (unit cost + demand)

• 2008: $0.26/kWh (unit cost + demand)

• 2009: $ 0.16/kWh (unit cost + demand)

Energy at MCBH Kaneohe Bay has been quite volatile over the last several years. The volatility 

in the rate is largely due to the fact that the majority of energy production on the island is from 

diesel fuel, which is derived from crude oil. The cost of electricity tracks and follows the cost of 

oil, which is a volatile commodity. The price of oil versus the cost per kWh for Hawaii over the 

last few years is shown in the figure below. 

Figure 9. Hawaii Electric Cost versus the Price of Oil7

The range in electrical costs each month for 2009 was from $0.164-0.23/kWh. NREL spoke with 

MCBH Kaneohe Bay and agreed to use $0.20/kWh in this analysis.

The total cost for propane at MCBH Kaneohe Bay in FY09 was about $427,272. The cost per 

gallon of propane was approximately $2.00. 

 7 Hawaii Energy. http://www.hawaiienergy.com/10/hawaii-residential-electric-cost-and-oil-cost-per-kwh Accessed 

September, 2010. 
14

3 Reducing Energy Demand by Engaging People

Having established baseline energy use, analysts turned to the task of identifying the most 

economic ways to reduce the installation’s energy demand. There are two main approaches: 1)

identifying actions to reduce energy use without the need for capital expenditures, and 2) 

implementing energy-efficient technologies and design strategies. Identifying opportunities for 

procedural, behavioral, process, or operational energy-saving actions relies on engaging the 

attention and creativity of personnel, especially those with experience at the installation.

Implementing energy-efficient technologies and design strategies is largely a technical exercise, 

which the next section will address.

Security, economic, and environmental objectives support a DOD-wide—and national—

transition to clean energy that may be viewed, in part, as a culture change, requiring individual 

awareness of energy costs, new habits of energy use, and continuing creative attention to ways of 

reducing energy demand. There is no silver bullet or purely technological solution to our present 

energy challenges: even with the adoption of energy efficient technologies, there is a tendency 

for energy demand to increase with growing populations and the arrival of new generations of 

energy-using devices. In conjunction with an NZEI analysis, DOD leaders should institutionalize 

ways of engaging peoples’ ingenuity to reduce energy demand. It should be emphasized by the 

superiors/management that wasting energy goes against the values and goals of the DOD’s 

mission and therefore all personnel should be required to conserve. This assessment does not 

attempt to quantify energy reductions due to behavior changes; however, the outline of a 

recommended approach follows.

• Assess potential demand reduction: Estimate potential energy demand reductions 

from personnel actions, changes to processes, improvements to mission execution,

and other sources (provide estimates in energy units and dollars). Create dedicated 

teams in functional areas across the installation’s operations to identify actions to 

permanently minimize energy use. Suggested actions should have a neutral effect on 

mission performance, or improve it. Consider energy use in facilities (lighting 

intensity, heating or air conditioning set points, and hours of operation), transport 

(vehicle miles, need for travel versus teleconferencing or videoconferencing), and 

mission uses (required hours of use of aircraft/ships/subs/ground vehicles for training 

and operations). 

• Continuous improvement: Beyond the net zero energy assessment, MCBH Kaneohe 

Bay can engage peoples’ ingenuity in saving energy on a continuing basis: 

o Institute an “Energy Awareness” campaign: Establish attention to energy 

use as a normal part of all activity, including planning, training, and mission 

execution.

o Create competitions/contests/incentives for new ideas, or for reduced 

energy use: Make it a point of pride to help increase national energy 

independence through reducing dependence on energy from imported and/or 

“dirty” sources. 
15

o Create leadership/personnel teams to continue developing ways to save 

energy: Leading by example is a powerful influence across officer, enlisted, 

government civilian, and contractor elements of the military team.

o Implement energy scoreboards: The scoreboards would assess energy usage 

by individuals, buildings, or organizations and recognize best performers and 

practices.

The Federal Energy Management Program has published several guides on how to conduct an 

energy awareness campaign: 

Creating an Energy Awareness Program

http://www1.eere.energy.gov/femp/pdfs/yhtp_ceap_hndbk.pdf

Handbook from the Federal Energy Management Program on how to create an energy 

awareness program and campaign. 

Promoting Behavior Based Energy Efficiency in Military Housing

http://www1.eere.energy.gov/femp/pdfs/military_hndbk.pdf

Handbook from the Federal Energy Management Program on promoting energy efficiency in 

military housing.

Energy Managers Handbook

http://www.wbdg.org/ccb/DOD/DOD4/DODemhb.pdf

Department of Defense Handbook for energy managers that provides tools to help facility and 

installation energy managers perform their jobs more effectively by answering questions and 

illustrating best practices.
16

4 Energy Efficiency Assessment 

4.1 Overview

Energy efficiency is typically the most cost effective energy project investment. Prior to 

conducting further analysis of the renewable energy generation technologies, the potential for 

energy efficiency improvement potential should be evaluated. Energy efficiency and 

conservation analysis were conducted first as they will reduce the electrical and propane fuel

loads at the base and decrease the sizes of the renewable energy systems required. 

MCBH Kaneohe Bay has several projects already planned to increase the efficiency of its 

building portfolio. The NREL team was not able to include all of these measures in the analysis 

of efficiency improvement potential for the base. The savings outlined in this report reflect the 

energy efficiency measures that were identified at the time of the site visit. 

The energy efficiency measures proposed below were done on a high level with very general 

base information. These calculations should not be considered investment grade calculations, and 

should not be used for determining the economics of a potential investment. The 

recommendations should only be used for planning, and for the purpose of identifying energy 

conservation measures (ECMs) for further investigation.

4.2 Summary of Proposed Energy Efficiency Projects

It was beyond the scope of this project to conduct detailed energy audits of the approximately 

163 installation facilities at MCBH Kaneohe Bay. However, through discussion with base 

personnel, and a walk-through of several of the facilities on base the savings potential for energy 

efficiency at MCBH Kaneohe Bay was estimated by auditing a few representative buildings. 

• Total electrical reduction = 18,233 megawatt-hours (MWh) or 62,221 MMBtu (17.03% 

electrical load reduction)

• Total propane reduction = 1,251 MMBtu (6.62% propane load reduction)

• Total reduction = 63,462 MMBtu (16.5% total reduction)

The savings estimates are shown in Table 6 below:

Table 6. Project Savings Summary

Measure Savings (% of fuel type) MMBtu 

Equivalent 

Savings

% Total Site 

Savings

Specific Base Facilities

Commissary (32% reduction) MWh 1,401 2.4% 4,780 2.1%

Barracks (40% reduction) MWh 7,497 12.8% 25,587 11.4%

Offices (43% reduction) MWh 3,215 5.5% 10,972 4.9%

Gym (52% reduction) MWh 467 0.8% 1,593 0.7%

Mess Hall (40% reduction) MWh 1,310 2.2% 4,470 2.0%

Base Wide ECMs

Retro-commissioning MWh 2,023 3.5% 6,904 3.1%

Lighting Occupancy Sensors MWh 935 1.6% 3,190 1.4%

Computer Energy Mgmt MWh 1,387 2.4% 4,732 2.1%

Water Heater Boilers MMBtu 1,251 4.8% 1,251 0.6%
17

Measure Savings (% of fuel type) MMBtu 

Equivalent 

Savings

% Total Site 

Savings

Total

Electricity MWh 18,233 17.03% 62,211 15.9%

Propane MMBtu 1,251 6.62% 1,251 0.6%

Total 

MMBtu

63,462 16.5%

4.3 Base Wide Conservation Measures

Numerous recommendations were developed to reduce energy usage across all base facilities. 

Central Energy Plants

The majority of the cooling systems on the base were distributed single building systems. There 

were only a couple of places on the base where there were central energy plants. The exchange 

and the food courts were on a large water cooled chiller that was recently brought on line. 

According to the onsite staff, the plant was designed with the intention of expanding the capacity 

to the commissary and a few other surrounding buildings. The site is encouraged to pursue this 

opportunity, and expand the central cooling plant. The commissary currently cools water using 

relatively old air cooled chillers, and could greatly reduce the amount of energy required to cool 

the facility by switching over to the central plant. The commissary is currently the largest energy 

user on the base, and has a large potential for improvement. 

The other locations that utilize central cooling plants are the barracks. It was observed during the 

site visit that several of the barracks buildings share air cooled chillers. These central chillers 

should be replaced with water cooled chillers. The replacement chillers should specify a 

coefficient of performance (COP) of six or higher. 

Further on-site studies would be necessary to confirm current operation and feasibility of 

implementation.

HVAC - Chillers

Many of the facilities at MCBH Kaneohe Bay are operating moderately efficient chillers. There 

is a mix of water cooled, and air cooled chillers on the base. Water cooled chillers are much 

more efficient than air cooled chillers, and the high price of electricity at MCBH Kaneohe Bay

would allow a very quick return on investment for high efficiency chillers. It is recommended 

that all chillers over 75 tons be replaced with water cooled chillers. Because of the corrosive 

environment at MCBH Kaneohe Bay, air cooled chillers are typically replaced every 5 years. 

Most water cooled chillers are located indoors as opposed to the air cooled chillers which are 

often kept outdoors. This reduced exposure to the caustic environment would extend the life of 

the equipment. The cooling tower of the water cooled chiller would still be exposed to the 

elements, but cooling towers are much less expensive to replace than chillers. It is recommended 

that all facilities be analyzed for high efficiency chiller upgrades as it is likely significant savings 

potential exists across the base. 
18

HVAC - Air Handling Units

There is a mix of constant volume (CV) and variable air volume (VAV) air delivery systems at 

MCBH Kaneohe Bay. According to the onsite staff, all new construction uses VAV systems, but 

all of the old construction has CV systems. Upgrading the remaining units to VAV systems 

would save energy by reducing the amount of air that would need to be cooled. It is 

recommended that the AHU across the base be evaluated and upgraded to VAV models where 

appropriate. 

Water Heating 

The efficiency of the domestic hot water boilers at MCBH Kaneohe Bay varies; some of the 

boilers are old and inefficient while others are new. A substantial amount of energy could be 

saved by replacing all of the old inefficient boilers with new high efficiency boilers. It was 

observed that there were several chillers equipped with heat recovery units. This type of system 

can save large amounts of energy, so these should be implemented wherever possible to offset 

hot water loads on the boilers. Boilers with efficiencies less than 85% should be examined for 

replacement potential with high efficiency boilers that can reach up to 95% efficiency. Factors to 

be considered include expected time to replacement of existing as well as required supply and 

return water temperatures. Note that 95% efficiency is available with condensing boilers, but 

they require low return water temperatures that are not applicable for all applications. The 

estimated energy savings for high efficiency boilers is 1,251 MMBtu.

Energy Star Refrigerators

Energy savings could be realized by replacing refrigerators on the main base with energy star 

models. It is assumed that small refrigerators are located in each of the barracks units and it was 

assumed that the office buildings contained them as well. Savings would vary by the model 

being replaced but would be 50-200 kWh per year for each fridge. 

Controls

According to the onsite staff, 70 of the 163 buildings on the base have direct digital controls 

(DDC) and are connected to the central control system. It is unknown whether the remaining 

buildings are scheduled to be added to the DDC system or not. All of the buildings that have 

HVAC systems should be added to the central DDC system. This will allow the implementation 

of base wide set points, night time setbacks, and will allow optimization of the system operation 

that would not otherwise be possible. A central DDC system could potentially save a significant 

amount of energy. The base requires numerous control system upgrades (i.e. replace pneumatic 

system) and building retro commissioning. Some of the potential control upgrades include:

• Chiller optimization (chilled water reset and sequencing)

• Cooling tower optimization (recommendation to only run as many fans as needed to meet 

condenser water set point)

• DDC controls

• Electric demand limiting

• Static pressure set point adjustment

• Mixed air dampers – for economizer
19

• Night setback

• Night purge (night-pre cooling of bldg)

• Occupancy sensor control

• Lighting scheduling (centralized lighting control)

• Optimal start/stop HVAC systems

• Outdoor air reduction

• Supply air reset

• VAV and variable pumping.

Retro commissioning of all mechanical systems

The entire base should be retro commissioned building by building. Retro commissioning 

involves going through all of the mechanical systems of a building, verifying operation, and 

optimizing all functions. Retro commissioning can resolve operating problems, improve 

occupant comfort, and reduce energy use. During retro commissioning, the systems are not 

replaced with more efficient components; instead, the existing systems are given a tune-up. The 

American Council for an Energy Efficient Economy estimated that retro commissioning could 

save 5-20% of building energy consumption.8 The estimated energy savings for retro 

commissioning is 2,023 MWh per year.

Plug Loads

The NREL team utilized its screening tools to estimate the potential for plug load reduction at 

MCBH Kaneohe Bay. Currently, there is no computer power management program in place. One 

of the largest energy users in an office setting is computers. By implementing a computer 

program management program, the computers can be put in an energy saving mode when not in 

use. This can save a significant amount of energy. Savings were estimated for utilizing power 

management software on 3,000 desktop computers. The estimated energy savings for plug load 

reduction is 1,387 MWh per year.

Occupancy Sensors 

There are few working occupancy sensors currently installed in the office buildings at 

MCBH Kaneohe Bay. Occupancy sensors can save energy by turning off lights when 

spaces are unoccupied. Large cubicle workstation areas, conference rooms, private offices, 

and restrooms comprise the majority of the lighting load in a typical office building. It is 

likely that many of these areas are intermittently occupied or vacant throughout the course 

of the day, and energy savings could be realized by installing occupancy sensors.

 8 “Retrocommissioning Program Strategies to Capture Energy Savings in Existing Buildings”. Jennifer Thorne and 

Steven Nadel. American Council for an Energy Efficient Economy. June 2003. 

http://www.aceee.org/pubs/a035full.pdf
20

Figure 10. Typical ‘small office’ wall switch sensor application and coverage

 

Figure 11. Typical 'open space' ceiling mounted sensor application and coverage

It is recommended that MCBH Kaneohe Bay install ceiling-mounted, infrared occupancy sensors 

to automatically activate and deactivate space lighting circuits based on occupancy. This 

measure will not reduce peak demand but will reduce annual energy consumption. The estimated 

energy savings for infrared occupancy sensors is 935 MWh per year.

The analysis of building specific energy efficiency measures can be found in Appendix B.

4.4 Privatized Housing

At the time of the assessment the NREL team was unable to conduct an analysis of the

residential energy efficiency potential at MCBH Kaneohe Bay. 

However, there are some ECMs that are typical to most residential housing developments. The

following ECMs were not identified at the site, but could potentially be applicable: 

• Install programmable thermostats to save on cooling

• Install low flow faucets, shower heads and toilets

• Decrease ventilation levels

• Use seasonal natural ventilation

• Add insulation to the walls and attic
21

• Replace existing windows with high performance low-e windows

• Use interior shading to reduce cooling loads

• Replace all lighting with florescent technology

• Replace current domestic hot water heaters with high efficiency water heaters

• Switch out any appliances that aren’t currently Energy Star 

• Encourage residents to save energy with energy awareness campaigns and incentives

• Reduce irrigation use 

• Turn off the power and gas to unoccupied homes to eliminate standby losses.
22

5 Additional Load Reduction and Renewable Energy Projects

5.1 Overview

After reducing the energy use through conservation measures, the remaining energy needs of an

NZEI are met through renewable energy. In addition to the basic resource assessment, the NREL 

team conducted an initial assessment of the renewable energy opportunities for MCBH Kaneohe Bay

based on high-level energy data provided by MCBH Kaneohe Bay and the Navy staff, using resource 

potential and NREL’s Renewable Energy Optimization (REO) software tool. The initial screening 

evaluated the following technologies: 

Further load reduction:

• Daylighting

• Solar hot water 

• Geothermal/Ground source heat pump

Renewable energy generation projects:

• PV 

• Wind energy

• Solar thermal or CSP 

• Biomass gasification CoGen/Boiler

• Anaerobic digesters

5.2 Renewable Energy Resource Assessment

NREL began its analysis of the renewable energy generation potential of MCBH Kaneohe Bay

by examining the high-level resource and project potential. The analysis includes MCBH 

Kaneohe Bay’s specific solar and wind resource maps, Appendix A. The renewable energy 

resource maps were provided by the NREL geographic information system (GIS) group. Overall, 

the resource maps indicate good solar and wind resource potential, moderate geothermal 

potential, and poor biomass potential. 

Also included in Appendix A, are maps of biological sensitive land areas and flood zones. The 

environmental maps were obtained from the MCBH Master Plan for MCBH Kaneohe Bay 2006. 

These maps help in determining potential areas for implementing renewable energy projects.

Solar

The solar resource map for PV indicates that all of MCBH Kaneohe Bay falls in the 5.75 – 6.00 

kWh/m2

/day category, which indicates a good resource. The direct-normal solar resource is also 

significant at 5.50 – 6.00 kWh/m2

/day. Direct-normal radiation excludes scattered light that 

results from humidity and atmospheric particles. It is a measure of only the direct, or shadow-
23

casting, sun rays. High direct-normal radiation levels are good for systems that focus or 

concentrate the sun’s rays on central collector or pipe.

Wind

The wind resource is good (class 4-5, see wind resource map in Appendix A), and NREL has

wind-speed data that was monitored over a year-long period (August 1, 2009-July 31, 2010).

More detailed information is available in the “Kaneohe, Hawaii Wind Resource Report.”

Geothermal/Ground Source Heat Pump 

Information on the direct geothermal resource at MCBH Kaneohe Bay was not available. The 

national version of the geothermal resource map indicates moderate geothermal project potential at 

the site. During the site visit to MCBH Kaneohe Bay base personnel stated that the area had 

problems with ground shift and ground source heat pumps would likely not be possible. Since the 

industry is not fully developed and project costs for retrofits are higher than new buildings, NREL 

did not consider this technology.

Biomass

The biomass resource on the island of Oahu, particularly in the vicinity of MCBH Kaneohe Bay, 

is not sufficient to support the development of a large scale biomass energy project. 

Presently MCBH Kaneohe Bay has a 35,800 ft3 anaerobic digester that is not currently in use. 

The anaerobic digester is located at the waste water treatment facility. To achieve the net zero 

energy solution NREL included the existing digester in the analysis. 

5.3 Renewable Energy Optimization

Following our analysis of renewable energy resources, we used NREL’s REO tool to estimate 

the sizes of each technology required to achieve net zero. REO suggested the following 

technology sizes in Table 7 below:

Table 7. Overall Summary from REO

Considered Technology Total 

Capacity

Central 

Plant 

Capacity

Buildinglevel 

Projects

Initial 

Investment

Annual 

Savings

Quantity $ $/year

Photovoltaics kW 8,509 8,509 0 $ 57,201,071 $ 2,358,340 

Wind Energy kW 43,890 43,890 0 $ 104,193,884 $ 898,304 

Solar Ventilation Air Preheat ft2 0 - 0 $ - $ - 

Solar Water Heating ft2 257,509 - 130 $ 31,536,377 $ 97,031 

Solar Thermal Parabolic Trough ft2 0 0 - $ - $ - 

Thermal Storage therms 0 0 - $ - $ - 

Solar Thermal Electric kW 0 0 - $ - $ - 

Biomass Gasification Boiler MBH 0 0 - $ - $ - 

Biomass Gasification Cogen MBH 0 0 - $ - $ - 

Biomass Anaerobic Digester ft3 35,800 35,800 - $ 0 $ 203,365 

Biomass Anaerobic Digester Cogen ft3 116 116 - $ - $ 203,365 

Skylight Area ft2 99,140 - 78 $ 4,320,360 $ 377,745 
24

Considered Technology Total 

Capacity

Central 

Plant 

Capacity

Buildinglevel 

Projects

Initial 

Investment

Annual 

Savings

Ground Source Heat Pump tons 0 - 0 $ - $ - 

Total 444,964 88,315 208 $ 197,430,691 $ 4,138,150 

Several technologies were eliminated from further analysis based on the resource assessment, REO 

screen, and discussions with MCBH Kaneohe Bay. Technologies eliminated from additional analysis

are, Solar thermal CSP, biomass, and geothermal/ground source heat pump. Technologies to be 

considered further are: solar hot water, daylighting, PV, small CSP (dish), wind turbines, fuel cells,

existing anaerobic digester, and existing hydro (wave energy).

5.4 Solar Hot Water

The NREL team evaluated the feasibility of installing solar water heating systems on 28 of the 

buildings at MCBH Kaneohe Bay. The system utilizes an insulated flat-plate collector that 

preheats water before entering the existing water heater, thus reducing the amount of fuel that 

must be used to heat the water. The system would utilize a preheat tank to store the heat, and a 

pump to circulate the water. The proposed system was designed to provide a solar fraction of 

approximately 60%, meaning 60% of the total water heating load is provided by solar energy.

Figure 12 shows a schematic of how the system should be laid out. The tank labeled “aux tank”, 

meaning ‘auxiliary tank’, would be the existing water heater. Water is pumped through this 

system when the controller detects that the solar collector is hotter than the preheat tank. 

Figure 12. Direct SHW system

If the water from the solar preheat tank is not sufficiently heated, the existing water heater 

compensates accordingly. If no solar heat is available, the existing water heater has the capacity 

to meet all the water heating needs of the building as it did prior to installation of a solar system, 

and the controller will not cycle the pump on. When there is solar energy being collected, the 

solar preheat tank will provide water to the existing water heater that is above the temperature of 

the water coming from the water mains. By heating the tank in this way, the fuel or electricity 

consumed by the existing water heater is reduced.
25

The most common area to mount a solar water heating system is on the rooftop of a building. For 

any building that may be replaced or removed in the next 25 years, the site should consider a 

ground mounted system. 

Solar Collector Parameters:

The solar hot water system was modeled as a selective surface flat plate collector system. The 

slope of the panel collector was set at 21° (Latitude), while the azimuth angle of the collector 

was set at 0° (due South).

Savings Estimates:

All of the system calculations were done using the REO tool. The tool calculated system size and 

energy production. The system production along with the economics for the entire base can be 

seen in Table 8 below. 

Table 8. Total Solar Hot Water

Solar Water 

Heating Area 

(ft2

)

Solar Water 

Heating Heat 

Delivery 

(MMBtu/year)

Solar Water 

Heating Initial Cost 

($)

Solar Water Heating 

Energy Savings 

(MMBtu/year)

Solar Water Heating 

Annual Utility Cost 

Savings 

($/year)

Payback Period 

(years)

257,509 9,589 $31,536,377 11,239 $254,713 14

The energy savings reported are based on 2009 utility data. The energy savings have the 

potential to fluctuate depending on facility usage and troop occupancy rates. The SHW analysis 

assumed that other energy efficiency measures analyzed in this report were installed. However 

the water flow reduction technologies and some energy efficiency technologies will likely be 

more cost effective than a SHW system.

5.5 Daylighting

Technology Overview Daylighting

A complete daylighting system consists of apertures (skylights), to admit and distribute solar 

light, and a controller to modulate artificial light in order to achieve energy cost savings. 

Daylighting requires no scheduled maintenance, although skylights may add to roof 

maintenance. Daylighting is screened by using a site’s solar luminance values (from our GIS 

resource database) to determine the optimum amount of skylight area (as a percentage of total 

roof area).We balance savings from reduced electric light usage against the cost of installing a 

daylighting system and the expense of heat loss through the skylights.
26

Figure 13. Daylighting applicable to the MCBH Kaneohe Bay site

Source: FEMP Booklet, NREL/BK-71-25807.

Planned Projects

Skylights have been installed in some of the buildings at MCBH Kaneohe Bay, so a detailed 

assessment of the office building and warehouses would need to be done. NREL’s analysis did 

not include housing, but focused primarily on warehouse and office buildings. 

Economic Analysis

All of the system calculations were done using the REO tool. The tool calculated system size and 

energy production. The system production along with the economics for the entire base can be 

seen in Table 8 below.

Table 9. Total Daylighting Savings

Non-Office 

Skylight Area (ft2)

Office Skylight Area 

(ft2)

Annual Electric 

Savings 

(kWh/year)

Daylighting Captial 

Cost ($)

Daylighting 

Annual Cost 

Savings ($/year)

Daylighting 

Payback Period 

(years)

99,123 0 2,092,540 $4,320,360 $377,745 11.4 

Recommendations

The analysis for daylighting only considered warehouse type buildings and offices. We did not 

include housing. NREL generally does not recommend retrofitting daylighting in most existing 

buildings as it is not cost-effective. There are retrofitting opportunities in warehouse-type 

buildings because roofs are often metal and uninsulated. Daylighting, however, can be 
27

incorporated at no additional cost in the design stage of a building, so we recommend that all 

new construction at MCBH Kaneohe Bay incorporate daylighting strategies.

5.6 Photovoltaic

Technology Overview PV

Photovoltaics (PV) are semiconductor devices that convert sunlight into electricity. They do so 

without any moving parts and without generating any noise or pollution. They must be mounted 

in an unshaded location: rooftops, carports and ground-mounted arrays are common mounting 

locations. They are very reliable and last 20 years or longer. 

The amount of energy produced by a panel depends on the efficiency. This depends on the type 

of collector, the tilt and azimuth of the collector, the temperature and the level of sunlight. An 

inverter is required to convert the direct current (DC) to alternating current (AC) of the desired 

voltage compatible with building and utility power systems. The balance of the system consists 

of conductors/conduit, switches, disconnects, and fuses. Grid-connected PV systems feed power 

into the facility’s electrical system and do not include batteries. Figure 14 shows the major 

components of a grid-connected PV system and illustrates how these components are 

interconnected in a grid-connected PV system.

Figure 14. Depiction of major components of grid-connected PV system

Source: Jim Leyshon (NREL)

PV systems can be sized to meet almost any load since they are modular systems consisting of 

strings of interconnected panels. The cost-effectiveness of grid-connected PV systems depends 

largely on the solar resource and the incentives offered.
28

Planned PV Projects

MCBH Kaneohe Bay provided NREL with the proposed sites for solar PV projects (see 

Appendix C). These sites include selected carports and rooftops areas. Over 24 carports were 

selected as potential sites for PV. The estimated power production from these sites is 2.72 MW.

The total estimated rooftop area is 745,066 ft2 with estimated power production calculated to be 

~7.45 MW peak. The total amount of power that can be generated from the selected carports and 

rooftop sites is ~10.2 MW peak.

Economic Analysis

For the economic analysis, the Hybrid Optimization Model for Electric Renewables 

(HOMER) tool was used. NREL modeled 10 MW of PV with the following capital and 

maintenance costs listed in Table 10, and the simple payback calculated in Table 11. 

Table 10. PV Capital and Maintenance Costs

Quantity Capital ($) Replacement ($) O&M ($/yr)

1 MW 6,000,000 5,000,000 5,000

Table 11. PV Economic Analysis

Metric Value

Net Present worth $ -28,035,740

Annual worth $ -2,193,144/yr

Return on investment 4.23 %

Simple payback 24.9 yrs

Discounted payback n/a

Recommendations

MCBH Kaneohe Bay has a number of potential sites for PV installation on ground areas, 

rooftops, and carports. Ground mount systems generally have the best payback period therefore 

we recommend pursuing these opportunities first. MCBH Kaneohe Bay has outlined a Power 

Purchase Agreement (PPA) and request for proposal (RFP) with a phased award plan for all their

PV projects. The PV sites and approximate available areas for each task order are in the plan. 

There are five task orders in the phased award plan. MCBH Kaneohe Bay may also be able to 

fund individual rooftop systems through Army Corps of Engineer building funds. 

5.7 Concentrating Solar Power

Technology Overview

Electricity and useful heat can be produced through a solar thermal process using concentrating 

solar power (CSP). Collectors focus solar heat onto a fluid, the heat creates steam, which turns a 

turbine or engine attached to a generator to create electricity. CSP requires direct solar radiation 

and cloud cover greatly impacts the power output. Motors and controls track the sun. Although 

these systems include minimal moving parts, they do require preventative and unscheduled 

maintenance. The most common power production technologies are dish Stirling engines,

parabolic troughs, and power towers which use heliostats to focus sunlight on a tower-mounted 

receiver.
29

NREL has developed a database (http://www.nrel.gov/csp/solarpaces) of worldwide CSP 

projects either operational, under construction, or under development. There are approximately 

fifty parabolic trough systems included in the database. World-wide there are a few smaller, 

distributed generation scale parabolic trough systems (1 to 5 MW scale), however the vast 

majority of the systems are 50 MW and larger. The small scale systems are either proof of 

concept or tied directly to existing power plants to supplement other conventional fuel-powered 

plants. Dish Stirling systems may be more appropriate for distributed generation and there are a 

few manufacturer’s working in this space (10 kW and 25 kW), however the technology is precommercial. The NREL database includes only two dish Stirling systems.

Existing or Planned Projects

There are no existing or planned CSP projects at the MCBH Kaneohe Bay. 

Economic Analysis

The great majority of commercially operating CSP systems are utility scale, 50 MW to 1,000 

MW. A few projects of 5 MW in size and smaller have been deployed or are in planning but 

capital and operation and maintenance costs cannot be readily determined nor reasonably applied 

to potential projects at MCBH Kaneohe Bay. 

Recommendations

For distributed generation, CSP is pre-commercial and not appropriate for consideration as a 

proven, reliable technology for MCBH Kaneohe Bay deployment. The MCBH Kaneohe Bay 

should consider participating in CSP proof-of-concept or field trials if presented with an 

opportunity that does not require financial backing of the base or commitment to long term 

contracts.

5.8 Wind Turbines

Technology Overview

Wind turbines consist of rotating blades that convert the momentum of the wind to electric 

power. They have several moving parts and require regularly scheduled and unscheduled 

maintenance. Turbines are available from as small as 250-watt to as large as 5 MW, with the 

larger wind turbines being most economical. Wind turbines work best when installed in areas of 

wide open space.

Some of the challenges as wind turbines get larger are deploying them to the island nations. 

Roads and transmission infrastructure are often not available at the sites. The blade sizes are 

often too large for transporting into remote areas on small roads. Cranes are often required to 

mount the wind turbine and perform maintenance. Installation and maintenance can increase the 

cost dramatically for wind turbines in Hawaii. 

A new technology that is being used in the Caribbean is a wind turbine designed by a French 

company, Vergnet. The turbine is a small light weight wind turbine with a two blade rotor –

teetering hub, light foundations, and guyed tower. These wind turbines can be lowered to protect 

them during hurricanes. Traditional turbines on the other hand use three blade rotors, a heavy 

tower, and large, deep foundations. The Vergnet are smaller units (275 kW – 1 MW) compared 

with 2 to 5 MW traditional wind turbines.
30

Figure 15. Vergnet 275 kW wind turbine (2 blades)

The cost of wind technology decreased sharply in the 1990s but then began to increase in 2006 

due to increasing cost of materials (copper, steel and concrete) and market demand.

Figure 16. Cost curve for Wind Technology 

Existing or Planned Projects

The only planned wind turbine at this time is a small 2.4 kW Skystream turbine being installed at 

the school. Initial screening suggests MCBH Kaneohe Bay’s strong wind resource could result in 

wind turbine capacity factors of 30 – 35%. 

Economic Analysis

The economics are highly favorable for wind turbines. A 1.5 MW turbine was modeled in 

HOMER with the cost assumptions shown in Table 12. The number of wind turbines needed to 

offset all the on-site electricity is 19 for a total of 28.5 MW. The economics in Table 13 show a 

favorable payback of 2.78 years. 
31

Table 12. Cost for a 1.5 MW Wind Turbine

Quantity Capital ($) Replacement ($) O&M ($/yr)

1 3,500,000 2,500,000 200,000

2 6,000,000 5,000,000 250,000

Table 13. Economics for 27 MW Wind Farm

Metric Value

Present worth $ 168,389,744

Annual worth $ 13,172,577/yr

Return on investment 35.1 %

Simple payback 2.78 yrs

Discounted payback 3.13 yrs

Recommendations

MCBH Kaneohe Bay should consider installing wind turbines on their base; see Appendix D for 

wind resource and potential sites. Large wind turbines could significantly reduce their electrical 

use, and could possibly bring the MCBH Kaneohe Bay to net zero depending on how large a 

wind farm could be installed. An interconnection study would need to be done. HECO has 

limitations on how much power can be sold back to the grid. If there is an excess MCBH 

Kaneohe Bay could use the energy in their electrolysis process and create hydrogen that can be 

stored for their planned hydrogen fleet or to possibly run a fuel cell for backup power. Using 

excess wind or solar energy to produce hydrogen is being studied extensively as a way to store 

excess renewable energy.9

5.9 Fuel Cell

Technology Overview

Fuel cells offer another option for generating power at MCBH Kaneohe Bay. Fuel cells have 

high efficiency and low emissions in comparison with other conventional cogeneration systems. 

There are several different types of fuel cells, such as phosphoric acid, proton exchange 

membrane (PEM), solid oxide, and molten carbonate. The fuel source for these cells is typically 

hydrogen or a methane-based fuel, such as natural gas or renewably derived biogas. Electricity 

and heat produced from fuel cells is considered renewable energy when produced from a 

renewable biogas or hydrogen. Fuel cell systems are sized based primarily on the thermal load 

that can be displaced in a particular area. The electrical energy produced by the fuel cell would 

be put into the base distribution network and could be utilized anywhere on base; however, the 

thermal load must be used on site. Housing areas, with their high space-heating and domestic hot 

water needs, are prime candidates.

During a grid outage, the fuel cell power plant disconnects from the utility grid in milliseconds 

and then continues to produce power to serve the customer’s critical loads. This “island” 

operation would strictly serve dedicated loads (as well as the loads of the fuel cell system itself),

without allowing any power to be exported to an otherwise unpowered utility grid. After power 

returns to the utility grid and is stable, the fuel cell is designed to automatically synchronize its 

power to the grid, while providing continuous power to the critical loads. If critical backup is not 

 9 K.W. Harrison, G.D. Martin, T.G. Ramsden, and W.E. Kramer; The Wind-to Hydrogen Project: Operational 

Experience, Performance Testing, and Systems Integration., NREL/TP-550-44082, March 2009.
32

required by the customer, then the fuel cell power system uses island mode to maintain power for 

its own process loads and remains ready for reconnection to the utility grid on return of live-grid 

power. 

Planned Projects

In 2005 or 2006, fuel cells were installed at a few bases in Hawaii including MCBH Kaneohe 

Bay as part of a pilot study. NREL gathered from talking with the staff at MCBH Kaneohe Bay

that there were problems with the fuel cell and it was often down for maintenance. Thus, MCBH 

Kaneohe Bay is not looking into installing fuel cells at the present time. Fuel cell technology has 

improved significantly in the past three years and MCBH Kaneohe Bay may want to reconsider 

fuel cells as an alternative power plant in conjunction with their on-site hydrogen production. 

Economic Analysis

The electrolyzer that is being installed in MCBH Kaneohe Bay is for a 350-bar vehicle filling

station. An additional 700-bar filling station will be installed in 2012. According to the Hawaii 

Natural Energy Institute, the approximate power consumption of the components are: 

• Electrolyzer – 82 kWh/kilogram(kg)H2

• 350-bar compressor (10 HP) – 8 kWh/kgH2

• 700-bar compressor (40 HP) – 10 kWh/kgH2

The electrolyzer produces 1 kg of hydrogen per hour which is approximately 168 kg of hydrogen 

per week. This is a small electrolyzer to supply hydrogen to their fuel cell fleet. They currently 

have three sedan-type vehicles that use around 12 kg of hydrogen per week and are planning to 

increase the number of fuel cell vehicles in the future.

To accommodate a large fuel cell for an alternative power plant, MCBH Kaneohe Bay will need 

to look at industrial scale components. The electrolyzer for large scale production would need to 

produce 1,000 kg/day and would cost ~$2 million. These units take ~54 kWh of electricity to 

produce 1 kg of hydrogen. Two manufacturers make units of 1,000 kg/day or (~2250 kW). The 

efficiency of the units is 62%. The utility scale electrolyzer could supply a fuel cell enough 

hydrogen to produce ~1.5 MW of electrical power. This is assuming that the when excess 

renewable energy from wind and solar is available, the the power is used to run the electroyzer,

and the fuel cell is off. When the renewables are not available, the fuel cell operates, and the 

electoyzer is off. Hydrogen storage is ~$1,000/kg and is assumed to be sufficient for the 

calculations. The entire system of this size would cost ~$10 million. The calculations with 

assumptions are presented in the Table 14 below.

It is important to pause before deciding what to do with the hydrogen. There are three options at 

this point:

• Sell the hydrogen as merchant hydrogen

• Use the hydrogen to refuel vehicles

• Use the hydrogen to produce electricity.
33

From past analysis the most economic option is to refuel cars and busses. This does not 

contribute to on-site emission reductions, but does help with scope-3 emissions (which includes 

transportation). It would be prudent to evaluate how much hydrogen could be used for 

transportation before using the remainder for power production.

Power generation with fuel cells at the MW scale was demonstrated for the first time last year by 

Ballard Power, in conjunction with a large energy utility company. It is not certain what their 

costs would be for the next iterations of their design. The units will be available in 1 MW and 

500 kW increments.

10

As mentioned in the technology overview for fuel cells of this report, the power generation from 

fuel cells is capable of near-instantaneous response in demand change. Using a large, utilityscale system, can offer voltage and frequency control to balance MCBH Kaneohe Bay load 

dynamics and renewable power. The fuel cell could also be useful for load management.

Table 14. Electrolyzer and Fuel Cell Calculations

PARAMETER VALUE Units of 

Measurments

NOTES

Electrolyzer

Electrolyzer size 2250 kWe This variable can be 

adjusted

Production electricity use 54 kWhe/kgH2

Electrolyzer production 41.67 kg H2/h

Electrolyzer operating fraction 65% % of time When renewables are available, electrolyzer operates, and the fuel cell is 

off. 

Average week electrolyzer operating 

hours

 

109 

hours/week

Fuel Cell

Average week H2 production 4550.0 kg/week

Fuel cell operating fraction 35% % of time When renewables are not available, FC works and 

ELZR stops.

Average week fuel cell operating 

hours

 

59 

hours/week

Fuel cell hydrogen consumption rate 

77.38 

kg/hour

Fuel cell average power output 1599.53 kWe Assumes fuel cell is 62% efficient and 33.34 kg/kWh

Storage

Largest window of zero renewables 48 hours This variable can be 

adjusted

Minimal hydrogen storage required 

3,714.29 

kg

Costs

Electrolyzer 2000000 $ Assuming electrolyzer cost $2 M

Storage 0 $ Assuming storage is already 

sufficient

Fuel cell 

9,997,631 

$

 10 Ballard Power, http://www.ballard.com/
34

5.10 Landfill Gas

Technology Overview

It is also possible to generate energy through the anaerobic decomposition of carbon-based waste 

streams deposited in a landfill. Landfill gas is primarily composed of methane and carbon 

dioxide. Typically, a gas handling system at the landfill traps, collects, and transports the gas 

produced. It is often necessary to clean landfill gas prior to combustion in order to remove 

potentially hazardous compounds such as sulfur. Once a landfill is capped and closed off, it will 

continue to produce gas for 15-20 years. 

A good candidate for landfill gas collection should have at least 1 million tons of waste in place, 

be at least 30 feet deep, and be active or recently closed. It should also have a high organic 

content, because non-organic waste does not break down and emit methane. 

Analysis

During the site visit, the NREL team discussed landfill use with the MCBH Kaneohe Bay energy 

team. MCBH Kaneohe Bay has two landfills on site that are primarily composed of construction 

and demolition (C&D) waste. The C&D landfills are not appropriate for landfill gas collection 

because most of the waste is not organic. 

MCBH Kaneohe Bay should consider looking at landfills offsite. Offsite landfills would not 

provide an onsite source of renewable energy, however, if landfill gas were generated at these 

sites, it could be stored, transported, and used instead of propane gas. MCBH Kaneohe Bay

could then utilize the renewable landfill methane gas. This arrangement would provide a 

renewable fuel source for MCBH Kaneohe Bay’s boilers. 

Recommendations

We recommend discussing offsite landfill gas generation projects with the utility that provides 

the propane and local landfill owners to evaluate whether local landfills are appropriate for 

landfill gas systems and if it is feasible to pipe gas to MCBH Kaneohe Bay.

5.11 Anaerobic Digestion

Technology Overview

Anaerobic digestion is the conversion of wet biomass feedstocks such as confined animal waste, 

industrial effluent, or wastewater, to methane fuel. Because of its high water content, it is not 

efficient to transport wet feedstocks. Instead, they must be converted on site where they are 

generated.

Analysis

MCBH Kaneohe Bay owns an anaerobic digester that is located at their wastewater treatment 

plant. ,The size of the digester is 36,800 cubic feet. The anaerobic digester is not in service at this 

time but it has the potential to produce 116 kW. This small generator could produce ~1 MWh of 

energy each year and save MCBH Kaneohe Bay $203,365/year in utility costs.

Like the landfill gas discussed earlier, it might be possible to look off base at the nearby waste 

water treatment plant for the area and treat the methane gas and have MCBH Kaneohe Bay

purchase it to displace conventional propane. This arrangement would provide a renewable fuel 

source for MCBH Kaneohe Bay’s boilers or future fuel cells.
35

Recommendations

We recommend discussing offsite methane gas generation projects with their propane provider 

and the City of Kaneohe Bay.

5.12 Hydropower/Ocean Wave Energy

There is a small demonstration project presently installed at MCBH Kaneohe Bay for Ocean 

Wave Energy. The company, Ocean Power Technologies, is testing their model PowerBuoy 

shown in Figure 17. The device converts wave motion into electricity with a moored buoy that 

floats freely up and down in the water. A structure with a piston moves as the PowerBuoy bobs 

in the waves. This movement drives a turbine and electric generator. The PowerBuoy installed 

at MCBH Kaneohe Bay is tied to the grid and rated at 40 kW. Present reports given to the 

electrical engineering staff at Kaneohe indicate that the PowerBuoy generates less than 10 kW. 

Figure 17. PowerBuoy

Source: Ocean Power Technologies, Inc.

Recommendations

We recommend MCBH Kaneohe Bay continue to participate in pilot demonstrations of new 

technologies. This will help accelerate the market development of cutting edge renewable energy 

technologies.

5.13 Hybrid System Optimization

Renewable Energy Hybrid Systems

Based on the initial REO analysis and the technologies that looked most feasible (PV and wind 

turbines) NREL ran a more detailed analysis using the software modeling tool, HOMER.

11 We 

took hourly load data for MCBH Kaneohe Bay from 2009 along with hourly wind data 

monitored from the site, and hourly solar resource data from the NASA website. HOMER 

calculates the optimal solution to meet the electrical load for each hour at the lowest net present 

cost. We ran two scenarios in HOMER:

 11 HOMER Energy LLC, Hybrid Renewable and Distributed Power Design Support. http://homerenergy.com/
36

• Wind/ Grid Net Metered: This analysis identifies the total wind turbine capacity needed 

so that MCBH Kaneohe Bay generates as much electrical energy as it uses on an annual 

basis to be net zero electrical energy consumption.

• PV/Wind/ Grid Net Metered: This analysis identifies the best mix of PV and wind such 

that the PV and wind turbines generate as much electrical energy on site as MCBH 

Kaneohe Bay uses on an annual basis.

Wind Turbines/Grid Net metered 

NREL analysis shows that it is possible for MCBH Kaneohe Bay to become a net-zero electrical 

energy site with a wind turbine/grid system. 28.5 MW of wind turbines will generate as much 

energy as MCBH Kaneohe Bay uses on an annual basis. When the wind turbines are producing 

more energy than the site needs, excess energy will be sold back to the grid. When they are 

producing less energy than the site needs, energy will be purchased from the grid. With 28.5 

MW of wind turbines, there is enough excess energy produced onsite and sold back to the grid to 

make it a net-zero electrical energy installation. 

The modeling cost assumptions are listed in Table 12 above. The expected lifetime of a wind 

turbine is 20 years. The optimal wind turbine/grid tied system is summarized in Table 15, 16,

and 17. The levelized cost of energy is reduced from $0.20/kWh to $0.05/kWh, a 75% reduction. 

Figure 18 illustrates the monthly average electric production from wind and purchased from the 

grid. The results indicate that wind power is likely a cost-effective option. The total installed 

capacity that the site could support would need to be further studied and depends on, among 

other things, siting constraints, electrical system infrastructure issues, utility interconnection 

rules, and net-metering limits.

Table 15. Wind Turbine/Grid Hybrid System

Component

Wind Turbines 19 (1.5 MW each) 28.5 MW

Utility Cost $0.20/kWh

Levelized Cost of Energy of Wind/Grid System $0.05/kWh

Table 16. Wind Turbine/Grid Annual Energy Production

Production kWh/yr %

Wind turbines 92,879,232 74

Grid purchases 32,200,204 26

Total 125,079,440 100

Table 17. Wind Turbine/Grid Annual Grid Sales

Consumption kWh/yr %

Kanehoe Bay load 88,928,208 71

Grid sales 36,151,164 29

Total 125,079,376 100
37

Figure 18. Monthly average electric production

Table 18 compares commercially available turbines to examine how many turbines will be 

required for a wind-only NZEI. There is a significant constraint as to where turbines could be 

placed and larger machines will require fewer sites and less land.

The number of turbines and land required for a full NZEI using only wind varies widely. 

Available land area should be considered when making a turbine choice. Potential sites for wind 

turbines within MCBH Kaneohe Bay are shown in Appendix D.

Table 18. Wind Turbine Technology and Estimated Number of Turbines for NZEI

Turbines Hub

Height

(m)

Wind 

Speed

(m/s)

Time A

Zero 

Output

(%)

Time 

At

Rated 

Output

(%)

Mean 

Net

Power 

Output

(kW)

Mean Net

Energy 

Output

(kWh/yr)

Net 

Capacity

Factor

(%)

Number 

of 

turbines

required 

for NZE

GE 1.6-100 80 7.08 10.25 7.04 777.6 6,812,106 48.6 13

GE 1.6-82.5 80 7.08 10.26 3.23 614 5,378,799 38.4 16

REpower MM92 80 7.08 7.68 4.85 859.2 7,526,912 41.9 12

Siemens SWT-2.3-101 80 7.08 10.25 1.25 928 8,129,035 40.3 11

Vestas V100 - 1.8 MW 80 7.08 10.07 3.71 866 7,586,233 48.1 13

Vestas V100 - 2.0 MW 80 7.08 9.74 0.03 873 7,647,703 43.7 11

Vestas V100 - 2.6 MW 75 7.05 9.94 0.05 901.4 7,896,506 34.7 11

Vestas V112 - 3.0 MW 84 7.11 7.45 3.4 1,220.60 10,692,560 40.7 8

Vergnet GEV HP 70 7.01 10.7 0.04 316.9 2,775,885 31.7 31

All of the above turbines are applicable for the wind resource and assumed extreme winds at 

Kaneohe. Some manufacturers may not warranty their turbines in this location due to cyclone 

exposure. Not all turbines are guaranteed available for use on this project. An economic 

optimization for turbine selection should be performed to capture O&M, balance of plant, 

delivery, installation, and costs.

PV/Wind Turbines/Grid Net metered 

Similar analysis was done to see how 10 MW of PV can affect the hybrid mix of generation for a 

NZEI and the levelized cost of energy. The PV size was limited to 10 MW, which is the expected 
38

amount of PV presently being planned at MCBH Kaneohe Bay. PV was modeled with the 

following cost assumptions:

Table 19. PV Modeled Cost

Size (kW) Capital ($) Replacement ($) O&M ($/yr)

1000 6,000,000 5,000,000 5,000

On an annual basis, with 24 MW of wind and 10 MW of PV, there is enough excess energy 

produced onsite and sold back to the grid to make it an NZEI. The modeling cost assumptions 

are listed in Table 10 above. The expected lifetime of a wind turbine and PV system is 20 years. 

The optimal wind/PV/grid tied system for an NZEI is summarized in Table 20, 20, and 21. The 

levelized cost of energy is reduced from $0.20/kWh to $0.09/kWh, a 55% reduction, and the 

renewable energy fraction at MCBH Kaneohe Bay is 78%. 

Table 20. Wind Turbine/PV/Grid Hybrid System

Component

PV array 10.0 MW

Wind Turbines 16 (1.5 MW each) 24.0 MW

Utility Cost $0.20/kWh

Levelized Cost of Energy of 

Wind/PV/Grid Hybrid System

$0.09/kWh

Table 21. Wind Turbine/PV/Grid Annual Production

Production kWh/yr %

PV array 15,432,643 13

Wind turbines 78,213,952 65

Grid purchases 26,186,056 22

Total 119,832,648 100

Table 22. Wind Turbine/PV/Grid Annual Grid Sales

Consumption kWh/yr %

AC primary load 88,928,208 74

Grid sales 30,904,518 26

Total 119,832,728 100
39

Figure 19. Monthly average electric production

Recommendations

The renewable energy analysis indicates that the installation of 28.5 MW of wind generation is 

the most cost effective means of obtaining net zero electricity. Adding the planned 10 MW of PV 

or more would further increase MCBH Kaneohe Bay’s onsite production and reduce the amount 

of electricity purchased from the grid. Though adding PV to the hybrid solution for NZEI 

slightly increases the levelized cost of energy, the PV will diversify the power generation. Often,

there is wind resource at night when solar resource is not available complimenting the solar 

production.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 0

5,000

10,000

15,000

20,000

Power (kW)

Monthly Average Electric Production PV

Wind

Grid
40

6 Transportation Assessment

NREL personnel visited MCBH Kaneohe Bay in early 2010 and were able to obtain basic 

information about MCBH Kaneohe Bay’s fleet fuel consumption including a fleet list and 

estimated driving usage, however, we did not obtain the commuting patterns of staff. NREL is 

presently working with the energy management team at MCBH Kaneohe Bay to complete this 

analysis. In March, when NREL visited MCBH Kaneohe Bay, it was brought to our attention 

that a portion of their fleet is being converted to hydrogen vehicles by 2015. The data gathering 

and analysis is presently being updated. 

6.1 Analysis

Although MCBH Kaneohe Bay’s fleet fuel consumption is a small component of fuel 

consumption at MCBH Kaneohe Bay, it is relevant because this fuel is subject to various 

statutory and Executive Order (EO) requirements, including EO 13423, EPAct 2005, and EO 

13514. As fleet fuel consumption data was available, NREL was able to establish a NZEI 

transportation baseline for the fleet, see Table 23. Note: JP-8 is for tactical use and is not part of 

the baseline.

Table 23. Fuel Use Baseline, MCBH Kaneohe Bay

Baseline Annual Fuel Usage Information

Total Gasoline (gallons) 181,802

Total Diesel (gallons) 93,967

Total JP-8 (gallons) 9,335,777 

MCBH Kaneohe Bay recently provided information indicating that both an E85 and B20 

refueling pumps were installed on base in summer 2011. MCBH Kaneohe Bay is moving quickly 

to transform their fuel use. Biodiesel B20 is currently used in MCBH Kaneohe Bay diesel-fueled 

vehicles such as buses. Diesel vehicles are generally capable of using biodiesel fuel, so biodiesel 

likely represents the best option for alternative fuel use at MCBH Kaneohe Bay, especially 

considering NREL’s baseline calculations indicate that the majority of fleet fuel is consumed in 

MCBH Kaneohe Bay heavy-duty tanker trucks and tractor-trailers. Generally, dispensing 

equipment does not need to be modified for blends of 20% biodiesel or lower, although tank 

cleaning is recommended when switching to B20 fuels. The dispensing systems will not need 

protection from freezing in Hawaii. 

Transform MCBH Kaneohe Bay’s Vehicle Inventory

MCBH Kaneohe Bay’s vehicle inventory should be transformed by “rightsizing” the overall 

fleet, and ensuring that the right type of vehicles is in the fleet. “Rightsizing” can be

accomplished by adopting a car pool approach, and includes eliminating excess vehicles. 

Eliminating most of the vehicles that are driven less than 50 miles per month would be a good 

start. Additionally, it is recommended that MCBH Kaneohe Bay look for opportunities to 

transform fleet composition. MCBH Kaneohe Bay has indicated that replacing light-duty trucks 

and SUVs with light-duty cars is not a feasible option due to the rough terrain at the base; but 

adopting smaller and/or more fuel-efficient vehicles (e.g., using two-wheel drive rather than 4x4 

pick-ups, or vehicles with a V6 versus a V8 engine, depending on the mission of these vehicles) 
41

may be an alternative. Since MCBH Kaneohe Bay has installed E85 and biodiesel refueling 

infrastructure on-site, it is important that the base acquire vehicles that can use these types of fuel 

and institute policies that support the use of alternative fuel in AFVs (e.g., requiring that lightduty diesel trucks use biodiesel exclusively). Decision-assisting guidance that might look 

something like the following might be helpful, and could be applied to every vehicle in MCBH 

Kaneohe Bay’s fleet.

 Does the vehicle need to exist? If the vehicle is a low mileage vehicle, consider getting 

rid of it and using a pool approach.

 If the vehicle is required, can it be a neighborhood electric vehicle (NEV) or some other 

type of smaller electric vehicle?

 If a NEV is not acceptable, can the vehicle be an HEV? 

 If the vehicle cannot be a HEV, can it be a diesel vehicle and use biodiesel fuel?

At the least, replacing older, less fuel-efficient gasoline-fueled vehicles with vehicles that have

better fuel economies would be a strategy to consider as well.

Use Alternative Fuel

NREL recommends that MCBH Kaneohe Bay fully commit to B20 use 100 percent of the time 

in its diesel vehicles. This will require MCBH Kaneohe Bay to work with its diesel supplier to 

obtain B20. Mixing diesel fuel and biodiesel fuel in engines and storage tanks will have adverse 

affects on diesel vehicle performance, so fleet users should avoid mixing biodiesel and diesel in 

both vehicle engines and thoroughly clean storage tanks before replacing diesel with biodiesel. If 

poor results with biodiesel use are experienced, consider switching fuel suppliers. Biodiesel 

specifications are in place that guarantee a certain quality of biodiesel fuel; so diesel vehicles at 

MCBH Kaneohe Bay should perform as well using biodiesel fuel as they would if they were 

using diesel fuel.

These measures would help MCBH Kaneohe Bay work toward petroleum reduction 

requirements under EO 13514, EPAct 2005, and EO 13423 and begin developing a culture that 

emphasizes the use of alternative fuels.

The recent addition of an E85 fueling station to MCBH Kaneohe Bay gives the base the ability to 

replace a large portion of the fleet’s fossil fuel with ethanol. The general composition of the fleet 

and an estimate of fleet gasoline usage was obtained by NREL and was used to estimate the 

gasoline savings that could be achieved by switching certain classes of fleet vehicles over to E85. 

By phasing out gasoline-powered vehicles for E85 vehicles, the fossil fuel savings are shown in 

the table below.
42

Table 24. Gasoline Savings for Changing to E85 

Percentage of light/medium duty 

vehicles changed to E85

Gasoline Reduction 

(Gallons/year)

10% 6,303

20% 12,606

50% 31,514

80% 50,423

100% 63,029

Hydrogen used in conjunction with fuel cell vehicles gives the base the ability to produce its own

fuel without relying on infrastructure. At the moment, hydrogen vehicles are prohibitively 

expensive, but if prices fall, MCBH Kaneohe Bay may want to consider changing over to 

hydrogen fueled vehicles since they will be generating their own fuel primarily from renewable 

technologies. The potential gasoline savings from changing a percentage of light and medium 

duty vehicles to hydrogen is shown in the table below. 

Table 25. Gasoline Reduction for Changing to H2 

Percentage of 

light/medium duty 

vehicles changed to H2

Gasoline 

Reduction 

(Gallons/year)

10% 7,878

20% 15,757

50% 39,392

80% 63,028

100% 78,785

NREL understands that MCBH- Kaneohe Bay is converting some of their fleet to new hydrogen 

fueled vehicles. They are also procuring electrolysis equipment to produce hydrogen on site. 

The hydrogen vehicle fleet is presently three sedans that use ~4 kg of hydrogen per tank and 12 

kg/week. The electrolysis equipment produces 1 kg/ hr or 168 kg of hydrogen per week. If the 

price comes down on hydrogen vehicles an additional 13 sedans could be purchased to replace 

gasoline vehicles.

6.2 Additional Strategies to Reduce Load and Footprint

Tactical Fuel Use Reduction

Tactical fuel use accounts for the majority of all transportation-related fuel use at MCBH 

Kaneohe Bay, and a significant component of total energy use at MCBH Kaneohe Bay as well. 

Clearly, any reasonable efficiency analysis should at least consider tactical fuel use. NREL staff 

believe that the potential exists for reduced tactical fuel use. The emphasis of this analysis is not 

necessarily displacing tactical fuel with a bio-based fuel; but rather through adopting 

efficiencies.
43

NREL recommends that MCBH Kaneohe Bay conduct additional analysis on the potential for 

reduced tactical fuel use based on efficiencies. Some NREL staff associated with the MCBH 

Kaneohe Bay analysis are ex-military officers and/or have supported DOD extensively in the 

past, and they understand the unique challenges and opportunities faced by the military services. 

Biodiesel and Biomass Based Jet Fuel

The potential use of tactical fuel manufactured from biomass sources presents an opportunity for 

MCBH Kaneohe Bay. As discussed in the fleets section, the use of biodiesel may be an option 

for reducing diesel consumption, as long as tanks and vehicles are dedicated to biodiesel use. 

Additionally, several military and commercial demonstration projects of biologically-based 

aviation fuels are currently underway. However, at this point there is no commercially available 

and affordable option to replace tactical aviation fuel derived from petroleum with a fuel derived 

from biomass products. MCBH Kaneohe Bay should monitor the technical development of the 

demonstration projects and look for opportunities to reduce its footprint with a biomass based jet 

fuel as soon as feasible.

Fuel Delivery Systems Efficiency

MCBH Kaneohe Bay should examine efficiency of its fuel distribution system. Since the base 

consumes about 9,335,777 gallons of fuel annually the fuel distribution system should be 

analyzed to make sure that tanks and pipelines are performing optimally. 

Commuter Fuel Use Reduction

Changing commuter behavior is a difficult challenge, since often there is little flexibility in the 

number of trips required to and from work, and the number of miles required to drive to reach 

work. Even so, the following are a few recommendations for MCBH Kaneohe Bay to consider in 

an attempt to reduce commuter fuel consumption and associated GHG emissions.

• Alternative Work Schedules: MCBH Kaneohe Bay employees may be able to engage in 

alternative work schedules. For example, it is not uncommon for some employees to 

work nine hours per day (rather than eight) and to take every other Friday off, or to 

telecommute occasionally. These types of policies have the potential to greatly reduce 

commuter fuel use.

• Ride Sharing: NREL recommends that MCBH Kaneohe Bay encourage its staff to 

participate in ride-sharing programs, and, if possible, extend the use of van-pooling to 

areas that are not currently covered. One approach is to e-mail all employees asking for 

volunteers of who might be interested in sharing rides to and from work. Interested 

parties would provide their address information, and would be matched with other 

personnel living nearby. A second approach is to incentivize vanpooling by offering 

vouchers to pay the fare of employees who participate in official vanpools. For example, 

NREL’s Vanpool Incentive Program provides monthly vouchers for up to $200 to pay the 

fair of vanpooling employees.

• Shuttles: Another possible way to reduce employee commuting is for MCBH Kaneohe 

Bay to provide commuter shuttles between MCBH Kaneohe Bay and areas of high 

employee concentration, such as Honolulu. Shuttles provide an excellent opportunity to 

reduce commuter fuel consumption. Available advanced vehicle options include diesel 
44

hybrid electric and plug-in diesel hybrid electric. Shuttles can also be operated using 

alternative fuel such as propane or biodiesel. 

NREL staff did not attempt to quantify the number of personnel at MCBH Kaneohe Bay who 

might be interested in alternative work schedule arrangements or additional ride-sharing. 

However, if MCBH Kaneohe Bay were able to reduce commuter travel by 5 percent, 9,090

gallons of petroleum use would be eliminated. 
45

7 Electrical Systems Assessment and Recommendation

7.1 Electrical Distribution System Overview

MCBH Kaneohe Bay is served by Hawaii Electric Company (HECO) at a single substation. 

Transmission is via a 138-kilovolt (kV) line with two 46-kV feeders to the three transformers in 

the main substation. The three HECO transformers have 12.5 MVA capacities. Figure 20

illustrates the MCBH Kaneohe Bay electrical one-line diagram provided by the MCBH Kaneohe 

Bay energy staff.

C

O O O

C C

C

O

C C

C

C

XFMR

#1

XFMR

#2

XFMR

#3

B5033

HECO XFMR’s 1,2 & 3 are 10 (12.5) 

MVA capacity each (FA/FO)

HECO 46 KV

Koolau-Aikahi 

Circuit

HECO 46 KV

Koolau-Kailua 

Circuit

C

C

C C =Normally Closed

O =Normally Open

=Energized feeder

=De-energized feeder

=Alternate feeder

## =Critical Asset

12/8/08

O

MCBH ELECTRICAL ONE-LINE

A BUS B BUS C BUS

Legend

C

150 250

350

200 A 510 A

1B

100 200 300

3B 1A 2B 1B 

B5092

A BUS B BUS C BUS 150 250 350

100 200 300

3-1A 3-2A 3-2A 3-4A 3-4B 3-3B 3-2B 3-1B 12-1 12-2A 12-3 12-4 12-2 101 106 104 107 105 103 102

3A T3-2 3B T3-1 2A 2B T2-3 T2-1 T1-2 1A 1B T1-3

290 A

2A 3A

Sub 

#1

Sub 

#2

Sub 

#3

Main 

Sub

B820 B1125

1

11 12

10 7 8 9

4 5 6

3

2

20

17 18 19

14 15 16

13

26 27 28

23 24 25

21 22

Figure 20: MCBH Kaneohe Bay single line electrical drawing

There are three substations that are fed from the main substation. Substation 1 is in building 1125 

and distributes power to the east side of the base which includes the housing district and supports 

approximately half the base load. Substation 2 is housed in building 820 and provides service to 

the central part of the base including many of the operations facilities. Substation 3 is located in 

building 5033 and provides power to the airfield and tactical facilities.
46

7.2 Impact Analysis of Distributed Generation

The output of the PV array and wind turbines will be stepped up via separate transformers that 

tie into the 12.47-kV primary distribution system. The higher voltage (69 kV) is considered (sub) 

transmission level and supplies the substation transformer. Transmission lines are typically not 

accessible to renewable energy system operators for safety reasons and utility operating 

requirements. Voltage connection levels are dictated by the existing utility system. Large 

distributed generation (DG) systems generally interconnect onto the distribution system and then 

tie back to a substation which is fed by a transmission line. 

To maintain the integrity of the reconfigurable distribution system, each feeder must not only be 

able to support the DG that is proposed to be connected to that feeder, but it must also be able to 

support the DG that could be switched onto the feeder via reconfiguration. 

7.3 Interconnection 

This section of the report primarily focuses on the interconnection of proposed large wind 

turbines into the existing electrical infrastructure at MCBH Kaneohe Bay. The interconnection 

for the planned PV projects (carports, ground mount, and rooftops) was not analyzed in detail 

here since the individual distributed generation sizes are not as significant as the wind farms. 

Each task order for PV projects will need to evaluate the proposed interconnection. 

MCBH- Kaneohe Bay constraints

The existing electrical infrastructure at MCBH Kaneohe Bay does not present large opportunities 

to integrate the full 20-30 MW of wind turbines that are proposed. 

Figure 21 shows the electrical configuration between the HECO interconnection and the 

infrastructure on base at MCBH Kaneohe Bay. 
47

Figure 21: Existing MCBH Kaneohe Bay electrical map

Figure 21 shows the service areas of specific circuits. The feeder capacities in Appendix E show 

that with the proposed wind turbine configuration the wind turbines could tie into circuits 105 

and 104 (both limited to approximately 5 MW), 103 (limited to 3.7 MW), and 12-3, (limited to 

4.9 MW). This total capacity and individual feeder capacity falls short of the proposed wind 

turbine installation capacities, however turbine choice and what exact sites are deemed 

constructible will dictate which circuits may prove economical to interconnect with. 

Recommendations

Create a power flow model for the base to validate any assumptions about integrating PV and 

wind turbines into the existing infrastructure. This should be modeled independently of the 

HECO grid to expose any base induced power flow issues. Also, perform an economic 

evaluation of integrating the PV and turbines with various existing circuits.

Oahu constraints

MCBH Kaneohe Bay lies along a 46 kV line that has the advantage of being closer to the load 

centers along the Southwest coast of the island compared to the existing wind farms on Oahu. 

Existing wind farms on the Northern shores of Oahu require some backup energy storage devices 

to not only smooth the fluctuations of the wind turbine output but also to provide voltage support 

since the turbines are far away from the other generators on the Oahu grid. Some form of voltage 

12M

6MW 9MW
48

support or spinning reserve may be required for this proposed 20-30 MW installation of wind 

turbines and 10 MW of PV at MCBH Kaneohe Bay but this will need to be modeled by HECO. 

HECO has a large model and study for integration of more wind in the GE study.12 The GE 

study found that 100 MW of wind on Oahu would not require any curtailment and thus the

MCBH Kaneohe Bay proposed 20-30 MW wind project may be advantageous for HECO as this 

will increase spatial smoothing. However, the existing 30 MW Kahuku Wind farm combined 

with the proposed 70 MW Kawailoa Wind project will fulfill the study’s100 MW assumption.13

There is also a second phase transmission and wind/solar study including interconnection to 

Maui,14 which discusses mainly the transmission strategies for interconnecting the islands, and

illustrates the planning and modeling that HECO has undertaken.

Close coordination and planning in conjunction with HECO will help identify possible project 

scenarios. These discussions should be started as soon as possible to avoid conflicts later in the 

project. 

Using an electrolyzer to produce hydrogen on base could also assist smoothing the output from 

the wind farm by consuming energy when the grid cannot handle a ramp event at high wind 

speeds. The electolyzer may act as energy storage to increase power if there is a significant fall 

in the output of the turbine generators either due to a fault or sudden drop in wind speed. Sizing 

of this electrolyzer could be optimized for the final wind farm size as well as vehicle fuel 

demand.

 12http://www.hnei.hawaii.edu/PDFs/Oahu_Wind_Integration_Study.pdf 13 http://www.nrel.gov/wind/systemsintegration/pdfs/2011/owits_transmission_interconnection.pdf 14 http://www.nrel.gov/wind/systemsintegration/pdfs/2011/owits_phase2.pdf
49

8 Net Zero Energy Potential

8.1 MCBH Kaneohe Bay Projects

MCBH Kaneohe Bay has implanted some energy efficiency measures with their Energy Savings 

Performance Contract (ESPC) submitted January 2008 by NORESCO. The ESPC covered 

savings in the following categories: lighting, water conservation, occupancy sensors, and HVAC 

controls. NORESCO estimated a total savings of 6,504,301 kWh with the four categories of 

energy conservation measures.

MCBH Kaneohe Bay is planning on installing between 10 and 12 MW of PV with funding from 

power purchase agreements. These projects are in a phased award plan with five task ordering 

agreements listed in Appendix C. To be conservative, projects totaling 10 MW were assumed for 

this analysis. The estimated production from this system is 15,432,643 kWh. The annual savings 

from this system would be about $3,086,528 in year one and increasing in subsequent years as 

the cost of grid electrical energy increases.

8.2 Recommended Additional Energy Projects

Energy Efficiency

NREL estimated the energy efficiency savings potential of the base. Table 26 summarizes the 

potential energy savings at MCBH Kaneohe Bay, which totals 17.03% electrical load reduction, 

6.62% propane load reduction, and 16.5 % overall energy reduction. 

Table 26. Energy Efficiency Savings Potential

Measure Savings (% of fuel type) MMBtu 

Equivalent 

Savings

% Total Site 

Savings

Specific Base Facilities

Commissary (32% reduction) MWh 1,401 2.4% 4,780 2.1%

Barracks (40% reduction) MWh 7,497 12.8% 25,587 11.4%

Offices (43% reduction) MWh 3,215 5.5% 10,972 4.9%

Gym (52% reduction) MWh 467 0.8% 1,593 0.7%

Mess Hall (40% reduction) MWh 1,310 2.2% 4,470 2.0%

Base Wide ECMs

Retro-commissioning MWh 2,023 3.5% 6,904 3.1%

Lighting Occupancy Sensors MWh 935 1.6% 3,190 1.4%

Computer Energy Mgmt MWh 1,387 2.4% 4,732 2.1%

Water Heater Boilers MMBtu 1,251 4.8% 1,251 0.6%

Total

Electricity MWh 18,233 17.03% 62,211 15.9%

Propane MMBtu 1,251 6.62% 1,251 0.6%

Total 

MMBtu

63,462 16.5%

Renewable Energy Analysis

After assessing energy use reduction opportunities at MCBH Kaneohe Bay, NREL evaluated the 

potential for renewable energy generation to meet energy needs that would remain after any 
50

energy efficiency improvements were implemented. The most promising technologies for 

implementation include solar photovoltaics, wind turbines, solar hot water, and daylighting. A 

summary of the technologies and their savings can be seen in Table 27 below.

Table 27. Renewable Energy Technologies: Potential Energy Savings and Payback Period

Project Name Size Savings Source Btu Savings

MMBtu

% of Total 

MMBtu

PV 10 MW 15,432,643 kWh 206,412 14%

Wind Turbines 28.5 MW 92,879,232 kWh 1,242,263 86%

Solar Hot Water 257,509 ft2 11,239 MMBtu 12,925 59%

Daylighting 99,123 ft2 2,092,540 kWh 27,988 2%

Totals 161%

Large wind turbines are the most cost effective form of renewable energy at MCBH Kaneohe 

Bay. Kaneohe Bay should investigate installing large wind turbines near the Ulupau Crater 

which rises ~100‐200 m (~330‐660 ft) above sea level and is ~3‐5 km (~2‐3 mi) away from the 

MCBH Kaneohe Bay airport. There is a training area and landfill nearby. Depending on the land 

area available large turbines should be installed with capacity of around 25- 28.5 MW. This wind 

farm could generate excess energy that could be sold back to the utility or utilized to generate 

hydrogen through MCBH Kaneohe Bay’s electrolysis fuel station being installed for their fleet.

8.3 Net Zero Energy Potential

MCBH Kaneohe Bay can achieve net zero electrical energy through the installation of renewable 

energy technologies and investment in energy efficiency. Net zero energy status can be met with 

a variety of combinations of efficiency, wind turbines, and solar power.

It is not recommended at this time that MCBH Kaneohe Bay pursue thermal renewable energy. 

MCBH Kaneohe Bay’s current thermal energy source is propane. Approximately half of the 

propane usage on base can be replaced with energy efficiency measures and solar hot water 

systems. However it is not recommended at this time that the base abandon all propane use as 

this would require replacing propane powered cooking and hot water systems with either 

hydrogen or electrical systems. Currently a Btu of electrical energy is more expensive than a Btu 

from propane thus this switch would not make financial sense. If MCBH Kaneohe Bay wanted to 

become a full NZEI, it would need to replace its propane powered systems with hydrogen or 

electrical power created by renewable energy. As systems reach the end of their useful life and 

need to be replaced it is recommended that this option be examined. 
51

9 Implementation: Project Planning and Financial Assessment

9.1 Implementation Options

MCBH Kaneohe Bay has a variety of available options for implementing the recommended 

energy projects. The following sections describe these options (note: information on financing 

mechanisms adapted directly from www.femp.energy.gov/financing/mechanisms.html)

Energy Savings Performance Contract (ESPC)

ESPCs enable federal agencies to accomplish energy-savings projects without up-front capital 

costs and without special Congressional appropriations.

An ESPC is a partnership between a federal agency and an energy service company (ESCO). The 

ESCO conducts a comprehensive energy audit for the federal facility and identifies 

improvements to save energy. In consultation with the federal agency, the ESCO designs and 

constructs a project that meets the agency's needs and arranges the necessary financing. The 

ESCO guarantees that the improvements will generate energy cost savings sufficient to pay for 

the project over the term of the contract. After the contract ends, all additional cost savings from 

that time on accrue to the agency. Contract terms up to 25 years are allowed.

The average contract price for a Super ESPC contract undertaken by a federal agency between 

1998 and 2008 was $15.3 million.

15 Typically ESPC contracts need to be at least $1-$2 million

in size to generate interest from the private sector. It should be noted, however, that the life-cycle 

costs of appropriations-funded projects versus ESPC contracts have been shown to be 

approximately the same, if we include all costs and the longer time cycle of appropriations 

funding.

16

Utility Energy Services Contract (UESC)

Another way for federal agencies to implement efficiency and renewable energy projects is 

through utilities. Federal agencies often enter into UESCs to implement energy improvements at 

their facilities. With a UESC, the utility typically arranges financing to cover the capital costs of 

the project. Then the agencies repay the utility over the contract term, drawing on the cost 

savings that the energy efficiency measures generate. Using this arrangement, agencies can 

implement energy improvements with no initial capital investment; the net cost to the federal 

agency is minimal, and the agency saves time and resources by using the one-stop shopping 

provided by the utility.

Power Purchase Agreement (PPA)

PPAs allow federal agencies to finance on-site renewable energy projects while incurring no upfront capital costs.

With a PPA, a developer installs a renewable energy system on agency property under an 

agreement that the agency will purchase the power that the system generates. The agency pays 

 15 DOE Awarded Task Order Report. Federal Energy Management Program. Awarded Energy Service Performance 

Contacts. Accessed 8-24-09. http://www1.eere.energy.gov/femp/pdfs/do_awardedcontracts.pdf 16 Hughes, P.J.; Shonder, J.A.; Sharp, T.; Madgett, M. Evaluation of Federal Energy Savings Performance 

Contracting-Methodology for Comparing Processes and Costs of ESPC and Appropriations Funded Energy Projects. 

ORNL/TM-2002/150. Oak Ridge, Tennessee: Oak Ridge National Laboratory. 2003.
52

for the system through these power payments over the life of the contract. After installation, the 

developer owns, operates, and maintains the system for the life of the contract. MCBH Kaneohe 

Bay has plans to use a PPA to finance the 10 MW solar rooftop and carport projects as is 

outlined in their task ordering plan (Appendix C).

Other Implementation Considerations

Net Metering

Net metering for systems on HECO’s grid is limited to 100 kW. So under the current rules 

MCBH Kaneohe Bay would not be able to build a large enough system to become a net zero 

energy installation. On site storage is an alternative to net metering, but would be prohibitively 

expensive.

Interconnection

Interconnection of renewable energy systems into HECO’s grid is limited by utility rules. The 

rules state that when the aggregate generating capacity per distribution feeder exceeds 10% of 

the peak annual KVA load of the feeder an additional technical study is needed to examine the 

risk of voltage regulation problems and protection malfunction from reverse power flow. 

Analyses such as feeder load flow dynamic stability analysis, transient overvoltage, short circuit, 

and relay coordination may be needed. 

Incentives

Renewable energy projects at MCBH Kaneohe Bay would likely be eligible for a variety of state 

and federal incentives. Energy projects could also be eligible for tax credits if they were owned 

by a third party with tax liability. An overview of the incentives is presented below.

 Federal Investment tax credit or rebate for PV, CSP, wind, and solar hot water systems –

30% credit of the capital cost. 

 The solar hot water systems that displace electrical energy at MCBH Kaneohe Bay would 

be eligible for state incentives. The incentives are $125 per deferred kW, plus $0.05/kWh 

for retrofits and $0.06/kWh for new construction.17

 Hawaii recently passed a feed in tariff program. System sizes up to 5MW are eligible for 

interconnection. Prices and details for the program have yet to be fully developed. 

However the feed in tariff’s program does provide an incentive for renewable energy 

projects and likely simplified interconnection requirements. 18

 Modified Accelerated Depreciation Schedule- A program to reduce tax liability through 

faster than normal depreciation. Approximate schedule is shown below:

 17 DSIRE, http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=HI06F&re=1&ee=1 , accessed 

September, 2010. 

18 DSIRE, http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=HI29F&re=1&ee=1, accessed 

September, 2010. 
53

Table 28. Modified Accelerated Depreciation Schedule

Year 1 2 3 4 5 6

Fraction 0.200 0.320 0.192 0.115 0.115 0.058

NEPA

When planning for and installing the energy projects, MCBH Kaneohe Bay must be aware of 

National Environmental Policy Act considerations. NEPA requires federal agencies to consider 

the environmental impacts of projects. The requirements for NEPA vary based on the specific 

project being undertaken. There are three levels of possible required analysis; categorical 

exclusion, environmental assessment, and an environmental impact statement.19 Building energy 

efficiency upgrades, rooftop energy systems such as PV, daylighting, and solar hot water could 

qualify for categorical exclusion since they are modifications to existing facilities. However 

projects such as ground mount PV or concentrating solar power could require more detailed 

NEPA assessments since they are disturbing land. The environmental assessment would be 

required to determine if these projects would have a significant environmental impact. If it was 

deemed that the projects would have a significant environmental impact a more detailed 

environmental impact study would be required. 

Radar and Wind Turbines

Wind turbines are the recommended renewable energy technology for MCBH Kaneohe Bay. The 

base has an airfield that is used for training operations and there are sometimes compatibility 

issues between wind turbines and radar. Many military and civilian installations have turbines 

located near the airfield and with proper siting of turbines and coordination it is believed that 

these issues can be avoided at MCBH Kaneohe Bay. The military installations listed below have 

successfully resolved this issue:

20

• F.E. Warren Air Force Base, Wyoming – two 660-kW turbines 

(http://www.afcee.brooks.af.mil/ms/msp/center/Vol11No3/10.asp)

• U.S. Navy at Guantanamo Bay, Cuba – four 950-kW turbines

(http://www.defenselink.mil/news/Mar2005/20050329_342.html)

• U.S. Air Force Space Command on Ascension Island – four 225-kW and two 900-kW 

turbines (http://www.inl.gov/powersystems/ascension_island.shtml)

• U.S. Navy at San Clemente Island Base – three 225-kW turbines

(http://www.nelp.navy.mil/pdf_cases/Conservation_Wind_Power_SCI.pdf)

 19 US EPA http://www.epa.gov/Compliance/basics/nepa.html 20 “Wind Turbines and Radar and Informational Resource”, The American Wind Energy Association. 

http://www.awea.org/pubs/factsheets/060602_Wind_Turbines_and%20_Radar_Fact_Sheet.pdf Accessed, 

September, 2010.
54

Implementation Plan

In order for MCBH Kaneohe Bay to achieve net zero energy status and significant reductions in 

source Btu’s, the base needs to implement energy efficiency measures and renewable energy 

systems. MCBH Kaneohe Bay can use ESPC again for energy efficiency measures outlined in 

Section 4. The implementation of renewable energy systems large enough to make the base net 

zero is limited by utility regulations on the maximum size of systems and the cost of energy 

storage systems. Various implementation options are discussed in this section. 

Option#1 Hydrogen Production

Since wind and PV are intermittent generation systems, MCBH Kaneohe Bay would need a way 

to store the energy produced by the systems to balance out demand and generation. These 

systems are discussed in this report and include generation of hydrogen through electrolysis used 

to fuel the new hydrogen fleet and/or possibly a hydrogen fuel cell. The base will soon be able 

to produce hydrogen and in this scenario it would eliminate the need to purchase additional

electricity from HECO to run the electrolysis for this operation. 

Option #2 Enhanced Use Lease

A second option for the base to become a net zero energy installation would be an enhanced use 

lease for a large wind turbine project. Kaneohe has a very high quality wind resource as shown in 

the wind resource assessment done by NREL attached to this report. The base could find a 

developer interested in a large wind farm project on Hawaii. As a consideration for allowing the 

developer to site a wind farm on Kaneohe property the base could receive free electrical energy. 

The Navy has an enhanced use lease program and office setup to support his type of transaction. 

(Additional information on the Navy’s enhanced use lease program can be found here:

http://www.cnic.navy.mil). 

Option #3 Utility Cooperation for Expanded Net Metering or a UESC

A third option for the base to achieve net zero energy status is reach a deal with HECO to allow 

for the interconnection of larger amounts of renewable energy. HECO’s current rules prevent 

MCBH Kaneohe Bay from interconnecting enough renewable energy to achieve net zero status. 

Reaching a deal with HECO where generation is limited to certain conditions like specific ramp 

rates or giving the utility the ability to control and curtail loads would be an effective solution for 

MCBH Kaneohe Bay. MCBH Kaneohe Bay could build renewable energy systems larger than 

their current needs which would allow HECO to receive and sell the additional power, thus 

giving HECO a financial incentive for allowing the interconnection of larger renewables at 

MCBH Kaneohe Bay. A mechanism that could be utilized to facilitate this transaction could be a 

utility energy services contract (UESC). This would allow for the utility to act as a project 

developer for wind energy at MCBH Kaneohe Bay and the base could simply purchase 

renewable power from the utility. Utilizing the utility for this type of arrangement would likely 

make the ability to interconnect a much simpler process. 

Option #4 Feed In Tariff

Hawaii recently passed a feed in tariff program. System sizes up to 5 MW are eligible for 

interconnection. Prices and details for the program have yet to be fully developed. However the 

feed in tariff’s program does provide an incentive for renewable energy projects and likely 

simplified interconnection requirements. MCBH Kaneohe Bay could delay investment until the 

full details of this program are released and develop a project under the feed in tariff.
55

Depending on the technology desired at the base, the optimal implementation option will vary. It 

is recommended that MCBH Kaneohe Bay pursue the lowest net-present cost implementation 

option as well as one that will allow simple interconnection.

9.2 Financial Analysis

This section presents a basic financial analysis of the recommended solution to approaching

NZEI status. This analysis simply provides a sample case and does not necessarily represent the 

actual financial costs of these recommendations. The analysis does not present sufficient detail 

for project implementation but is intended to serve as the basis for further analysis and 

refinement of the energy strategy at MCBH Kaneohe Bay.

For the purposes of financial analysis it was necessary to make numerous assumptions. These 

assumptions include:

• A 20-year project lifetime

• 50% of the solar hot water projects are built in 2011 and the remaining 50% are built in 

2012

• 257,509 ft2 solar hot water systems have a capital costs of $31,536,377

• O&M costs for solar hot water were 0.5% of capital cost escalated at the rate of inflation 

annually 

• 99,123 ft2 of Daylighting has a capital costs of $4,320,360 

• 10 MW of PV are installed at a capital cost of $60,000,000

• PV O&M is $0.006 per kWh or $46,854 per year escalated at the rate of inflation 

annually

• 28.5 MW of wind turbines are installed in 2013 and 2014 at a capital cost of $37,250,000 

• Wind turbine O&M is $3,960,373 per year escalated at the rate of inflation annually

• A discount factor of 3% from National Institute of Standards and Technology 2009 

Energy Price Indices Analysis report was used

• A inflation rate of 1.2% annually from NIST 2009 Energy Price Indices Analysis report 

was used

• Grid electrical energy average price of $0.20 per kWh in 2010

• Propane average price of $2.00 per gallon in 2010

• Propane price escalation rate = 2% annually

• Electrical energy price escalation rate = 2% annually

• Electrical energy load growth rate = 3% annually

• Propane load growth rate = 3% annually 

• It was assumed that the projects were financed with appropriations and were not eligible 

for incentives.
56

Base Case

The energy baseline and cost data obtained for MCBH Kaneohe Bay were used to determine a 

base case for financial comparison. The base case for 2009 is shown in Table 29 below. 

Table 29. Base Case Energy Costs

Base Case 2009

Totals

Grid Electricity (kWh) 107,088,800

Electrical Cost per kWh $ 0.20 

Total Electricity Cost $ 21,417,760

Propane (Gallons) 206,900

Propane Cost (Per Gal) $ 2.00 

Total Propane Cost $ 413,800

Total Cost $ 21,831,560

Using the estimates above and a 20-year lifetime, the approximate cost of the base case scenario 

with no energy efficiency or renewable energy projects was analyzed. The future energy costs 

for any installation are difficult to estimate. For Hawaii, energy costs are particularly difficult to 

estimate because they are largely depended on the price of oil which has been very volatile over 

the last few years. Depending on the future development at MCBH Kaneohe Bay for range 

complexes, new buildings, and troop levels, the electrical load could vary. However, a possible 

scenario is shown in Figure 22 with an energy price increase of 2% annually and a 3% load 

growth rate. For the next 20 years. Under this scenario, energy at Kaneohe will cost $780.8

million, with a net present cost of $543.8 million. 
57

Figure 22. Possible future energy costs

Recommended Scenario

If the recommended renewable energy technologies listed in Table 27 are installed, MCHB

MCBH Kaneohe Bay will likely be able to achieve cost savings. The exact amount of the cost 

savings will be determined by factors such as energy prices, capital costs, implementation 

mechanism, and incentive availability. The most crucial factor for determining the cost savings at 

Kaneohe will likely be a negotiated agreement with HECO to interconnect larger amounts of 

renewables. Without some type of agreement with HECO becoming a net zero energy 

installation will likely not be possible. Several scenarios for cost savings were analyzed.

Net Metering

If MCBH Kaneohe Bay were able to interconnect renewables under an expanded net metering 

arrangement with HECO, the financial scenario would be very attractive. Under this scenario the 

electrical bill of the base would be zero for about half of the project lifetime until the load grows 

enough to surpass the energy generated by the turbines in 2022. This scenario has large capital 

costs for the turbine in 2012 and 2013 and does not assume any incentive eligibility. The total 

cost for this scenario is $393 million with a net present cost of $301.7 million. The annual costs 

are shown in Figure 23.

$- 

$5,000,000 

$10,000,000 

$15,000,000 

$20,000,000 

$25,000,000 

$30,000,000 

$35,000,000 

$40,000,000 

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

Cost ($)

Year

Possible Future Energy Costs

Propane

Electrical
58

Figure 23. Energy costs in net metering renewable energy scenario

Feed in Tariff

Hawaii recently passed legislation to create a feed-in tariff (FIT) policy for renewable energy. 

The details of the program are still being determined regarding interconnection, pricing, and 

technology sizing. The military will be eligible to participate in this program, and MCBH 

Kaneohe Bay could be a great candidate for this program with its wind turbines since they are 

presently most cost effective. Assuming that the base is allowed to connect the turbines under 

this program a cost savings to the base would be likely. The amount of savings would be less 

than under net metering but still significant. The FIT rate for wind on Oahu has not been set yet. 

For this analysis, we estimated it to be $0.161 per kWh, and we assumed this rate did not 

increase over the 20-year project lifetime.21 Under this scenario, the wind energy generated by 

the turbines at MCBH Kaneohe Bay would be bought by the utility company at the FIT price of 

$0.161/kWh. MCBH Kaneohe Bay would still be purchasing power at the HECO rate, thus the 

annual savings to MCBH Kaneohe Bay are the difference between the revenue generated by 

selling wind power to HECO and the cost of buying power. These savings are approximately 

$12.6 million per year. The total cost for this scenario is $632.5 million with a net present cost of 

$471.7 million. The annual costs are shown in Figure 24. 

 21John Cole, National Association of Regulatory Utility Commissioners Meeting, July 2010. 

http://www.narucmeetings.org/Presentations/John%20Cole_NARUC.Hawaii%20FIT.pdf

$- 

$10,000,000 

$20,000,000 

$30,000,000 

$40,000,000 

$50,000,000 

$60,000,000 

$70,000,000 

201020112012201320142015201620172018201920202021202220232024202520262027202820292030

Annual Energy Cost

Year

Energy Costs in RE Scenario
59

Figure 24. Energy costs in feed in tariff renewable energy scenario

Enhanced Use Lease 

This scenario requires the base to find a developer interested in a large wind farm project on 

MCBH Kaneohe Bay land that would sell energy to the utility. As a consideration for allowing 

the developer to site a wind farm on MCBH Kaneohe Bay property, the base could receive free 

electrical energy. Since MCBH Kaneohe Bay has a very good renewable energy resource, but 

land is restricted, this scenario is not likely possible. The scenario where this might be possible is 

if MCBH Kaneohe Bay were to host the substation for the submarine cable from the big wind 

project on Lanai. The substation is estimated to require five acres of land to convert the DC 

transmitted power to AC power for use on the island. Presently, the submarine cable will be 

routed through MCBH Kaneohe Bay to the HECO substation near the base. MCBH Kaneohe 

Bay could become an NZEI by purchasing a portion of the transmitted energy from the Big Wind 

project on Lanai. This would require the base give to up some of its land and it is unclear if the 

base is able to do so with its mission requirements. 

- 

10,000,000 

20,000,000 

30,000,000 

40,000,000 

50,000,000 

60,000,000 

70,000,000 

80,000,000 

Annual Energy Cost

Year

Energy Costs in RE Scenario
60

10 Conclusion

NREL’s net zero analysis evaluated opportunities for energy efficiency, renewable energy, and 

transportation fuel reduction at MCBH Kaneohe Bay. The analysis shows that MCBH Kaneohe 

Bay has the potential to make significant progress toward becoming a net zero installation. If the

base implements the recommended energy projects and savings measures, it would achieve a 

96% site energy reduction and a 99% source energy reduction. By achieving this status, the base 

will set an example for other military installations, provide environmental benefits, reduce costs, 

increase energy security, and exceed its goals and mandates. 
61

Appendix A. Renewable Energy Resource & Environmental Maps

Figure 25. Wind resource on Oahu
62

Figure 26. Solar resource on Oahu 

(Note: MCBH Kaneohe Bay is in the solar grid with average 5.50-5.75 kWh/m2

/Day)
63

Figure 27. Concentrated solar power resource map for Oahu

(Note: MCBH Kaneohe Bay’s average solar resource is 4.747 kWh/m2

/Day)
64

Figure 28. Flood zones

Source: MCBH Kaneohe Bay Master Plan 2006
65

Figure 29. Biological sensitive lands

Source: MCBH Kaneohe Bay Master Plan 2006
66

Figure 30. Geothermal resource on Oahu 

(Note: MCBH Kaneohe Bay is very low geothermal resource)
67

Figure 31: Biomass resource maps for all Hawaii islands

(Note: Oahu has 50-100 Thousand Tonnes/year of Biomass)
68

Appendix B. Specific Energy Efficiency measures 

Specific Main Base Facilities

Offices

There is over 391,816 ft2 of office space on the base at MCBH Kaneohe Bay. The average 

building size is 10,590 ft2. Offices comprise 11.5% of the total installation building square 

footage. The office spaces consume an estimated 7,512 MWh of electrical energy each year. The 

offices consume a very small amount of propane, which is used for domestic water heating. An 

energy model of the average office building was built22 to estimate the energy reduction potential 

of the offices at MCBH Kaneohe Bay. The average energy use intensity (EUI) for the office 

spaces at MCBH Kaneohe Bay is 67.3 MMBtu/1000 ft2

/Yr. The HECO benchmark for office 

buildings in Hawaii is 77.9 MMBtu/1000 ft2/Yr. Although the offices are operating below the 

HECO benchmark, there is still a significant amount of savings that could be realized through 

energy efficiency measures. 

Figure 32. Modeled electricity end use office buildings

The NREL team spoke with the onsite staff about the base buildings, and visited several of the 

buildings while on site. Several opportunities for savings were identified based on discussions 

about the base-wide mechanical systems. The team built a basic energy model using typical 

office building assumptions and bundled the following ECMs to estimate the energy that could 

be saved in the offices. 

 22 The energy modeling program eQUEST was used to build the energy model. 
69

Energy model ECMs included:

• Implement a night time and weekend setback on the HVAC system 

• Close the outside air dampers during unoccupied hours

• Replace air cooled chillers with a variable speed water cooled chillers 

• Convert CV air delivery systems to a VAV system

• Put a VFD on the cooling tower fan

• Implement a condenser water temperature reset

• Chiller water temperature reset

• Put a VFD on the chilled water pumps.

The energy reduction potential was calculated to be 43% for the average size office building. 

Expanding this reduction potential to all of the office space at MCBH Kaneohe Bay equates to 

3,215 MWh/yr. 

Typical office ECMs that could potentially be implemented, but were not investigated by the 

NREL team include: 

• Lighting level reduction, and use of LED task lighting 

• Replace all existing faucets and toilets with low flow devices

• Put all offices on the central DDC system.

Commissary

The commissary is an on-base commercial facility that provides goods and services to military 

personnel and their families. The commissary is 89,625 ft2, which comprises 2.6% of the total 

installation building square footage. The commissary consumes an estimated 4,427 MWh per 

year of electrical energy. The commissary does not consume any propane. The commissary 

represents 7.6% of total base electrical energy consumption. The energy use breakdown of the 

commissary is shown below. The EUI for the commissary at MCBH Kaneohe Bay is 168.5 

MMBtu/1000 ft2

/Yr. The HECO benchmark for grocery stores in Hawaii is 181.0 MMBtu/1000 

ft2/Yr. Although the commissary is operating below the HECO benchmark, there is still a 

significant amount of savings that could be realized through energy efficiency measures. 
70

Figure 33. Modeled electricity end use in the commissary

The NREL team spoke with the onsite staff about the base buildings and examined the 

mechanical systems while on base. The team built a basic energy model using typical food sales 

assumptions and bundled the following ECMs to estimate the energy that could be saved at the 

commissary. 

Energy model ECMs include:

• Implement a night time setback on the HVAC system

• Close the outside air dampers during unoccupied hours

• Convert the system from a CV system to a VAV system. 

• Replace the current chiller with a high efficiency water cooled variable speed chiller 

• Put a VFD on the cooling tower fan

• Implement a condenser water temperature reset

• Chiller water temperature reset

• Put a VFD on the chilled water pumps.

With these measures bundled, the commissary has the potential to save 1,401 MWh which 

represents a 32% reduction in the electrical load of the commissary. 

Typical food-sales ECMs that could potentially be implemented, but were not investigated by the 

NREL team include: 

• Lighting level reduction
71

• Switching the light bulbs in freezers and refrigerators to LED bulbs to save on both 

cooling and lighting energy. Incandescent bulbs give off significant amounts of heat and 

increase the refrigeration energy requirements. The heat produced by standard bulbs 

increases energy requirements for the freezers 25%-50%.23

• Utilize waste heat from refrigeration to reduce the domestic hot water load of the building

• Implement static pressure reset.

Barracks

The barracks of the base at MCBH Kaneohe Bay provide housing for service members on the 

base. There are over 1,155,386 ft2 of barracks and similar housing on the base at MCBH 

Kaneohe Bay. The average building size is 30,405 ft2

. Barracks and similar housing comprise 

32% of the total installation building square footage. The barracks consume an estimated 18,668 

MWh per year of electrical energy, and an estimated 4,696 MMBtu of propane. The barracks use 

propane to heat water. The EUI for the barracks at MCBH Kaneohe Bay is 61.9 MMBtu/1000 

ft2/Yr. The HECO benchmark for lodging in Hawaii is 55.1 MMBtu/1000 ft2/Yr. The barracks at 

MCBH Kaneohe Bay are slightly higher than the HECO benchmark. This combined with the

measures that were identified during the site visit indicate that there are improvements that can 

be made in energy efficiency. 

Figure 34. Modeled electricity end use in barracks

The NREL team spoke with the onsite staff about the barracks and looked at the mechanical 

systems for some of them. Several opportunities for savings were identified based on discussions 

about the base wide mechanical systems. The team built a basic energy model using typical 

 23 “Lighting The Way to Greener Retail”, Nualight. http://www.nualight.ie/lighting_the_way_to_greener_retail.pdf
72

barracks assumptions and bundled the following ECMs to estimate the energy that could be 

saved in the barracks. 

Energy model ECMs include:

• Replace the air cooled chiller with an HE water cooled chiller

• Convert the CV air delivery system to VAV

• Implement a variable flow chilled water system

• Replace pump and fan motors with premium efficiency motors 

• Replace all fan belts with cogged v-belts.

The energy reduction potential was calculated to be 40% for the average size barrack. 

Expanding this reduction potential to all of the barracks at MCBH Kaneohe Bay equates to 7,497

MWh/yr. 

Typical housing ECMs that could potentially be implemented, but were not investigated by the 

NREL team include: 

• Replace washer and dryer with energy star appliances

• Install low flow faucets, showerheads, and toilets

• Install occupancy monitoring devices such as card readers to ensure that non-occupied 

units are not being heated or cooled.

Main Gym

The main gym on base provides a work out facility for military personnel and their families. The 

gym consists of gymnasium space, weight rooms, aerobics rooms, and other spaces for exercise. 

The main gym comprises 0.6% of the total installation building square footage. The gym 

consumes an estimated 899 MWh per year of electrical energy, and 1.020 MMBtu per year of 

propane. The main gym uses propane for domestic hot water. The facility also utilizes some 

waste heat from the chillers to heat domestic hot water. The gym represents 1.5 % of total base 

electrical energy consumption. The energy use breakdown of the gym is shown below. 
73

Figure 35. Modeled electricity end use in main gym

The NREL team spoke with the onsite staff about the gym and looked at the mechanical systems. 

Several opportunities for savings were identified based on discussions about the base wide 

mechanical systems. The team built a basic energy model using typical gym assumptions and 

bundled the following ECMs to estimate the energy that could be saved. 

Energy Model ECMs include:

• Implement an unoccupied setback on the HVAC system

• Close the outside air dampers during unoccupied hours

• Replace the air cooled chiller with a HE water cooled chiller

• Convert the CV air delivery system to VAV

• Implement a variable flow chilled water system.

With these measures bundled, the main gym has the potential to save 467 MWh which represents 

a 52% reduction in the building’s electrical load. 

Typical gym ECMs that could potentially be implemented, but were not investigated by the 

NREL team include: 

• Lighting level reduction

• High bay lighting improvements

• Lighting controls for nighttime and weekend setbacks
74

• Occupancy sensors in the restrooms

• Low flow faucets and toilets

• Low flow showers.

Food Services 

The food services on base provide dining facilities for all military and civilian personal and on 

the base. There are several facilities consisting of everything from fast food chains to mess halls. 

The food services comprise 2.9% of the total installation building square footage. The food 

services consume an estimated 3,266 MWh per year of electrical energy, and over 4,526 MMBtu

per year of propane. The main gym uses propane for domestic hot water and cooking. The food 

services represent 5.6% of total base electrical energy consumption. The energy use breakdown 

of the food services is shown below. The EUI for the Food Services at MCBH Kaneohe Bay is 

176.5 MMBtu/1000 ft2/Yr. The HECO benchmark for restaurants in Hawaii is 180.4 

MMBtu/1000 ft2/Yr. Although the food services are operating below the HECO benchmark, 

there is still a significant amount of savings that could be realized through energy efficiency 

measures. 

Figure 36. Modeled Electricity End Use Food Services

The NREL team spoke with the onsite staff about the food services and looked at the mechanical 

systems. Several opportunities for savings were identified based on these discussions and the site 

visit. The team built a basic energy model using typical food service assumptions and bundled 

the following ECMs to estimate the energy that could be saved. 
75

Energy model ECMs include:

• Implement an unoccupied setback on the HVAC system

• Configure the kitchen exhaust fans to operate on demand 

• Replace the air cooled chiller with a HE water cooled chiller

• Convert the CV air delivery system to VAV

• Implement a variable flow chilled water system.

With these measures bundled, the main gym has the potential to save 1,310 MWh which 

represents a 40% reduction in the building’s electrical load. 

Typical Food Service ECMs that could potentially be implemented, but were not investigated by 

the NREL team include: 

• Heat recovery from the chillers to heat domestic hot water

• Low flow faucets and toilets.
76

Appendix C. Solar PV Projects Identified by MCBH Kaneohe Bay 

The following tables were received from MCBH Kaneohe Bay during the site visit and map out 

each potential site for PV on carports and rooftops. PV Watts Version 1 was used to calculate the 

annual output of energy for a given carport area. Table 30 lists the potential carports for PV 

installation. There are 24 carport sites selected that could generate ~2.70 MW of DC peak power. 

Table 31 lists all the potential rooftop area available for PV. The condition of the roof and 

number of existing skylights is noted in the table. The total area available for PV is 745,066 ft2

and could produce ~7.45 MW of peak power.

Table 32 outlines the proposed sites in each task order for the phase award plan provided by 

MCBH Kaneohe Bay. 
77

Table 30. Carport PV Sites for MCBH Kaneohe Bay

MCBH Solar PV 

Carports

Revised: 5 June 2009

Scope: Based on carport structure and amorphous silicon photovoltaic roofing. Work includes installation of power inverter and all electrical connections, 

including electric grid connection, and small building to house inverters at each of 24 locations.

Bldg - Parking Lot

Parking 

Stalls Watts/Stall

Peak 

Capacity 

KW (dc)

(1) 

Annual 

Output kWh Remarks

+++ Kaneohe Bay +++

1604/1632 82 900 74 102,125

Two row carport to cover parking spaces in the center of the parking 

lot with head-to-head parking from each side (37).

1634/1635 60 900 54 74,523

Two row carport to cover parking spaces in the center of the parking 

lot with head-to-head parking from each side (27).

1655/1656 156 900 140 193,209

Three separate carport structures will cover parking spaces in the 

center of the parking lot with head-to-head parking from each side 

(24,24,22).

6109/6477/6088 546 900 491 667,612

One single row carport structure (40), three double row (30), three 

double row (26), six double row (27,25,23,15,12,9)

1090 248 900 223 307,754 One double row carport structure (49), three single row (51,51,48)

CSSG-3 Motor Pool, 3017 168 900 151 208,390

Six single row carport structures (20) for tactical vehicles, and one 

double row (8), three single row (13,13,6) for POVs

3037 104 900 94 129,726 Two double row carport structures (22,30)

5070/5071 54 900 49 67,623 One double row carport structure (27)

221-229, 4009 281 900 253 349,156

Two double row carport structures (34), four single row carport 

structures (30,36,34,45)

219 142 900 128 176,648

Two double row carport structures (23), three single row carport 

structures (15,15,20)

242 74 900 67 92,464

Carport to cover parking spaces in the center of the parking lot with 

head-to-head parking from each side (19). Carport along each edge 

for head-in parking (24 + 12)

Facilities Motor Pool, 352 72 900 65 89,704

Four single row carport structures (18), high bay to accommodate 

trucks and buses

3rd Rad Batt Motor Pool, 

373 75 900 68 93,844 Three single row carport structures (25) for tactical vehicles

Deployed Veh Parking, 370 700 900 630 869,441 Five double row carport structures (70) for deployed vehicle parking

503 80 900 72 99,365 Two single row carport structures (40)

502 61 900 55 75,904 Three single row carport structures (8, 18, 35)

3088 119 900 107 147,667

Two double row carport structures (15, 24) and two single row carport 

structures (15, 26)

SUBTOTALS 3,022 2,720 3,745,155

Assumptions: 1) PV Watts, Ver 1, used to calculate annual output Total Rounded

2) Current electric rate is $0.20/kWh

3) Installation cost is $11/watt (based on Solar Integrated Inc.quote + $5,000 for a Monitoring System Radio Link)
78

Table 31. Rooftop PV sites for MCBH Kaneohe Bay

Location is MCBH Kaneohe Bay, unless noted 

otherwise South

Rev: 6/5/2009 6/5/2009

LOC+ 

MAP 

GRID

FAC

NO

YEAR

BUILT

# 

FLRS

BLDG NAME 

DESIGN DESC

TOTAL 

BLDG 

AREA

APPROX 

AREA FOR PV 

LONG AXIS 

ORIENTATION

ROOF 

SUPPORT 

CONDITION, 

REROOF, 

OR REPAIR 

NOTES

H18 101 1941 2 Aircraft Maint 

Hangar

110,085 93,000 

NNE -SSW

Steel 

Truss

99%, 

Reroofed 

1988

28 Plastic 

Dome 

Skylights

H18 102 1941 2 Aircraft Maint 

Hangar

106,620 93,000 NNE -SSW Steel 

Truss

74%, 

Reroofed 

1988

32 Plastic 

Dome

Skylights

H17 208 1941 1 Warehouse 27,450 31,000 NNE -SSW 99%, 

Reroofed 

2001

H17 209 1941 1 Warehouse 55,840 54,000 

NNE-SSW

81%, Roof 

Repairs 

2007

5 Roofs, 

HI0403M 

compl 

8/2007

H17 242 1941 1 Admin/Warehouse 20,710 24,866 

NNE -SSW

Wood 81%, 

Reroofed 

2006
79

Location is MCBH Kaneohe Bay, unless noted 

otherwise South

Rev: 6/5/2009 6/5/2009

LOC+ 

MAP 

GRID

FAC

NO

YEAR

BUILT

# 

FLRS

BLDG NAME 

DESIGN DESC

TOTAL 

BLDG 

AREA

APPROX 

AREA FOR PV 

LONG AXIS 

ORIENTATION

ROOF 

SUPPORT 

CONDITION, 

REROOF, 

OR REPAIR 

NOTES

K16 250 1943 1 Warehouse 47,460 52,700 

NNE -SSW

100%, 

Reroofed 

2005

5 Roofs, 

HI0106M 

compl 

11/2007

J16 271 1944 1 Warehouse 15,360 16,000 

WNW-ESE

HI0208Mcompleted 

9/2005

K18 373 1943 2 Vehicle Maint 

Shop

57,775 22,500 

WNW-ESE

Rigid 

Steel 

Frame & 

Purlins

88%, Reroofed 

2003

32 FRP 

skylight 

panels 

excludes 

whse 

portion

J18 375 1944 2 Aircraft Maint 

Hangar

62,740 32,700 Various Steel Truss MCD- in 

progress

2 Roofs

G12 1090 1953 1 Exchange Retail 72,650 35,000 Various Concrete 60%, 

Reroofed 

1988

North, 

East, and 

West 

Roofs
80

Location is MCBH Kaneohe Bay, unless noted 

otherwise South

Rev: 6/5/2009 6/5/2009

LOC+ 

MAP 

GRID

FAC

NO

YEAR

BUILT

# 

FLRS

BLDG NAME 

DESIGN DESC

TOTAL 

BLDG 

AREA

APPROX 

AREA FOR PV 

LONG AXIS 

ORIENTATION

ROOF 

SUPPORT 

CONDITION, 

REROOF, 

OR REPAIR 

NOTES

G13 1092 1953 1 Warehouse 20,100 22,000 

NW-SE

Concrete 41%, 

Reroofed 

2002

Existing 

roofing 

damage 

not yet 

repaired as 

of 2/21/08

96.G12 1404 1973 2 MX Warehouse 37,158 27,600 

NNE -SSW

Rigid Steel 

Frame & 

Purlins

38%, 

HI0502MRoofing 

Replacement 

in progress 

G14 1629 1974 1 Enlisted Club 32,256 25,500 

WNW-ESE

Rigid Steel 

Frame & 

Purlins

40%, Original 

Roof 1974

H14 1666 1976 1 Bowling Alley 17,040 17,300 

NNW-SSE

? 45%, 

Reroofed 

2000

J13 3037 1983 1 Gymnasium 32,800 30,000 Various Rigid Steel 

Frame & 

Purlins

81%, New 

Addition Roof 

1998

3 Roofs, 22 

FRP 

Skylight 

Panels
81

Location is MCBH Kaneohe Bay, unless noted 

otherwise South

Rev: 6/5/2009 6/5/2009

LOC+ 

MAP 

GRID

FAC

NO

YEAR

BUILT

# 

FLRS

BLDG NAME 

DESIGN DESC

TOTAL 

BLDG 

AREA

APPROX 

AREA FOR PV 

LONG AXIS 

ORIENTATION

ROOF 

SUPPORT 

CONDITION, 

REROOF, 

OR REPAIR 

NOTES

L16 4005 1987 1 Warehouse 27,904 33,800 

NW-SE

HI0309Mcompleted 

8/2006

L17 4075 1987 1 Warehouse 18,880 22,500 

NW-SE

G11 4088 1987 1 Med Warehouse 37,589 33,600 

NNE -SSW

Rigid 

Steel 

Frame & 

Purlins

94%, Roof 

Repair 2008

22 FRP 

Skylight 

Panels, 

HI0308Min 

progress 

J11 6109 

& 

6477

1996 

& 

1998

1 Exchange Retail 103,207 78,000 

N-S

97%, 

Original 

Roofs

incl Svc 

Outlet 

Bldg 6477

TOTAL PV 

ROOF AREA

745,066 ft2 7,451 kW 

peak
82

Table 32. MCBH Kaneohe Bay PV Projects Phased Award Plan
83

Appendix D: Wind Resource & Turbine Placement

The data was collected from an anemometer towers installed at 50 meters, Latitude: 210 26’ 

32.5” N and Longitude: 1570 44’ 16.7”W, elevation 4 meters. Prevailing wind direction is 60-

750.Average annual wind speeds from collected data at two different heights is:

• 80m – 7.08m/s

• 100m-7.21m/s

The average air density for the monitoring period was 1.185 kg/m3

. This site is characterized by 

very low shear, with a power law exponent of approximately 0.070, and low turbulence. 

Turbulence intensity (TI) is essentially a measure of the ‘gustiness’ of the wind, and is defined as 

the standard deviation of the wind speed divided by the average wind speed for a given 

measurement period (typically 10 minutes). Simply put, the turbulence intensity measured at this 

site is relatively low, which allows the use of IEC class IIIA turbines. The Mean TI was 

measured at 0.078 and representative TI being 0.107, both these are from the IEC 3rd revision 

from 2005 standard. 

Figure 37. Anemometer placement at N.E tip of MCBH Kaneohe Bay

Training Area 

near crater

Landfill

Met Tower
84

Figure 38. Monthly wind speed profile at MCBH Kaneohe Bay

Figure 39. Diurnal wind speed profile

The wind data month of April for 2010 was lost and this plot in Figure 38 does not represent the 

true monthly variation that will be seen on site. The HOMER model wind resource file was 

synthesized by using data from May to replace the missing data. 
85

The following figures show wind turbines placed within MCBH Kaneohe Bay on potential sites 

with good wind resource. The spacing between the turbines assumes 2-3 rotor diameters. The 

spacing also considers proximity to housing for noise and flicker reasons. 

Figure 40. Potential sites for wind turbines
86

Figure 41. Potential wind turbine placement

Figure 42. Potential wind turbine placement
87

Figure 43. Potential wind turbine placement
88

Appendix E: Distribution Feeder Capacity and Load

Figure 44. Distribution feeder capacities and load

Source: MCBH Kaneohe Bay Electrical Study