NUCLEAR ENERGY: RISKS AND BENEFITS

Transcription

1 NUCLEAR ENERGY: RISKS AND BENEFITS Dan Gabriel Cacuci Conference Europe, Italy, Piedmont: Energy as a Development Driver Torino, 04 February 2011

2 Europe s Energy Challenges (EU SET-Plan 2008) 1. Security of Supply 2. Reduction of Greenhouse Gas Emissions 3. Competitiveness Nuclear Energy: Risks and Benefits Benefits Risks Energy-Independence Long-Term Security Economically Feasible No Greenhouse Gases High Capital-Investments Low-Dose Irradiation/Contamination Effects? Severe Accidents (very low probability) Ultimate Disposal of High-Level Waste Proliferation of Nuclear Weapons

3 Challenge 1: security of supply Main EU imports from politically stable countries (Canada, Australia); Easy to build strategic stockpiles; For Gen-IV, optimized use of resources sustainability Generation IV Roadmap

4 Challenge 2: reduction of Greenhouse Gas Emissions Cannot achieve Europe s objectives of CO2 reductions without nuclear

5 Challenge 3: Competitiveness, electricity generation costs [ ] Nuclear energy is economically competitive.

6 Spent Fuel Radiotoxicity Spent Fuel 10 8 Sv/t 6 Radiotoxicity 5 4 Other U 3 2 Pu Reusable Materials Waste U: % Other Pu: 1 % FP: 3-5 % 1 FP Time (Years) 1 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0,1 Contributions to Radiotoxicity Other FP Pu Am Np Time (Years) U

7 Responsible Management of Spent Fuel Proven advantages of recycling Ultimate Wasre Disposal Mines Natural Uranium Uranium recyclable Plutonium Recycling : MOX Fuel fabrication Chemistry Enrichment Enriched Uranium Fuel fabrication Recycle 96% of spent fuel Save 30% of natural resources Represents less than 6% of total kwh-price Reduces by factor 5 the volume of waste Reduces by factor 10 the radiotoxicity of waste Current technologies guarantee long-term (tens of thousands of years) confinement and stability Spent Fuel Reprocessing Reactors & Services Front-End Sector Reactors & Services Sector Back-End Sector Recycling buys time for exploring all possibilities to optimize sustainable waste management strategies

8 Generation-IV Reactors: Closed Fuel Cycle Integral re-use of non- separated Actinides Drastic Time-Reduction of Radiotoxicity Relative Radiotoxicity Spent Fuel (Pu + MA + SP) 1 0,1 Natural Uranium SP MA + SP Time (Years) R&D for new isotope separation processes

9 Vitrification of High-Level Radioactive Waste 1 % Volume > 90 % of Radiotoxicity Over Packages fabricated so far in La Hague Vitrified HLR Waste-Package

10 Reprocessing Plant La HAGUE (AREVA, France)

11 La Hague: Interim Storage of HLR Waste-Packages

12 Underground Waste-Disposal Laboratory in Bure (France)

13 Underground Waste-Disposal Laboratory in Bure

14 Development of renewable energies Valorization of biomass (particularly bio-fuels from wood) Bure-Saudron Laboratory

15 EXAMPLE: Gen-I vs. Gen-II Biofuels (Potential) in France: 50 MToe Current Consumption (Transport) 2 nd Gen. Allo-thermal? LIMIT: Competition with food LIMIT of the auto-thermal thermo-chemical (or enzymatic) routes Competition with other uses of wood or vegetal materials 1 st Generation 2 nd Gen. Auto-thermal 2 nd Gen. Allo-thermal External input electricity (NUCLEAR) 2 nd Gen. Allo-thermal External input electricity (NUCLEAR) + H2 (NUCLEAR) External input electricity (NUCLEAR) + H2 (NUCLEAR) + Use of domestic and municipal waste 25 MToe 15 MToe 7 MToe 4 MToe Goal 2030 Goal 2015 Goal 2008

16 R & D in Support of Current LWRs Life-time Extension, Improved Reliability Cost reduction Improved Fuels (MOX, Higher Burnup ) Environmental impact reduction

17 CASL: The Consortium for Advanced Simulation of LWRs A DOE Energy Innovation Hub for Modeling and Simulation of Nuclear Reactors ( or info@casl.gov) US President Obama ( ): At ORNL, they re using supercomputers to get a lot more power out of our nuclear facilities.

18 CASL interface with M&S R&D Programs OBJECTIVE 1: Develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of current reactors PoR-1 (2010) MPO LWRS Materials and Aging: collaborative agreement to address pressure vessel and internals materials characterization studies. OBJECTIVE 2: Develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration's energy security and climate change goals OBJECTIVE 3: Develop sustainable nuclear fuel cycles OBJECTIVE 4: Understand and minimize the risks of nuclear proliferation and terrorism MPO/VRI NEAMS: Draft plan to establish a common fuel properties data structure VUQ LWRS & NEAMS: Draft plan to establish a common set of benchmark problems and validated experimental data files. CASL SLT: Determine degree of collaboration on modeling and simulation development on certain programs of mutual benefit, e.g., Exascale Co-Design

19 The Vision for Future Nuclear Energy

20 Generation IV Int. Forum (GIF): Goals Nuclear Systems for Sustainable Energy Development Technological Maturity: ca Progress (beyond Gen III) Economically competitive Safe and Reliable Waste minimization Resource maximization Non-proliferation and Safeguards E.U. Chartered July 2001 Additional Applications Electricity, Hydrogen Production, Desalinization, Process heat

21 Worldwide plans USA Power Plants by 2020 including nuclear (> 50 GWe) FINLAND 5 th reactor (+1 EPR?) FRANCE +2 EPR ITALY KOREA nuclear capacity increase + 9 GWe by ~ 2015 UKRAINE +11 Reactors by 2030 CHINA nuclear capacity increase > 30 GWe by 2020 JAPAN nuclear capacity increase + 21 GWe by % Coal Oil Gas Nuclear R en Hydro INDIA nuclear capacity increase from 2.5 to 20 GWe by % 20% 0% Source : TotalFinaElf

22 7 points about Nuclear Energy (NE): NE is part of the solution (not the problem!) for meeting the increasing national & international need for electricity; NE is needed to attain CO2 savings; NE guarantees economical, safe & reliable electrical energy, particularly for base-load; NE and renewable energies are synergetic, not competing! Germany uses now NE to compensate time-varying production from renewables; France plans to use NE-generated electricity & H2 for Gen-II biofuels; NE is internationally increasing, which would be good for Italian industries (new int. markets and home jobs); NE has great potential for technological advances (GEN-IV); NE has *today* technological solutions for safe & economical waste disposal (Sweden, Finland, France, Switzerland, Russia, etc).

23 In the next 50 years. ~ people ~ 15 Gtoe/year consumption I believe all sources of energy will be synergistically needed.

24 RESERVE SLIDES

25 Challenge 2: reduction of Greenhouse Gas Emissions Share in energy consumption in EU-25 in 2004 Nuclear energy = largest source of low Carbon energy in Europe

26 Uranium Enrichment Natural Uranium = 0.7% U % U-238 LWRs need enriched fuel (2,5% - 4,9% U-235) Enrichment Technologies: Gas- Ultracentrifuge or Gaseousdiffusion plants

27 A wide international spectrum of Generation III / III+ Reactors: Generation IV Int. Forum (GIF) List of Near Term Deployment Plants of Generation III /III+ : Advanced PWR: Advanced BWR: AP 600, AP 1000, APR1400, APWR+, EPR ABWR II, ESBWR, HC-BWR, SWR-1000 Advanced Heavy-Water Reactor : ACR-700 (Advanced CANDU Reactor 700) Integrated Small- und Medium- Power Reactors: CAREM, IMR, IRIS, SMART High-Temperature- Gas-Cooled Modular Reactors: GT-MHR, PBMR

28 Energy Scenarios B C ecologically driven growth (1300GWe)

29 Process evaluation and choice (1/2) High temperature processes Thermo dynamical advantages: High temperature and low pressure processes allow optimal moles conversion 8 7 H2 6 5 H 2 /CO CO 4 C solide 3 H 2 2 O 1 CO 2 CH T( C) Kinetic advantages: High temperature( C) help Tar cracking Methane conversion to CO + H2 Ashes fusion (Interesting when using wastes) High pressure processes Final application depending on pressure 30bar =>Gas-shift 20-40bar =>Fischer-Tropsch synthesis ~70bar => Methanol synthesis Less compression stages =>10% reduction of the energetic cost (PCI biomass) Reduction of investment costs and technological constraints for big industrial plants (> 50 MWth) Optimization of gas cleaning process IDEAL FOR PRODUCTION OF CO & O2

30 Process evaluation and choice (2/2) Process of reference 1 for CEA : thermal pre-treatment ( C) + Entrained flow reactor working between 1200 and 1400 C Existing technology for coal gasification : Shell Uhde, Future- Energy, Lurgi, Conoco-Phillips. Limited experience on biomass : CHOREN plants Noell Entrained-Flow Gasifiers Reactor with Cooling Screen Reactor with Cooling Wall Burner insert Burner insert Cooling jacket Process of reference 2 : Fluidised bed ( C)+ high temperature gas reformer ( C) Gas and slag outlet Refractory lining SiC layer Coolant Partial quench system Gas outlet

31 Le procédé allothermique : augmenter le rendement masse C 6 H 9 O H 2 O => 6 CO + 6,5 H2 Réaction de gazéification idéale : une réaction endothermique Autothermique Allothermique (énergie externe) La combustion consomme ~ 2C et 2 H2 Restent: 4 CO + 4,5 H2 Restent 6 CO + 6,5 H2 La synthèse de biocarburant nécessite: H2/CO ~2 Réaction de Gaz-Shift: 1,5 CO => 1,5 H2 Shift 2 CO=> 2 H2 Pas de shift, mais Apport H2 externe Restent: 2,5 CO + 6 H2 4 CO + 8,5 H2 6 CO + 12 H2 Bilan synthèse: max 2,5 -CH2- Bilan avec pertes: ~1,5 (-CH2- ) Rendement masse ~ 15% 4 -CH2- ~3 (-CH2-) Rendt masse ~30 % 6 -CH2- ~ 5 (-CH2-) Rendt masse ~ 48%