Advances in Reactor Concepts: Generation IV Reactors Research Workshop Future Opportunities in Nuclear Power October 16-17, 2014 Purdue University Prof. Won Sik Yang Purdue University Status of Nuclear Power Production Nuclear energy is a significant contributor to U.S. and international electricity production – 15% world, 20% U.S., 74% France 2 Status of Nuclear Power Production Nuclear energy and hydropower are the only two major established base-load low-carbon energy sources. Efforts to reduce CO2 emissions are thus a major factor in the renewed interest in nuclear energy that has become apparent in recent years. Total: 20130 TWh World Electricity Generation (2009) IEA/NEA, Nuclear Energy Technology Roadmap (2010) 3 Future Use of Nuclear Energy Extended lifetime and optimized operation of existing plants Construction of new plants (evolutionary designs in near term) Closure of fuel cycle to improve waste management – Strengthened international safeguards regime Sustainable generation of electricity, hydrogen and other energy products 4 Generations of Nuclear Reactors 5 Generation IV Systems: Technology Goals Sustainability – Sustainable energy generation through long-term availability of systems and effective fuel utilization – Minimize and manage nuclear waste and reduce the stewardship burden in the future Safety & Reliability – Very low likelihood and degree of reactor core damage – Eliminate the need for offsite emergency response Economics – Life-cycle cost advantage over other energy sources – Level of financial risk comparable to other energy projects Proliferation Resistance & Physical Protection – Unattractive materials diversion pathway – Enhanced physical protection against terrorism 6 Overview of Generation IV Systems Neutron Fuel Coolant Power Plant System Spectrum /Fuel Cycle Temp. (C) (MWe) Effici. (%) Applications Sodium Cooled Fast MOX, Metal 500 - 550 50 42 Electricity, Fast Reactor /Closed 300-600 Actinide Recycle (SFR) 1500 Very High Thermal Coated particles 900 -1000 250 > 47 Electricity, Temperature /Open Hydrogen Production, Reactor (VHTR) Process Heat Gas-Cooled Fast Carbides 850 200- 45 - 48 Electricity, Fast /Closed 1200 Hydrogen Production, Reactor (GFR) Actinide Recycle Supercritical Thermal, UOX, MOX 510 - 625 1500 Max. 50 Electricity Water Reactor Fast /Open; Closed (SCWR) Lead-Cooled Fast Nitrides; MOX 480 - 570 50-150 42 - 44 Electricity, Fast Reactor /Closed 300-600 Hydrogen Production (LFR) 1200 Molten Salt Thermal, Fluorides salts 700 - 800 1000 Max. 45 Electricity, Reactor Fast /Closed Hydrogen Production, (MSR) Actinide Recycle A Technology Roadmap for Generation IV Nuclear Energy Systems, December 2002 GIF R&D Outlook for Generation IV Nuclear Energy Systems, August 2009 7 Sodium-Cooled Fast Reactor (SFR) Features fast spectrum and closed fuel cycle – Can either burn actinides or breed fissile material High level of safety can be achieved through inherent and passive means R&D focus ESFR – Analyses and experiments that demonstrate safety approaches – High-burnup, minor actinide bearing fuels – Develop advanced components and energy conversion systems KALIMER JSFR SMFR 8 Designs Being Developed In the US, innovative fast reactor designs are being developed – Advanced burner sodium-cooled fast reactor (ABR) for waste management – Breed and burn nuclear systems for improved fuel utilization – Small modular reactors for near-term deployment in remote locations and other countries China has constructed CEFR, which achieved the initial criticality on July 21, 2010. Developing CFR-600 with oxide fuel, but will be converted to metallic fuel. In India, the 500 MWe DFBR is expected to be online soon; they plan to construct 4 more 500 MWe units by 2020, and then 1000 MWe plants Russia has constructed a BN-800 reactor, which achieved the initial criticality on June 27, 2014, and is developing the BN-1200 design Japan envisions commercial fast reactors by 2050, and plans to construct a demo plant by 2025 (JSFR) France envisions commercial fast reactors by ~2045, and plans a demo plant by 2020 (ASTRID) Korea is developing the 150 MWe PGSFR design for demonstrating TRU transmutation 9 Very High Temperature Reactor (VHTR) High temperature, helium cooled, graphite moderated reactor – High temperature enables non-electric applications Goal – reach 1000 °C, with near term focus on 700 - 950 °C Reference configurations are the prismatic and the pebble bed 10 Very High Temperature Reactor (VHTR) R&D focus on materials and fuels HTR-PM – Shared irradiation • Confirmed excellent performance of UO2 TRISO fuel – Develop a worldwide material handbook – Benchmarking of computer codes Japanese HTTR (30 MWt) is in operation – 50 days continuous operation at 950 °C completed March 2010 Chinese HTR-PM demonstration plant is under construction – Pebble bed core, 750 °C outlet temperature, steam cycle, 40% efficiency – Two 250 MWt NSSS modules for 210 MWe electricity – First concrete poured in Dec. 2012 – Plant operation expected around end of 2017 11 Gas-Cooled Fast Reactor (GFR) High temperature, helium cooled fast reactor with closed fuel cycle – Fast spectrum enables efficient use of uranium resources and waste minimization – High temperature enables non- electric applications – Non-reactive coolant eliminates material corrosion Very advanced system – Requires advanced materials and fuels Key R&D focus Decay heat removal (LOCA) is a challenge – SiC clad carbide fuel – High power density – High temperature components – Low thermal inertia and materials 12 Supercritical-Water-Cooled Reactor (SCWR) 30 Merges Gen-III+ reactor technology with compressible liquid supercritical fluid 25 advanced supercritical water technology SCWR used in coal plants 20 liquid PWR 15 Operates above the thermodynamic superheated vapor Pressure (MPa) Pressure 10 critical point (374 °C, 22.1 MPa) of water BWR vapor Fast and thermal spectrum options 5 0 Pressure tube or pressure vessel 250 350 450 550 Temperature (C) options Key R&D focus – Materials, water chemistry, and radiolysis – Thermal-hydraulics and safety to address gaps in SCWR heat transfer and critical flow databases – Fuel qualification 13 Lead-Cooled Fast Reactor (LFR) Lead is not chemically reactive with ELFR air or water – Highly corrosive and erosive Fast spectrum and closed fuel cycle Three design thrusts – European Lead Cooled Fast Reactor (Large, central station) – Russian BREST-OD-300 (Medium size) – US SSTAR (Small transportable system) R&D focus – 1500 MWt / 600 MWe – Materials corrosion – MOX fuel – High burnup, MA-bearing fuels – Coolant temp., 400/480C – Max. clad temp., 550C – Safety – Efficiency: ~42% – Breeding ratio: ~1 14 LFR Concepts Being Studied BREST-OD-300 SSTAR – 700 MWt / 300 MWe – SSTAR is a small natural – UN+PuN fuel circulation fast reactor of 20 – Coolant temp: 420/540C MWe/45 MWt, that can be scaled up to 180 MWe/400 MWt. – Max. cladding temp., 650C – Uranium nitride fuel with 15-20 – Efficiency: 42% year lifetime – Breeding ratio: ~1 15 Molten Salt Reactor (MSR) High temperature system Design options – Fuel dissolved in molten salt coolant • Traditional MSF concept • On-line waste management – Solid fuel with molten salt coolant • VHTR + molten salt coolant Key R&D focus – Neutronics – Materials and components – Safety and safety systems MSFR – Since 2005, European R&D interest – Liquid salt chemistry and properties has focused on Molten Salt Fast – Salt processing neutron Reactor (MSFR) as a long term alternative to solid fueled fast neutrons reactors 16 MSR Concepts Studied Two reactors concepts using molten salt are studied in the GIF MSR – Molten salt reactors, in which the salt is both the fuel and the coolant • France and Euratom work on MSFR • Russia works on MOSART (Molten Salt Actinide Recycler & Transmuter) – Reactors with solid fuel cooled by molten salt • USA and China work on FHR (fluoride salt-cooled |high-temperature reactor) concepts 17 Summary Generation-IV systems are being developed worldwide – Gen-IV International Forum was established in 2001 and provides an international framework for development of Gen-IV systems – Collaborative projects started with significant R&D investment worldwide – Prototype demonstration reactors are being designed and/or built • SFR (France and Russia) • VHTR (China) Much still needs to be done before Gen-IV systems become a reality – Continue R&D on Gen-IV systems – Develop advanced research facilities – Engage industry on the design of Gen-IV systems – Develop the workforce for the future 18 .