# Presentation: 029522

## Fusion as a Source for Hydrogen Production

**Mike Campbell and Ken Schultz**
**General Atomics**
**13 December 2004**
**25th Annual Fusion Power Associates Meeting**

## Hydrogen is the desirable  Replacement for Fossil Fuels

- •  **Hydrogen can reduce CO****2**** emissions and dependence on fossil fuels**
-      **— ****No greenhouse gases. Hydrogen produces only **
**	****	****water as the “waste product”**
**	****— ****In a fuel cell, hydrogen could get **
**	****	****twice the efficiency as a gasoline engine**
**The President is supportive**
**	****of a *****Hydrogen Economy***
** **

**2003 "State of the Union Address” **
- With a new national commitment, .... the first car driven by a child born today could be powered by hydrogen, and pollution-free...

## Question:  Where to get the hydrogen?

**Hydrogen is an energy carrier, not an energy source**
**While hydrogen is the most abundant element, most is chemically bound as hydrocarbons, carbohydrates or water**
**Energy is needed to extract the hydrogen**
**Most hydrogen today is made from fossil fuels**
**Steam reformation of methane primary source  **
**CH****4**** + 2H****2****O + heat ******** 4H****2**** + CO****2**** **
**if heat from CH****4****: more CO****2**** released, ~3 H****2**** per CO****2**
**A Hydrogen Economy only makes sense if hydrogen is produced with non-fossil, non-greenhouse gas energy**
**Our options for clean energy are limited**
**Nuclear fission, Solar, Renewables,”clean coal” — *****and Fusion!***
**There is a potential  long term opportunity for fusion**

## Fusion 

**The President recognizes Fusion’s potential...**

## The Hydrogen Economy will need a lot of hydrogen

**US use now 11 million tons H****2****/y (48 GWt)**
**95% produced from Natural Gas (~6% of total use)**
**Steam Methane Reformation (SMR) ****	****	****	****	****CH****4**** + 2H****2****O + E = 4H****2**** + CO****2**
**Releases 74M tons CO****2****/yr**

**Most is used in NH****3**** and oil industries**
** ****~10%/y growth ******** X 2 by 2010,**
**	****	****	**** ****X 4 by 2020**

**  ****Hydrogen Economy will need much more**
**  ****X 18 for transportation –– 200 M tons/year, ~900 GWt/********	**
**  ****X 40 for all non-electric energy**

## DOE Hydrogen Program

**$1.2 Billion over five years (FY 2004-2008)**
**Production goal - provide multiple feedstock options to fuel hydrogen economy**
**Significant cooperation between offices**
**Energy Efficiency & Renewable Energy (EE)**
**Fossil Energy (FE)**
**Nuclear Energy, Science & Technology (NE)**
**Science (SC)**
**Management, Budget & Evaluation (ME)**
**EE has responsibility for coordinating overall DOE Hydrogen Program and R&D on delivery and infrastructure issues – $257M/yr**
**NE has responsibility for R&D on production processes most suited for nuclear applications – $7M/yr-****underfunded!!!**
**SC has responsibility for R&D on fusion hydrogen activities**
**Currently none **

## Fusion could produce the hydrogen 

**FAME (****Fusion Applications and Market Evaluation) ****identified hydrogen as a useful product ****— 1988**
**Electricity**
**Fissile fuel and tritium***
**Radioisotopes (esp. Co****60****)***
**Fission waste burning***
**Synthetic fuels (****hydrogen****)**
**District and process heat***
**Rare metals***
**Space propulsion**

***: Most require co-generation of electricity**** **

**More recent Sheffield JIEE and ARIES studies agree**

## Fusion can provide hydrogen by several routes

**Electric power generation ******** Electrolysis**
**Proven technology**
**Overall efficiency ~24% (LWR),  ~36% (Hi T Reactors)****        ****	****	****	**** ****(efficiency of electric power generation x efficiency of electrolysis****)**
**Electricity + Heat ******** ****	****High temperature electrolysis or ****	****	****	****	****     ****	****Hybrid thermochemical cycles**
**Need both electricity generation and high temperature process heat**
**Efficiencies up to ~ 50% **
**Developing technologies**
**High temperature heat ******** Thermochemical water-splitting**
**A set of chemical reactions that use heat to decompose water **
**Net plant efficiencies of up to ~50%**
**Developing technology**
**Are there fusion-unique processes?**
**	**

## Thermal processes use fusion for high temperature process heat

**80% of fusion energy is carried by 14 MeV neutrons**
**Neutrons can penetrate cooled structure, deposit heat in insulated interior high temperature zone**
**Extreme temperatures possible in principle**
**Fusion neutrons also create challenges:**
**Neutrons are needed for tritium production**
**6****Li +  n= T + He, ****7****Li + n = T + n’ + He; (n, 2n) reactions possible**
**Tritium contamination of product must be avoided**
**Tritium is very mobile, especially at high temperature**
**Clean-up of contaminated H****2**** would be impractical**
** ****Neutron activation can contaminate process fluids**

## HTE offers potential high efficiency at high temperature

**Electrolysis at high T substitutes heat for electricity **

- Figs. Courtesy of S. Herring, INEEL

**Overall energy requirements for high temperature electrolysis.**

**Efficiencies of electricity and hydrogen production.**

## HTE could benefit from fusion’s high temperature capability

## High temperature electrolysis used fusion heat and electricity from separate blanket modules

**HYFIRE tokamak concept used 2 blanket modules**
**1400-1800oC steam-cooled HTE module**
**800-1000oC He-cooled power module**
**External electrolysis**
**High heat to hydrogen efficiencies claimed:**
**1800oC/60% pcs gives ~70%**
**1400oC/40% pcs gives ~50%**
**“****Significant development   required”.....**

**BNL HYFIRE study 1979**

## Thermochemical water-splitting offers high efficiency

**A set of coupled, thermally-driven chemical reactions that sum to the decomposition of water into H****2**** and O****2**
**All reagents returned within the cycle and recycled**
**Only high temperature heat and water are input, only low temperature heat, H****2**** and O****2**** are output – literally no effluents**
**High efficiency is possible  **
**But high temperature required **
**Aggressive chemicals used**
**A developing technology**
**Explored extensively in the 1970s**
**Numerous possible cycles identified**
**Never commercialized**

## The S-I cycle is the lead thermochemical candidate in the US, Japan and France	

** ****Invented at GA in 1970s**
**Serious investigations for nuclear and solar**
**Chemistry reactions all demonstrated**
**Materials candidates selected and tested**
** ****Advantages:**
**All fluid continuous process, chemicals all   recycled; no effluents**
**H****2**** produced at high pressure **
**Highest cited projected efficiency, ~50%**
** ****Challenges:**
**Requires high temperature, ≥800°C**

**Sulfur-Iodine Thermochemical **
**Water-splitting Cycle**

**Glass Chemistry loop in operation in Japan producing ~50 liters/hr**

## Fusion Thermochemical SI-H2 Concept used only high temperature heat

## Thermochemical water-splitting uses only heat in two coolant streams to control tritium

**Single blanket module with two coolant streams**
**High temperature He stream recovers 30% of heat at 1250oC**
**Tritium breeding zone yields 70% at 450oC**
**Match to Sulfur-Iodine cycle**
**Projected efficiency 43% and ~ $2.00/kg H****2**
**He flows directly to H****2**** process**
**Slip-stream processing and SiC HX limit release below limits for unrestricted use**

**GA Utility Synfuel Study, 1983**

## Effort will be needed to achieve practical hydrogen production from nuclear energy

**The first steps have begun:**
**Demonstrate laboratory scale SI process operation (I-NERI: SNL, GA, CEA)**
**Measure needed chemical data (SNL-L, CEA)**
**Tasks could be completed in 3 years **
**Next, build a ~10 MWt Pilot Plant (~3 tons/day of H****2****)**
**Design, build and operate in ~4 years**
**Operation with fossil-fueled simulated nuclear heat source**
**Then, build a H****2****- Nuclear Demo Plant**
**Part of Idaho “Next Generation Nuclear Power” Demonstration Project**
**Demonstrate Nuclear Production of Hydrogen by ~2015 **

## NGNP plans to demonstrate nuclear production of H2 at INL by 2017

**DOE Plan:  Demonstrate S-I thermochemical water-splitting and high temperature electrolysis processes at Idaho National Laboratory**

**Provide 60 MWt of heat for hydrogen production**
**Allow smooth transition between 100%   electricity and 90% electricity/10% hydrogen**
**Up to 20 tons of H****2**** per day **
**Demonstrate prevention of failure propagation across reactor/process interface**
**Maintain hydrogen purity**
**Tritium release below NRC and EPA standards**
**Radioactivity in hydrogen below 10CFR20 limits**
**Hydrogen meets fuel cell standards**

**These technologies could be used with a fusion heat source**

## Economics of hydrogen production are challenging

**H****2**** currently made from natural gas by steam reformation**
**At current ~$6.50/MBtu cost of NG, H****2**** costs ~$1.50/kg or $11/MBtu**
**Production of H****2**** from fission projected to cost ~$1.40/kg**
**Could compete with natural gas today (at regulated utility capital rate)**
**O****2**** credit for nuclear or CO****2**** tax for fossil are possible**
**Fusion could compete if capital cost ≤ $500/kW****t**
**$3B for “n****th**** of a kind” 6 GW****t**** fusion process heat plant *****is *****a***** *****believable goal**

- Figure courtesy of EPRI
- $20/ton O2 credit, no CO2 penalty
- Regulated utility capital cost rates used, 12.6% CRF

## Low Temperature Electrolysis could be used; would  it be economical?

**Capital costs are coming down:**
**Current cost – >$1000/kWe**
**Production goal cost – $250/kWe**
**Potential ultimate cost – $50/kWe**
**Based on General Motor’s ultimate goal for fuel cells (similar technology)**
**Average electricity prices hurt economics of electrolysis**
**$1.5 - 2.0/kg of H****2**** needs 2-3¢/kWe-h electricity **
**6-7¢/kWe-hr implies$3.50-4.0/kg H****2**** cost**
**Off-peak pricing could have positive benefit**
**Operate electrolysis units only during off-peak hours**
**Electricity price might be only the fuel cost – very low for fusion**
**Would low off-peak rates compensate for lower capital utilization? **
**JIEE study was encouraging**
**Large plants with public utility financing and off-peak pricing look favorable**

## Hydrogen production could be a major role for Fusion

**Thermal processes — high temperature electrolysis, thermochemical water-splitting — are similar to fission application, will benefit from that development**
**Fusion can potentially provide higher temperatures, but has additional requirements and concerns**
**Tritium production impacts the fraction of heat delivered at high temperature — net thermochemical efficiencies ≤50%**
**Tritium control will have strict limits, will require innovative technology and design choices**
**Off-peak electrolysis production of hydrogen could be attractive**
**Allow large fusion plant to operate at 100%, electricity output to load follow**
**High value of H****2**** will benefit fusion economics**
**With development, fusion could help fuel the Hydrogen Economy**

## Off-peak hydrogen production costs

- Possible Off-Peak Price of Fusion Electricity?

- DOE Goal Cost of H2 $1.50/kg

**Electrolysis Capital Cost**