The Future of the Nuclear Fuel Cycle

Transcription

1 The Future of the Nuclear Fuel Cycle Results* and Personal Observations Charles W. Forsberg Executive Director MIT Nuclear Fuel Cycle Study Department of Nuclear Science and Engineering November 10, 2010 *M. Kazimi (Co-chair), E. J. Moniz, (Co-chair), C. W. Forsberg (Executive Director), et. al, The Future of the Nuclear Fuel Cycle: An Interdisciplinary MIT Study, Massachusetts Institute of Technology, Cambridge, MA, 2010

2 MIT undertook this study* to address two questions in the context of significant growth of nuclear power What are the long-term desirable fuel cycle options? What are the implications for near-term policy choices? *M. Kazimi (Co-chair), E. J. Moniz, (Co-chair), C. W. Forsberg (Executive Director), et. al, The Future of the Nuclear Fuel Cycle: An Interdisciplinary MIT Study, Massachusetts Institute of Technology, Cambridge, MA,

3 For the Next Several Decades, the Once- Through Fuel Cycle using LWRs is the Preferred Economic Option for the U.S. Accelerate implementation of first mover incentive program No shortage of uranium resources Scientifically sound methods to manage spent nuclear fuel exist (SNF) Resource extension and waste management benefits of limited recycling (MOX) are minimal Fuel cycle transitions take a long time: many LWRs and little difference in total transuranic inventories or uranium needs in this century in standard closed fuel cycle scenario 3

4 Finding: Uranium Resources There is no shortage of uranium that might constrain future commitments to build new nuclear plants for much of this century Recommendation An international program should be established to enhance understanding and provide higher confidence in estimates of uranium costs versus cumulative uranium production 4

5 Uranium Cost Assessment Uranium is 2 to 4% of the cost of nuclear electricity We evaluated uranium mining costs versus cumulative worldwide uranium production. Uranium resource estimates versus ore grade Economics of scale Technological learning over time Best estimate: The cost of uranium would increase by 50% (1 to 2% increase in electricity costs) if: Nuclear power grows by a factor of 10 worldwide Each reactor operates for a century 5

6 Price of 25 Metals Over a Century 1998 Dollars pe er Metric Ton Inflation Adjusted Year Uranium is a Metal: Expect Similar Behavior 6

7 Planning for Long Term Managed Storage of SNF For About a Century Should be Integral for Fuel Cycle Design Can and should preserve options for disposal, reprocessing, recycle Why? Major uncertainties for informed choices: NP growth? Nonproliferation norms?... Technical: Uranium resources? Alternative fuel cycles?.. Move to centralized managed storage: not for economics or safety (Does not imply storage for century move when path(s) forward understood) 7

8 It Will Be Decades Before We Know If LWR SNF Is a Resource or Waste LWR SNF has a high energy content Equivalent to super Strategic Petroleum Reserve LWR SNF could be a waste if Large uranium resources Not required for fast reactor (FR) startup FR use 50 times less uranium per kw(e)-hr Historical assumption: LWR SNF plutonium or highenriched uranium required for FR startup New technology and changing requirements may allow FR startup on low-enriched uranium 8

9 Once-through Fuel Cycle Traditional Fuel Cycles Mining & Milling Uranium Enrichment and Fuel Production Light Water Thermal Reactor Interim SNF Storage 1970s Future LWR-Fast Reactor (FR) Fuel Cycle Waste Disposal Mining & Milling Uranium Enrichment & Fuel Production Light Water Thermal Reactor Interim SNF Storage Spent Fuel Reprocessing Waste Disposal Startup FR on Plutonium from LWR SNF Fast Reactor Natural Uranium, Depleted Uranium. Fuel or Thorium Fabrication 9

10 Alternative Future: Low-Enriched Uranium Startup of Fast Reactors Mining & Milling Enrich Uranium and Fuel Production Low-Enriched Uranium To Start Up Fast Reactor Fast Reactor Interim Storage Spent Fuel Reprocessing Waste Disposal Technical advances may allow fast reactor startup on low-enriched uranium Less expensive than LWR Pu Decouples LWR and future fast reactor fuel cycles: LWR SNF a Waste? Fuel Fabrication Natural Uranium, Depleted Uranium. or Thorium 10

11 Fast Reactor Startup on Low-Enriched Uranium Lowers Uranium Demand LWR lifetimes ~60 y Assumptions U.S. Uranium demand 2.5% Growth rate Fast reactor (FR): Conversion ratio = 1 Four cases LWR Once through FR with startup on LWR TRU FR with startup on 19% 235 U FR with startup on 14% 235 U 11 Low-enriched uranium startup of FRs avoids FR startup constraint of limited plutonium resources from LWR SNF

12 Waste Management: Geological Disposal is Needed For any Choice Develop geological disposal, with a public process Integrate waste management with fuel cycle design Develop risk-informed waste management system: composition not source defines management strategy 12

13 Worldwide Experience in Siting and Operating Geological Repositories Multiple chemical waste repositories built and are operating in Europe The U.S. has operated the Waste Isolation Pilot Plant for transuranic wastes for a decade SNF and HLW repositories Many failures YM has an uncertain future Some siting successes: Finland and Sweden Require Program With Characteristics of Successful Programs Germany: Herfa Neurode Repository Opened in 1975 Chemical Wastes: 200,000 tons/y 13

14 There are Incentives to Couple Fuel Cycles and Waste Management For historical reasons, fuel cycles and waste management have been considered separately Examples of coupling fuel cycles and repositories Traditional separate facilities Repository with retrievability of LWR SNF (maintain options) Collocation and integration of reprocessing, fabrication, and repository Multi-geological waste isolation system Preferred option or options unknown 14

15 Example: Two Ways To Couple Closed Fuel Cycles and Waste Management (WM) Hanford (Washington State) LaHague (France) On-site waste disposal but created a mess MTU/y Low-burnup defense SNF Courtesy of COGEMA Off-site waste disposal 2 x 800 MTU/y Commercial SNF What if Hanford Model With Proper WM? 15

16 Potential Implications of Collocated Integrated Reprocessing Repository Facility Reduces waste volume constraints (No transportation requirement that drives need to minimize volumes) Reduce costs with simplified processing Eliminate long-term repository safeguards with termination of safeguards by low-fissile concentrations in the waste Improve repository performance with waste forms designed for specific geology Assist repository siting by coupling repository to large future back-end facilities (jobs and tax revenue) Repository: Hundreds of jobs Reprocessing: Thousands of jobs Greater equity benefits and liabilities collocated 16

17 Long-term Sustainable Fuel Cycles: a Key Technical Point: CR=1 Sustainable and Has Advantages Conversion ratio: Fissile fuel produced/fuel consumed Advanced reactors make plutonium faster than consume plutonium Historical advanced reactor strategies based on uranium resource expectations and available technologies High conversion ratio desired: CR>1.2 Traditional sodium-cooled fast reactor preferred Plutonium from LWRs to be used to startup a sustainable fast reactor the Sodium-cooled fast reactor Implications of CR = 1 Low enriched uranium startup of fast reactors Saves uranium and lowers enrichment needs Choice of reactors (not just traditional sodium-cooled fast reactors) several which may be more economic (Hard-spectrum LWR, etc.) 17

18 Modeled Multiple Fuel Cycles for a Century Three nuclear growth rates: 1, 2.5, and 4% per year Three fuel cycle options: Light-water reactor once-through fuel cycle Light-water reactor with recycle of LWR SNF Light-water reactor SNF TRU to fast reactors Fast reactors with three conversion rates (rate of fissile fuel production versus consumption) CR = 0.75 (Actinide burner) CR = 1.0 (Make fuel as fast as consume fuel) CR = 1.23* (Make fuel faster than consume fuel) *Traditional future vision of closed fuel cycle using 1970s assumptions 18

19 Cumulative Demand for Uranium (1M MT) MOX has little effect Fast reactors take decades to cause a real difference Little difference between CR = 1 and CR = 1.23 in this century Fuel Cycle By 2050 By 2100 Once-Through LWR MOX LWR LWR-Fast Reactor: CR = LWR-Fast Reactor CR = LWR-Fast Reactor CR = % Growth Rate 19

20 Nonproliferation and the Fuel Cycle: Principally Institutional The U.S. and other nuclear supplier group countries should actively pursue fuel leasing options for countries with small nuclear programs,.,spent fuel take back within the supplier s domestic framework for managing spend fuel 20

21 Closing Observations: 1970s Understandings Uranium is scarce therefore immediate need for closed fuel cycle and fast reactor with high conversion ratio SFR is preferred option with high conversion ratio Fuel cycle contains separate reprocessing, fabrication, and waste management facilities Each country has a full fuel cycle 21

22 Closing Observations: 2010 Understandings Large uranium resources not control reactor choice Priority should be a more economic reactor LWRs will be important for the entire century Traditional SFR not cost competitive relative to LWRs Potentially more competitive options on horizon with CR = 1 New technologies enable fast reactor startup on low-enriched uranium lower cost than plutonium from LWR SNF Unclear if LWR SNF is a waste or resource Large incentives to integrate and collocate reprocessing and repository facilities 22

23 Conclusions LWR with once-through fuel cycle for the next several decades There is a much wider choice of fuel cycle options than historically considered not clear yet which options are preferred Technology is creating new options Fuel cycles must be judged on multiple criteria: economics, safety and security, waste management, environment, resource utilization, and nonproliferation Need for focused effort to assess wider option space, narrow to a few select options, and go forward 23

24 Questions 24

25 Biography: Charles Forsberg Dr. Charles Forsberg is the Executive Director of the Massachusetts Institute of Technology Nuclear Fuel Cycle Study. Before joining MIT, he was a Corporate Fellow at Oak Ridge National Laboratory. He is a Fellow of the American Nuclear Society, a Fellow of the American Association for the Advancement of Science, and recipient of the 2005 Robert E. Wilson Award from the American Institute of Chemical Engineers for outstanding chemical engineering contributions to nuclear energy, including his work in waste management, hydrogen production and nuclear-renewable energy futures. He received the American Nuclear Society special award for innovative nuclear reactor design. Dr. Forsberg earned his bachelor's degree in chemical engineering from the University of Minnesota and his doctorate in Nuclear Engineering from MIT. He has been awarded 11 patents and has published over 200 papers including multiple papers on design options for repositories and alternative geochemical methods to reduce radionuclide releases from repositories. 25