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Contract No. DE-AC36-08GO28308

Summary Report of the INLJISEA Workshop on Nuclear 

Hybrid Energy Systems

Mark Antkowiak and Mark Ruth

National Renewable Energy Laboratory

Richard Boardman, Shannon Bragg-Sitton, 

Robert Cherry, and Lee Shunn

Idaho National Laboratory

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Summary Report of the INLJISEA Workshop on Nuclear 

Hybrid Energy Systems

Mark Antkowiak and Mark Ruth

National Renewable Energy Laboratory

Richard Boardman, Shannon Bragg-Sitton, 

Robert Cherry, and Lee Shunn

Idaho National Laboratory

Prepared under Task No. 6A50.1027

Technical Report

NREL/TP-6A50-55650

July 2012
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Acknowledgments

This report summarizes a workshop jointly sponsored by the Joint Institute for Strategic Energy 

Analysis (JISEA) and the Idaho National Laboratory (INL). The authors would like to thank all 

the participants for their presentations and insights during the workshop. This workshop report is 

also being published as an INL report with the following INL report number: INL/EXT-12-

26551. 
iv

Abstract

Hybrid energy systems utilize two or more energy resources as inputs to two or more physically 

coupled subsystems to produce one or more energy commodities as outputs. Nuclear hybrid 

energy systems can be used to provide load-following electrical power to match diurnal to 

seasonal-scale changes in power demand or to compensate for the variability of renewable wind 

or solar generation. To maintain economical, full rate operation of the nuclear reactor, its thermal 

energy available when power demand is low could be diverted into making synthetic vehicle 

fuels of various types. The Institute for Nuclear Energy Science and Technology (INEST)1 and 

the Joint Institute for Strategic Energy Analysis (JISEA)2

co-sponsored an international 

workshop to identify research topics important in advancing the potential use of hybrid systems

with a specific focus on nuclear-renewable hybrid systems. The workshop included presentations 

ranging from energy challenges and research and development (R&D) directions being pursued 

by nations to multiple options for hybrid systems. Those options include one that is being 

commercialized to other opportunities and analysis results quantifying them. The workshop also 

involved two breakout sessions—one focused on thermal energy management issues especially 

at unit-operation scale and the second focused on system operations issues including system 

controls, regulatory issues, technical and economic analysis, and market challenges. A discussion 

involving the full group focused on more general issues such as societal involvement and 

participation. Key criteria for selecting hybrid energy system projects and metrics for comparing 

them were also identified by the full group. The workshop’s findings are being used initially by 

INEST to define topics for a research preproposal solicitation. 

 1 INEST is a joint alliance between the Idaho National Laboratory and five partner universities: the Massachusetts 

Institute of Technology, North Carolina State University, The University Of New Mexico, Oregon State University, 

and the Ohio State University.

2 JISEA is operated by the Alliance for Sustainable Energy, LLC, on behalf of the National Renewable Energy 

Laboratory, the University of Colorado-Boulder, the Colorado School of Mines, Colorado State University, the 

Massachusetts Institute of Technology, and Stanford University.
1

1 Introduction and History

Hybrid energy systems utilize two or more energy resources as inputs to two or more physically 

coupled subsystems to produce one or more energy commodities as outputs. These energy 

conversion subsystems take an energy form, typically a primary resource such as wind’s kinetic 

energy or the chemical energy in coal, and process it into a more generally useful energy product 

such as electricity or vehicle fuel, which can then be used to provide energy services such as 

cooling or transportation. The benefits generated by hybrid operation can include higher overall 

energy usage efficiency, better utilization of capital equipment, reduced emissions [especially of 

carbon dioxide (CO2)], and use of domestic resources rather than imported petroleum to make

vehicle fuel. 

Hybrids can be steady-state systems; for example, using hydrogen generated by nuclear-powered 

electrolysis to provide additional chemical energy to a coal-to-liquids process, thereby reducing

overall CO2 emissions. Hybrid systems can also operate transiently; for example, using a nuclear 

power plant to make electricity during the day but diverting its thermal generation capacity 

unneeded at night to a synthetic fuels process such as natural gas conversion to synthetic 

gasoline. Energy storage systems can be incorporated into transient hybrid energy systems to 

improve their ability to respond to dynamic energy supply or demand changes and into steadystate systems to allow for production variations with constant demand. 

Idaho National Laboratory (INL) has conceived and analyzed hybrid energy systems for several 

years, primarily under Laboratory Directed Research and Development funding and with a focus 

on using a nuclear reactor as an energy source. Recent work has concentrated on systems that 

can provide load-following electrical power, allowing nuclear systems to meet electrical demand 

above base-load levels. The ability to follow normal diurnal transients of hours duration also 

allows these systems to provide substantial, if not complete, compensation of variations in the 

output of wind or solar generation facilities. In this way, both nuclear and variable renewable 

sources of low CO2 power can increase their contribution to meeting national power demand. 

In recognition of this synergy, in September 2011, a workshop to explore cooperative nuclearrenewable power generation was organized by the Joint Institute for Strategic Energy Analysis

(JISEA) with INL, among numerous others, attending. JISEA is a cooperative venture of the 

National Renewable Energy Laboratory (NREL), the University of Colorado-Boulder, the 

Colorado School of Mines, Colorado State University, the Massachusetts Institute of Technology

(MIT), and Stanford University that provides in-depth analysis of energy policy options. NREL 

itself has a long history of work in developing and evaluating renewable energy systems of many 

types. The consensus of that meeting was that there were significant opportunities for the two 

technologies to support each other. 

Also during mid-2011, INL began organizing a new Center of Research and Education (CORE) 

within its Institute for Nuclear Energy Science and Technology (INEST). INEST supports 

academic research done collaboratively with an INL researcher in defined areas of nuclear 

engineering, with this CORE, the fifth one established, being focused on nuclear hybrid energy 

systems. As part of establishing this CORE, an international workshop to identify appropriate 

research directions was planned for spring 2012. Because this workshop was recognized as a 

natural continuation of the discussions started at the JISEA meeting, INL and JISEA jointly 

planned it. 
2

This report documents the results of that workshop, which was held on April 3–4, 2012, in Salt 

Lake City, Utah. About 40 people representing national laboratories, universities, and energy 

companies attended from across the United States and from China and France. The agenda and 

list of attendees are included as Appendices A and B. 
3

2 Overview Presentations

The program began with several presentations providing an overview of already established 

activities similar to or supportive of hybrid energy systems. The full presentations are available 

at https://inlportal.inl.gov/portal/server.pt?tbb=hybrid. Key points from them and the associated 

discussions are summarized here. 

2.1 Grand Energy Challenges

Doug Arent of JISEA discussed the Grand Energy Challenge, observing that market, regulatory, 

and political challenges are greater than technical ones. Technology and informatics are 

changing the ways energy is used. The enhanced information exchange and expectation for 

transparency via social networks could potentially have huge effects on energy, particularly the 

social acceptance of energy sources, transmission and other infrastructure, and utilization. 

Getting leaders to address grand challenges requires that they hear from many trusted 

messengers. Thus, the availability of credible, objective data, information, and tools is critical to 

inform energy decisions at local, regional, national, and global levels. International partnerships 

bring considerable value because technology supply chains are global and precompetitive 

research and development (R&D) can benefit all parties. There are many drivers to energy 

change, including energy security, environmental impacts, and economics, and the relative 

importance among these factors is location and context dependent. In many examples, local 

issues such as air quality, water availability and quality, and local economic situation may be 

“closer to the political bulls-eye” than the global environment. 

2.2 A Wyoming Case Study

The State of Wyoming was presented as a case study in energy development by Bob Ballard of 

the University of Wyoming, who was also representing the State of Wyoming and the Wyoming 

Business Council. Wyoming is the top state for total energy production (largely from coal) and is 

now tenth in the country in megawatts of wind capacity. This number has been increasing 

although they are constrained by transmission capacity. They are interested in combining 

renewable generation with other systems to be able to provide energy reliably to large industrial 

users. Since 2004, the university has committed $228.6 million to energy research from various 

sources. The school has three focus areas: 

• Unconventional reservoirs (tight gas, shale gas, oil shale, and residual oil zones) 

• Climbing the value chain (adding value to existing resources and creating products 

and markets)

• Wind and solar energy (efficiency improvement, intermittency mitigation, and energy 

storage).

2.3 Overview of Hybrid Systems in China

An overview of energy research in China was given by Zhiyuan Zhu of the Chinese Academy of 

Sciences (CAS) Shanghai Branch. CAS has a broad program investigating renewable, fossil, and 

nuclear energy. Because the country has large reserves of coal, there is a major effort on coal-tochemicals conversion, as well as coal-to-liquid fuels. Recently the CAS has begun doing nuclear 

power research after five decades of not working in that area. Their nuclear focus is on thoriumfueled molten salt reactors (TMSR) (motivated by China’s thorium reserves) and on accelerator 

driven systems. There is interest in producing hydrogen with a TMSR or with concentrating solar 
4

power (CSP), especially through the use of high temperature electrolysis. Their development 

timeline includes demonstration of 2, 10, and 100 MWe TMSRs in the years 2015, 2020, and 

2030, respectively. Hydrogen production ties to their interests in coal conversion and possible 

recycling of CO2 as a carbon source for chemical syntheses. In response to questions, Zhu noted 

that reducing water usage for either cooling or processing has not been an objective and that 

industrial participation in chemical process development becomes necessary at the demonstration 

scale because CAS cannot afford to do those projects by itself. 

2.4 An Industrial Perspective on Hybrid Energy

An industrial perspective on hybrid systems was presented by Max Peter of GE Global Research. 

GE has recently introduced a commercial hybrid system consisting of a natural gas combined 

cycle power plant with additional heat input from CSP. Their observations about such systems 

include that plant outputs should be controllable, hybrids must demonstrate that they do not 

disrupt operations or revenue of the component systems, performance guarantees are challenging 

for hybrids, and having a single system integrator as a turnkey provider may be necessary to 

overcome technological stovepipes until these systems are more mature and proven. 

2.5 Summary of 2011 Nuclear-Renewable Synergies Workshop

Mark Ruth of NREL provided a summary of the fall 2011 JISEA workshop on synergies 

between nuclear and renewable energy. The workshop’s objective was to assemble experts to 

identify and prioritize potential synergies between nuclear and renewable energy and to identify 

potential leveraging opportunities. Opportunities were identified and prioritized. Breakout 

discussion groups were organized for each of the three high priority topics: hybrid energy 

systems, value proposition/business case, and energy for transportation. Each group identified 

the potential, challenges, priority analysis needs, and priority R&D opportunities in their area. 

The workshop report is published at www.nrel.gov/docs/fy12osti/52256.pdf. The workshop was 

considered valuable because it assembled members from various technology and policy 

communities and provided impetus for collaboration. Integrating ideas across these disciplines is 

key to building support for the idea of hybrid energy systems. One of the purposes of the Salt 

Lake City workshop was to integrate a range of ideas for hybrid energy systems and determine 

R&D needs. 

2.6 Nuclear-Renewable Hybrid Systems with Thermal Energy Storage

Paul Denholm of NREL discussed the role of thermal energy storage in nuclear-renewable 

hybrid systems. Over 60% of electrical demand can be met by base-load or nearly base-load 

systems (those with over 96% capacity utilization), a regime well suited to nuclear plants. 

However, the remaining 40% requires systems that can be operated economically on a part-time 

basis. Adding variable renewable generation to the mix increases the need for flexible, part-time 

generation. Even if a nuclear plant is agile enough to follow and counterbalance the variability of 

wind, operating at less than full rates is not economically attractive. Adding thermal storage to a 

system addresses both of these issues. However, NREL has not done an economic analysis of the 

cost of thermal storage. 

2.7 Nuclear Reactor Technologies for Hybrid Applications

Michel LeComte, recently retired from AREVA, provided a French perspective. France has no 

coal, oil, or gas of its own so it depends on nuclear, wind, and hydro. They are very concerned 

about the variable production from renewable sources. The northern Germany grid system has a 

large fraction of renewable generation and is already becoming unstable, threatening 
5

destabilization of neighboring grid systems. Nuclear hybrid energy systems can help stabilize the 

grid, remaining economical by making easily stored liquid synthetic fuels when their output is 

not needed for electricity production. Liquid fuels will be required for quite some time (e.g., for 

aviation). Even if those synfuels are expensive, perhaps the equivalent of petroleum at $200 per 

barrel, having the technology developed and operating puts a strategically valuable known cap 

on the economic damage that can be inflicted on a country by petroleum supply interruptions. 

Over the long run, the development of nuclear plants should optimize both core physics (for 

generating medical or industrial isotopes, or ‘burning’ nuclear byproducts) and energy

production (as heat, power, or both). LeComte noted that small nuclear plants are capital 

intensive and regular-sized plants are cheaper to run than small plants. However, it is expensive 

to transport high-temperature heat for use in a hybrid system so the chemical process is best built 

adjacent to the heat source. The challenge is to make efficient and effective chemical plants to be 

part of nuclear hybrid systems. 

2.8 Prospects for Nuclear Hybrid Systems

A thorough overview of many possible applications of nuclear heat was provided by Henri Safa 

of Commissariat à l'énergie atomique et aux énergies alternatives (CEA), the French nuclear and 

alternative energy agency. Hydrogen production using the sulfur-iodine process was explored by 

a team of CEA, General Atomics, and Sandia National Laboratory but was projected to be 

significantly more expensive than high temperature steam electrolysis. Second generation 

biofuels are under active research in France. Two of the three candidate biofuel processes are 

thermochemical routes based on synthesis gas. The SYNDIESE project will demonstrate the 

complete biomass-to-liquids conversion, including a world’s first demonstration of the use of 

external hydrogen to improve process efficiency. A survey of industrial energy use in France 

showed that about 40% of consumption is heat at less than 400°C. The energy needs of a large 

oil refinery, including power, steam, hydrogen, and water, could be met by a single 600 MWe 

sodium-cooled fast reactor operating at 500–600°C. Finally, district heating is an attractive and 

growing market suitable for low-temperature nuclear heat. Supplying this heat from the lowtemperature end of a power cycle reduces electricity production, but this is more than offset by 

the revenues from supplying steam at 2 bar pressure for heat. This low temperature heat can be 

economically transported for long distances, with one example presented assuming 150 km. All 

of these applications have the additional benefit of greatly reduced CO2 emissions compared to 

their conventional counterparts. 

2.9 NuRenew: Hybrid Nuclear-Renewable Energy Park

Bojan Petrovic of Georgia Tech made a brief presentation on NuRenew, a concept for an energy 

park that incorporates a molten-salt-cooled nuclear reactor, molten-salt-based CSP, and moltensalt-based thermal energy storage. The reactor could use thorium as fuel to address waste 

management issues. This hybrid energy system would provide electricity, transportation fuel, and 

high temperature process heat at about 600°C. It would enable re-purposing of fossil plant sites 

and coal infrastructure and would facilitate accelerated deployment of CSP. 

2.10 Nuclear-Renewable Production of Hydrogen and Syncrude

Charles Forsberg of MIT described two nuclear hybrid concepts producing hydrogen or synthetic 

crude oil from oil shale. The hydrogen system uses a high temperature electrolyzer to split water 

when excess power generation capacity is available, primarily for use in industrial markets. 

When peak power is needed, the electrolyzer is run in reverse to function as a fuel cell, 

generating power from the stored hydrogen. The dual functions improve the economics by using 
6

one device for both hydrogen production and peak electricity generation. In the oil shale system, 

a nuclear power plant generates load-following low-CO2 electricity, displacing an equivalent 

amount of fossil-fired, CO2-emitting power generation. When that nuclear electricity is not 

needed, the heat that would be used to generate it is instead diverted into heating a subsurface oil 

shale deposit. After several years of retorting at high temperature, the hydrocarbons in that 

deposit can be withdrawn as a synthetic crude oil. The credits for CO2 reductions obtained during 

the nuclear electricity production can be applied to the syncrude to allow it to meet low 

emissions standards increasingly being proposed and applied to vehicle fuels. In developing 

hybrid energy systems such as these, the institutional challenges of crossing established 

regulatory and business borders might equal the technical problems. 

2.11 Nuclear Hybrid Systems to Offset Variability of Wind-Generated Electricity

As the last technical talk before the breakout sessions, Richard Boardman of INL briefly 

described four increasingly complex hybrid system configurations that might be used to offset 

the variability of wind energy generation. Three of the four had a fossil-fired power plant as the 

heat source. Although nuclear systems would be the best way to avoid CO2 emissions, it is likely 

that initial hybrid systems will be fossil-fired to simplify those demonstrations and to allow

continued development and licensing of the next generation of reactors. 
7

3 Breakout Sessions

The attendees broke into two self-selected groups for in-depth discussions. One group, 

moderated by Shannon Bragg-Sitton of INL, covered thermal energy management issues with a 

focus on technology at the scale of unit operations. The second group, moderated by Robert 

Cherry of INL, covered system operations issues such as technical and economic analysis, 

system controls, and regulatory and market challenges. Their major points were reported to the 

full workshop using the presentations in Appendices C and D, respectively.

3.1 Thermal Energy Management

The thermal energy management group covered a range of topics including possible applications 

of hybrid systems, issues with use of a nuclear reactor, transport and storage of thermal energy, 

chemical conversion processes, and material problems at high temperatures. Their resulting list 

of priority research topics is reported in Appendix C. It includes equipment coupling, thermal 

energy storage (including the tradeoff of additional storage versus faster system dynamics to 

enable better load-following), developing methods for carbon-free hydrogen production, 

identifying additional ways to exploit excess heat or electricity, and development of heat transfer 

fluids. 

3.2 System Operations

The system operations group identified technical gaps in a variety of system-level issues. A 

partial list of the R&D recommended to address these gaps includes additional economic and 

feasibility studies on alternative configurations, rationalization of the different methods and 

criteria for assessing projects used by the different industries that currently run the technologies 

that would be combined in a hybrid system, coordination of the multiple control systems in 

interacting subcomponent processes, the role of energy storage capacity in improving dynamic 

response, and understanding what options (including retrofits of existing power plants) are 

feasible for demonstration in the near-term and how they might facilitate eventual 

commercialization. The topic of the interplay between energy storage and dynamic 

responsiveness was independently identified by both breakout groups.
8

4 Group Discussion

The first round of discussion covered topics that might have been missed or not fully described 

by the two breakout groups. Collected into related issues, these included:

What problem are we trying to solve? Hybrid system developers need to clarify 

their objective(s), which might include lower cost of energy, reduced imports, or 

energy security. They must understand and explain the solutions in a compelling 

manner. Transportation fuels will be important because purchases of oil from 

foreign countries reduce job opportunities here by sending dollars overseas. 

Stable and predictable fuel prices are also important. There are other opportunities 

related to generation and use of heat, especially using low-temperature heat for 

space and district heating and developing ways to do load-leveling with either 

thermal or nonthermal (such as wind) energy sources. Addressing complex mixed 

regulatory issues so these systems can be built will be difficult. Careful validation 

of analysis methods developed to let scaled-down tests be applied to novel fullscale designs will be important. 

Who should participate? Industry buy-in will be important because they will 

commit to and execute the projects. The chemical or fuel outputs of hybrid energy 

systems will have to be integrated into the chemical and petrochemical supply 

chains, so those industries as well as traditional fossil energy firms that operate in 

these markets could productively be involved. The solar photovoltaic industry 

also has variability problems that might be addressed by hybrid energy systems. 

Other potentially interested industries should be identified. The Department of 

Energy program to develop high-temperature gas-cooled reactors has been in 

recent years pursuing a similar technology development and commercialization

effort. Understanding their experience could be useful.

What communications and outreach are needed? The policy world is the means 

by which the government will learn of and support hybrid energy system 

development and implementation. However, policy analysts as a group lack an 

understanding of technical issues. Hybrid system supporters need to provide the 

policy world with a simple cohesive message that provides answers to current 

problems and can be communicated to Congress and the administrative branch. 

Recalling President Obama’s statement that the country’s energy problems 

require an “all of the above” approach, hybrid systems might represent 

“integration of all of the above.” Ultimately, though, the energy industry must 

make the decision to build and operate hybrid energy systems, possibly in 

response to policy incentives. 

Because many different hybrid energy systems with different combinations of technologies are 

possible, it is necessary to have criteria for selecting those that are most attractive. This selection 

will naturally depend on the stakeholders participating. Metrics for these criteria for various 

hybrid system configurations will have to be developed. The criteria proposed included the 

following, which have been collected into categories of related issues:
9

Development risks: Managing development risk, capacity for staged 

demonstration and evolutionary development, limited complexity, good 

controllability, and near-term deployability.

Project economics: Cost (business case, capital cost, return on investment), ability 

to finance large capital costs, initial deployment location (optimal siting to 

address the multiple feed and product streams, choice of building in developed

versus developing countries), and end-user needs.

Sustainability issues: Greenhouse gas emissions, fossil energy use, feedstock 

consumption, water withdrawal and consumption, long-term availability of 

resources, and land requirements.

National policy issues: Value to the nation outside of immediate project 

economics, energy security, flexibility to use different feeds or make different 

products that might be mandated by future policies, value in niche markets of a 

few such plants, and transparency in reaching policy decisions.

In addition to the characteristics of the possible configurations, the choice of specific primary 

energy sources or energy products is clearly important. The workshop attendees proposed 

candidates that may be of greater initial interest because of regional needs or available resources. 

These sources and applications include:

• Sources

o An architecture that would enable renewable energy use on the grid at levels 

above 25%

o Geothermal hybrid systems must address economic problems resulting from 

low temperatures and small plant capacities

o Lower capital cost, small modular nuclear reactors

o Natural gas as a plentiful, low-cost input used for thermal energy or for 

feedstock to make synthetic fuels or hydrogen

o Retrofit of hybrid systems onto existing plants 

o General Electric natural gas/solar concept but with integrated energy 

storage 

o Existing coal coordinated with wind 

o Coal with solar thermal

• Products

o Early systems using combined heat and power with thermal storage 

o Replacing power production from aging coal plants

o Desalination 

o Synthetic fuel production via nuclear power 

o Use of CO2 captured from fossil-fired power plants to make synfuels.
10

5 Resulting Call for Proposals

Immediately after the workshop, the results were used to generate a call for INEST preproposals

related to nuclear hybrid energy systems. The text of that call is presented in Appendix E. The 

requested topic areas were:

• Nuclear hybrid design concepts and analyses to identify and understand alternative 

new configurations

• Temperature boosting to raise the relatively low temperature (270–300°C) thermal 

output of light water reactors to higher levels, 500–800°C or more, to make that heat 

more generally useful for synthetic fuels processes; many of the most advanced 

concepts for small modular reactors are pressurized light water reactors

• Hydrogen production using nuclear energy, possibly combined with concepts from 

the first two topics in this list, would be useful for synfuel production

• Policy strategies for integrating the disparate technologies and regulatory paradigms 

associated with complex, integrated nuclear hybrid systems and that address key nontechnical challenges to fielding such a system.
11

Appendix A. Workshop Agenda

Hybrid Energy Systems Workshop 

April 3-4, 2012

Salt Lake City Marriott Downtown

Day 1

7:30 am Breakfast/Welcoming Remarks Steve Aumeier (INL)

Charles Forsberg (MIT)

8:15 am Participant Introductions All

8:30 am Overview of INEST and JISEA Marsha Lambregts (INEST)

Doug Arent (JISEA)

8:45 am Grand Energy Challenges Doug Arent (JISEA)

9:00 am A Wyoming Case Study Bob Ballard (U of Wyoming)

9:25 am Overview of Hybrid Systems in China Zhiyuan Zhu (Chinese 

Academy of Sciences)

9:50 am An Industrial Perspective on Hybrid Energy Max Peter (General 

Electric)

10:15 am Break

10:30 am Summary of 2011 JISEA Workshop Mark Ruth (NREL)

10:55 am Nuclear Power Plants with Thermal Energy 

Storage

Paul Denholm (NREL)

11:30 am Nuclear Reactor Technologies for Hybrid 

Applications

Michel LeComte (AREVA)

11:45 am Prospects for Nuclear Hybrid Systems Henri Safa (CEA)
12

12:10 pm Working Lunch

NuRenew: Hybrid Nuclear–Renewable Energy 

Park

Nuclear-renewable Production of H2 and 

Syncrude

INL Hybrid Energy Program

Bojan Petrovic (Georgia 

Tech)

Charles Forsberg (MIT)

Richard Boardman (INL)

1:30 pm Break

1:40 pm Outline “Example” Hybrid Energy Systems Richard Boardman (INL)

1:50 pm Discussion Objectives Shannon Bragg-Sitton (INL)

2:00 pm Group Discussion

Breakout 1: Thermal Energy Management 

Breakout 2: System Operations

• Identify R&D challenges and technology 

gaps

• Prioritize challenges

Shannon Bragg-Sitton (INL) 

Robert Cherry (INL)

3:15 pm Break

3:30 pm Group Discussion

For each topic area:

• Identify research activities

• Prioritize research activities

4:50 pm Discussion Wrap-up and Summary Richard Boardman (INL)

5:00 pm Reception and Networking Opportunity

Casual Discussion of Break-out Results

Day 2

7:30 am Breakfast/Discussion of Break-out Results

System Level Control System Needs

Shannon Bragg-Sitton (INL)

Robert Cherry (INL)

9:30 am Panel Discussion: Successful Public/Private 

Partnerships

Moderator: Richard 

Boardman (INL)

10:00 am Opportunities for Research Partnerships

• INEST and NEUP
13

• JISEA

• LDRD program

• Program development funds

• Faculty-Staff exchanges

• Public/Private partnerships

• NEUP proposal highlights

“Potential Characterization & Operation of 

Hybrid Heat Transport & Energy 

Conversion Systems Using Intelligent 

Control” (Akira Tokuhiro)

Marsha Lambregts (INEST)

Doug Arent (JISEA)

11:00 am Closing Remarks Steve Aumeier (INL)

11:15 am Break/Networking and Individual Discussions

12:00 pm Steering Committee Meeting
14

Appendix B. Attendees

Hybrid Energy Systems Workshop

Attendees List

April 3-4, 2012

Mark Antkowiak NREL Mark.Antkowiak@NREL.gov

Doug Arent JISEA pamela.lee@nrel.gov

Steven Aumeier INL steven.aumeier@inl.gov

Robert Ballard Jr U of WY rballar2@uwyo.edu

Heng Ban Utah State University heng.ban@usu.edu

James Bartis RAND bartis@rand.org

David Bell U of WY davebell@uwyo.edu

Richard Boardman INL richard.boardman@inl.gov

Shannon Bragg-Sitton INL shannon.bragg-sitton@inl.gov

Robert Cherry INL robert.cherry@inl.gov

Benjamin Cross Savannah River Nat. Lab Ben.Cross@srnl.doe.gov

Larry Demick INL Laurence.Demick@inl.gov

Paul Denholm NREL paul.denholm@nrel.gov

Linda Elliott INL linda.elliott@inl.gov

Marvin Fielding Schiess & Associates mfielding@schiesseng.com

Charles Forsberg MIT cforsber@mit.edu

Humberto Garcia INL Humberto.Garcia@inl.gov

Maximilian Gorensek SRNL maximilian.gorensek@srnl.doe.gov

James Herzog INL james.herzog@inl.gov

John Hess INL jrichard.hess@inl.gov

Robin Hurless U of WY rob.hurless@wyo.gov

Jeffrey King Colorado School of Mines kingjc@mines.edu

Marsha Lambregts INL marsha.lambregts@inl.gov

Michel LeCOMTE AREVA Michel.lecomte.ext@areva.com

Gloria Newberry INL gloria.newberry@inl.gov

John Nowoslawski State of Utah jnowoslawski@utah.gov

Andrew Peter GE Global Research peter@research.ge.com

Bojan Petrovic Georgia Tech bojan.petrovic@gatech.edu

Craig Rieger INL craig.rieger@inl.gov

Mark Ruth NREL mark.ruth@nrel.gov

Piyush Sabharwall INL Piyush.Sabharwall@inl.gov

Henri SAFA CEA henri.safa@cea.fr

Christopher Saffron MSU saffronc@msu.edu

Beth-Anne Schuelke-Leech The Ohio State Univ schuelke-leech.1@osu.edu

Vijay Sethi Western Research Institute vsethi@uwyo.edu
15

Carl Stoots INL carl.stoots@inl.gov

Xiaodong Sun The Ohio State University sun.200@osu.edu

Doug Taylor INL doug.taylor@inl.gov

Akira Tokuhiro University of Idaho tokuhiro@uidaho.edu

Pavel Tsvetkov Texas A&M University tsvetkov@tamu.edu

Vivek Utgikar University of Idaho vutgikar@uidaho.edu

James VanDerwerken GE Global Research vanderwerken@ge.com

Alan Walker USTAR alanjwalker@utah.gov

Joshua Walter TerraPower jwalter@terrapower.com

Charles Weingartner DOE-ID weingacb@id.doe.gov

Zhiyuan Zhu

Shanghai Branch, Chinese 

Academy of Sciences zhuzy@shb.ac.cn
16

Appendix C. Thermal Management Breakout Discussion

Thermal Energy

Breakout Session

April 3, 2012

Discussion Points

 Base Thermal Generation

– Reactor Concepts / Modularization

– Fossil and Renewable Concepts

 Thermal Energy Transport

– Heat Deposition to Process

– Thermal Hydraulics

– Heat Exchange

– Heat Upgrading

 Thermal Energy Storage

 Chemical Energy Conversion

– Hydrogen Generation

– Liquid Fuel Production

– Fossil Fuel Extraction and Processing

 Materials & Equipment Fabrication

– High Temperature Systems

– Component Fabrication

2
17

What problem are we trying to solve?

What is the MARKET size for each “problem”?

– Dictates R&D funds available

What can be uniquely solved by hybrid energy systems?

Problems to address:

 Need for hydrogen production

– Clean process (reduced GHG emissions)

– Consider resource needs / availability (i.e. water)

 Uprating of fuels

 Shale oil extraction – huge market

 Increased efficiency

 Multi-purpose reactors: Entry of nuclear energy into the 

transportation industry

3

Base Thermal Generation

 Reactor selection cannot be custom for a given process 

 Generally assume steady state only: Desire to place flexibility 

downstream of reactor (chemical plant or thermal storage)

 Resource utilization / siting needs 

 Trade study: 

Address what concepts are feasible when coupled with energy storage 

and chemical applications (consider dynamic linkages)

 Trade study: 

Thermally coupling of various reactor types to different processes –

economics, licensing, risk assessment, technical issues, siting...

 Low temperature generation: (nearer term applications)

– Possibly more closely coupled than high T generation systems

– Gap: Is the heat of sufficient quality for desired tasks?

– Gap: Temperature upgrading

 High temperature generation:

– Higher efficiency

– Possibility for air cooling

– Gap: Efficient heat transmission 5
18

Thermal Energy Transport

 Thermal coupling

– Importance of thermal interface – possible scaled demonstration of 

thermal coupling solutions?

 Need a clear understanding of customer needs, market needs

 Heat upgrading trade study: Methods to increase steam 

temperature to enable more process applications

 Different technology routes depending on scale of the operation

 Heat exchanger designs

 Working fluid characterization

 Feedback / sub-system interaction – Nuclear plant – chemical plant feedback and sub-system prioritorization

(NPP – grid – CP)

– Safety issues, licensing mandates

 Possible early demonstration: 

Nuclear plant coupled to a chemical process (single input / 

single output) 6

Thermal Energy Storage

 What is the thermal energy storage capacity requirement? 

 General Requirements

– Enable load following

– Maintain consistent reactor inlet temperature

– Match sub-system time constants (energy storage, reactor, chemical 

plant, grid)

– Provide high density storage medium (e.g. liquid hydrocarbons)

 Possible solutions

– Molten salts as storage medium (leverage solar thermal programs)

– Phase change materials with high heat capacity

 Research Areas:

– Thermal storage systems specifically coupled to a reactor

– Development of highly dense storage systems

7

Chemical Energy Conversion

 Negative electric prices (i.e. paying the grid for power) –

what can we do with the excess electricity?

 Reduce capital cost of processes

 Commodity production and storage – what makes sense?

– Methanol, ammonia, hydrogen, syncrude...

Research Areas:

 Hydrogen generation for multiple applications

 Hydrogen storage and transport (gas vs. liquid)

 Electrolysis (QC, cell durability, scale-up, on-line maintenance)

– GOAL: Reduce capital costs for electrolyzers

 CO production

– CO2 source?

 Liquid Fuel Production

– Require H2 for higher density fuel and syngas production

 Fossil Fuel Extraction and Processing 8
19

Materials and Equipment Fabrication

 High temperature systems face increased materials challenges

 Concern: Material availability and qualification

 Research areas:

– Working fluids:

• Analysis of working fluid chemistry and properties and effect of 

structural materials

• Process control – impurities, chemistry control

• Freeze-thaw issues for some working fluids (i.e. molten salts)

– Heat exchanger design (conventional vs. advanced)

• Stress-corrosion cracking

• Design reliability

– Equipment for heat transport over long distances

9

Identified Key Research Areas

 NHES sub-system interfaces – specific focus on coupling

– Thermal coupling of different reactor concepts

– Dynamic links for different reactor designs

 Economics and technical challenges of transporting heat (high 

vs. low T, distances)

 Thermal storage options – requirements, scalability for 

demonstration (high volume to surface area ratio)

 Parametric and sensitivity study for working fluid selection, 

material compatibility

 Integrated system operations to demonstrate system coupling 

solutions, thermal energy transfer, storage, etc.

– What can be learned from a small-scale hardware demonstration?

– What is the scalability of sub-systems? 

– What will provide reasonable accuracy / understanding of system 

operation? 10

Priority Research Areas

 Equipment Coupling

 Thermal Energy Storage – coupling to a nuclear reactor 

(consideration of temperature and capacity)

 Methods for efficient carbon-free hydrogen production 

(sustainable and economical)

 Methods to exploit excess heat / excess electricity

 Heat transfer fluid development, characterization

11
20

Appendix D. System Operations Breakout Discussion

Modeling, Integration, Optimization

Microeconomic Analysis (to guide investments in R&D)

GAP: Additional objective economic feasibility studies need to be done

RESEARCH TOPIC: Analysis of inputs and outputs and capital for the potential HES 

(identify near-term winners with today’s incentives and longterm, high payoff)—including energy security, environments, 

social, political, economic , etc.

Technical Analysis 

GAPS: 

• Heuristics to prioritize and screen alternatives (development of criteria)

• Different industries coming together who have different basis for design 

and different systems analysis tools which must be integrated and used to 

model the whole system --Need improved computer simulation tools (e.g., 

need to be adapted to power systems—multi-domain dynamic analysis)

RESEARCH TOPIC: 

• Assemble stakeholders to develop criteria and identify heuristics 

(prioritize)

• Develop open computational tool set for analysis of the dynamic system 

System Monitoring & Control (Instruments & Operators)

Human Factors 

GAP: Coordination between multiple control systems--interaction between the 

different systems 

RESEARCH TOPIC: Preliminary investigation of current analogs – petrochemical 

plants or flight control systems

Instrumentation

GAP: Sensors needed to measure --- contamination leaking back into the nuclear 

side

RESEARCH TOPIC: Identification of issues that require sensors (e.g., 

contamination or interferences) and or interpretive algorithms 

(e.g., diagnostics/ prognostics)

Dynamic System Modeling

GAP: Lack of ability to predict and model the interaction of the application of 

the various systems you are using

RESEARCH TOPIC: Develop open computational tool set for analysis of the dynamic 

system (see above--repeat) 
21

Grid Management 

Intermittent Generation 

GAP: Need for stable output – how might HES be operated to stabilize the grid (responsive 

to changes in demand and variability)

RESEARCH TOPIC: Looking at HES in context of national grid management goals (relates to 

research bullet 1 above) 

Electrical Power Transmission 

GAP: Siting—using different resources, different products—how to optimize siting decisions

RESEARCH TOPIC: Computational/system model/matrix of the HES (providing the range of 

options) to increase understanding of how adding systems increase 

complexity (regional basis)

Energy Storage/Batteries 

GAP: Determining storage levels (capacity) and which technologies should be used, what is 

sufficient?

RESEARCH TOPIC: Sweet spot analysis of storage capacity versus system flexibility/response

Sociopolitical & Financing Challenges

Regulatory/ Licensing/Safety 

GAP: Different regulatory and design codes for nuclear, electrical and chemical 

RESEARCH TOPIC: Identification of policy/regulatory conflicts and commonalities among the 

various agencies 

Market Challenges 

GAPS: 

• Understanding of near-term options versus long-term options and emerging 

technologies and what steps are required to get commercial scale production 

• Ability to retrofit versus new construction

RESEARCH TOPIC: Develop roadmap of technologies

Life Cycle Assessment 

GAP: Lifecycle analysis of each system 

RESEARCH TOPIC: Review status of baseline technology and LCAs (identify where they are today 

to do a comparative) 
22

Appendix E. INEST Call for Proposals on Nuclear Hybrid Systems

Institute for Nuclear Energy Science and Technology

2013 LDRD Call

Point of Contact: Marsha Lambregts, 526-1336, Marsha.Lambregts@inl.gov

Summary:

The Institute for Nuclear Energy Science and Technology (INEST) will sponsor and oversee laboratory 

directed research aligned with the strategies of four Centers of Research and Education (CORE): Fuel 

Cycle, Nuclear Fuels and Materials, Safety and Licensing, and Space Nuclear Power. Additional 

information about INEST and the COREs can be found at: 

https://inlportal.inl.gov/portal/server.pt/community/institute_for_nuclear_energy_science_and_technology/

692/home. The criteria to be used in selection of the LDRD proposals are:

Essential

1. Technical merit

2. Develop capabilities supportive of INEST CORE strategies

3. Strengthen collaborations with universities

Additional

4. Attract expertise to INL

5. Encourage student participation

Specific guidance in each area is provided below:

[Four other technical areas deleted here]

Nuclear Hybrid Energy Systems CORE LDRD Call

Contact: Steve Aumeier, 526-6997, Steve.Aumeier@inl.bgov

Estimated budget $250K for FY2013

U.S. energy security objectives (DOE Report on the First Quadrennial Technology Review, September, 

2011) highlight the need for lower carbon, domestic energy options for both stationary power generation 

and transportation systems. In the former, objectives call for deriving 80% of America’s electricity from 

clean-energy sources by 2035, while improving the modularity, scalability, and infrastructure compatibility 

of clean-electricity-supply technologies and reducing greenhouse gas emissions by 83% by 2050 (from a 

2005 baseline). Renewable electric generation and small modular nuclear reactors (SMRs) are each 

identified as a priority focus for clean power generation, with energy storage for excess power generation 

specifically mentioned as a need. Transportation system objectives are tied fundamentally to goals of 

reducing greenhouse gas emissions and reducing the import of oil sources from overseas. Resulting 

objectives cover multiple pathways, including vehicle efficiency, fuel switching (e.g., electric and hybridelectric vehicles, natural gas vehicles), biofuels, and synthetic fuels with low life-cycle carbon 
23

characteristics. Tangential to these outcomes are objectives to increase domestic manufacturing and 

export of U.S. manufactured products. Significant barriers to meeting these objectives include:

1. Large scale renewable electric generation can introduce significant intermittency in generation 

resulting in grid management, stability, and control challenges as well as resource utilization 

inefficiencies (low capacity factors);

2. Transportation fuels sourced from domestic carbon must have lower life-cycle greenhouse gas 

emissions than oil-derived fuels; electrification and natural gas vehicle introduction will take many 

years to fully deploy and will not displace the need for liquid transport fuels; cost effective biofuels 

production at scale will take much more time and development to realize;

3. Nuclear energy, including SMRs, deployed in present operational paradigms (baseload electricity 

generation) are fundamentally limited in their ability to impact the broad transportation market and 

do not enable greater penetration of renewable energy or management of the increasingly 

dynamic electric grid.

Proposals are thus encouraged in the following areas:

Nuclear Hybrid Design Concepts and Analyses: Proposed nuclear hybrid energy system architecture 

concepts and related analyses should:

1. Have a reasonable opportunity to produce 5 million barrels per day of liquid transportation fuel 

(approximately 80% of present oil import derived fuels) or their precursors that are compatible 

with the present infrastructure;

2. Utilize domestic carbon resources (coal, shale, or biomass-derived);

3. Directly incorporate or enable efficient grid introduction of intermittent renewable electric 

generation (solar, wind, or geothermal);

4. Demonstrate greenhouse gas emissions reduction for transport fuels and electric generation of 

greater than 25% from present levels;

5. Demonstrate, via integrated electricity and chemical production, how (3 and 4) above are 

achieved, how the nuclear island would be configured (number of reactors, grid integration, 

reactor / chemical plant operation paradigm, etc), sourcing of carbon, and related attributes;

6. Have potential for economic deployment via efficient heat and electrical energy integration within 

the system Proposals should address key enabling technology challenges, potential expansion of 

the SMR market as compared to baseload electric markets, and other attributes. Researchers are 

encouraged to examine published work on hybrid systems design and attributes (see list of 

references below).

Temperature Amplifying: Proposals that provide options for and assess implications of boosting the 

reactor outlet working fluid energy. Concepts are sought that could efficiently and effectively (in terms of 

cost, greenhouse gas emissions, and practical deployment potential) raise the temperature of a liquid or 

gas energy carrier from 250°C to 500-800°C (plus) in a manner suitable for use in an industrial process 

via a hybrid nuclear energy system;

Hydrogen Production via Nuclear Energy: Novel H2 production techniques that could be integral to 

systems described in (A) and/or using techniques as called for in (B);

Policy Strategy: Proposals that develop technical and sociopolitical strategies for integrating the 

disparate technologies and regulatory paradigms associated with complex, integrated nuclear hybrid 

systems are encouraged. Policy-related proposals should address key non-technical challenges to 
24

fielding a nuclear hybrid energy system and should propose research that will allow those challenges to 

be surmounted in a time and cost-efficient manner.

References: (Contact Richard Boardman 208-526-3083/Richard.Boardman@inl.gov for electronic 

copies)

DOE Report on the First Quadrennial Technology Review, September, 2011

Energy and Environmental Science, Large HES for Making low CO2 load-following power and 

synthetic fuels

Energy Policy, Using Excess Electric Generation Capacity to Make Synthetic Fuels at the 

National Scale

Energy, Multiple Hybrid Energy Systems for Load-Following and Offsetting Renewable 

Generations Variability

Energy, Dynamic Analysis of Hybrid Energy Systems under Flexible Operations and Variable 

Renewable Generation

Energy, Development of Multifunctional Energy Systems (MES)

INL/EXT-09-16942, Integration of High Temperature Gas Cooled Reactors into Industrial Process 

Applications

INL/EXT-11-23008, Integration of High Temperature Gas Cooled Reactors into Selected 

Industrial Process Applications

LBNL-1248E, Advanced Coal Wind Hybrid: Economic Analysis

ICAPP 2012, A Nuclear Wind/Solar Oil-Shale System for Variable Electricity and Liquid Fuels 

Production