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Nano and New Materials for Advanced Nuclear Energy Applications John E. Marra, Ph.D. Associate Laboratory Director Savannah River National Laboratory 2010 Ohio Innovation Summit Columbus, OH – April 20-21, 2010 Disclaimer
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Nano and New Materials for Advanced Nuclear Energy Applications John E. Marra, Ph.D. Associate Laboratory Director Savannah River National Laboratory 2010 Ohio Innovation Summit Columbus, OH – April 20-21, 2010
Disclaimer • The views and opinions presented are those of the authors and do not represent the official position of the US Department of Energy or Savannah River Nuclear Solutions, LLC.
Global Demand Doubles by 2030 [Source – United States Department of Energy, Energy Information Administration, “International Energy Outlook 2009,” DOE/EIA-0484 (May 2009), see http://www.eia.doe.gov/oiaf/ieo/index.html]
We are talking about powering the planet with a carbon-free energy source Our Ambition is Commensurate with the Challenges of the Times Pollution plume over Asia 4
The Nuclear Renaissance Must Provide Integrated Solutions that … Add MWe on the grid Economically attractive reactor power systems Economically attractive nuclear cogeneration and process heat systems In a way that addresses the traditional ‘barriers’ to nuclear energy implementation Safety (or perception thereof) Capital cost Proliferation Waste Management (i.e., sustainable fuel cycles)
Nuclear Energy in the Obama Administration • ‘But to create more of these clean energy jobs, we need more production, more efficiency, more incentives. And that means building a new generation of safe, clean nuclear power plants in this country.’ • President Obama from the State of the Union, • January 27, 2010 • ‘President Obama and I are committed to restarting the nuclear industry in the United States.’ • Secretary Chu at the American Nuclear Society Meeting, • November 16, 2009
US DOE Nuclear Energy Program • Greater Energy Security in a Safer, Cleaner World • Imperatives in advancing nuclear energy • Extend life of existing fleet • Enable new builds • Transform the industrial and transportation sectors • Develop sustainable fuel cycles • Manage proliferation risk A science-based, results-oriented R&D program
Open/Once-Through Electricity, process heat Reactor Geologic disposal of used fuel Fuel Ore recovery, refining and enrichment Electricity, process heat Modified Open Geologic disposal of spent fuel Reactor Geologic disposal of process waste Fuel Ore recovery, refining and enrichment Fuel treatment Fully Closed (Full Recycle) Electricity, process heat Reactor Geologic disposal of process waste Fuel Ore recovery, refining and enrichment Separation A New Framework • No recycling or conditioning of used fuel • Low uranium utilization • Limited used fuel conditioning or processing • High uranium utilization and burn-up (used fuel is spent fuel) • Multiple reprocessing steps and transmutation of actinides • ‘Complete’ uranium utilization
Materials Advancements • Materials critical throughout nuclear fuel cycle • From fuel/target processing to waste remediation & immobilization to close the fuel cycle • Materials capable of incorporating a variety of radionuclides • Ceramic- and glass-based waste forms are durable and can be economically produced • Next-generation nuclear facilities will require high-performing materials • Reduce capital costs, improve operating parameters, etc.
Advanced Materials are Key Enablers • Major Areas of Application • Nuclear Power • Fuel, target, and cladding materials • Reactor vessels & components • Fuel Cycle Closure • Reprocessing operations • Waste forms • Glass • Ceramics • Cement • Alloys • Geologic disposal
Nuclear Energy Imperatives (1) Extend life, improve performance, and sustain health and safety of current fleet – THE bridge to a low-carbon future Extend life beyond 60 years Enable power up-rates Manage SNF inventories 110 100 90 80 70 60 Number of Reactors or Electricity Production 50 (MW-years) 40 30 20 10 0 1965 1975 1985 1995 2005 Years
Challenges Facing the Current Fleet • The aging fleet has issues in the following areas: • Aging and degradation of passive components • Reactor pressure vessel, concrete, buried pipes, cables etc. • Industry is driving the fleet harder through power up-rates. • Fuel reliability and performance issues • Fuel burn-up has limited room to increase in context of current materials performance. • The instrumentation and control systems rely on obsolete analog technologies • Design and safety analysis tools were built in 1980’s • Plant-aging effects were not taken into considerations. • Existing tools have low fidelity and limited capabilities. • Waste legacy is the most critical issue for nuclear energy in terms of public perception and acceptance.
Fuel, Target, and Cladding Materials • Nuclear fuels generate power from heat produced from nuclear fission and radioactive decay • Ceramics are baseline technology • High melting temperatures • Chemical compatibility • Resistant to corrosion • Easily fabricated by conventional cold pressing and sintering techniques • Advanced cladding materials (nano-derived alloys or ceramics) to allow ‘deeper burn,’ higher temperatures, etc. increased efficiency
Advanced Fuel Materials • Next generation reactor systems are utilizing advanced non-oxide ceramic materials • Carbides and nitrides have had extensive application in conventional reactor systems • Inert Matrix Fuels (IMFs) being designed to burn excess Pu in conventional reactor systems • Fabrication is difficult using conventional processing methods
Advanced Materials and Supporting Data Are Required For Transmutation Fuels to Reach High Burn-up The effects of fast flux neutron irradiation on the properties of core reactor materials under prototypical conditions of irradiation temperature and flux are key needs Near-term needs: Withstand a fluence up to 200 dpa to achieve ~20% burn-up Irradiation Temperature 360-625ºC Traditional Materials: F/M steels such T91, HT-9 and 316L Longer term Go to greater than 20% burn-up (greater than 200 dpa) Increase temperature (greater than 625ºC) Requires advanced materials ODS strengthened F/M steels –MA-957, 14YWT, 12YWT New Materials?
Nuclear Energy Imperatives (2) Improve affordability of nuclear power – enable new builds Provide loan guarantees Partner with NRC to develop confirmatory analysis capabilities for advanced reactors to support NRC design certification, plant licensing, and operating regulatory oversight Develop affordable LWR SMR (Gen-IV) power systems Reduce incremental cost of nuclear capacity additions Develop “Transitional LWR” (Gen-IV) power systems 100+ yr license ~25% reduction in capital cost per kW and operating cost Significantly lower SNF volume and SNF actinide content Blank-sheet-of-paper assimilation of lessons-learned, modern materials, and innovative NSSS and BOP system architectures
Construction Materials for Current Reactor Designs Despite considerable differences in operating parameters, there are common material uses between LWR and SFR applications
Improved Materials May Allow Improved Performance • Several key requirements drive development • Economy: reactor technology must be economically competitive • Flexibility: A number of different missions may be required (power generation, process heat, isotope burning. • Safety: Both inherent safety features and defense in depth will be required. • Choosing the right materials can impact all three factors. • Economy: reduce capital costs through reduced commodities and simplifications • Flexibility: higher material performance allows greater options to designers • Safety: higher material performance promotes larger safety margins and more stable performance over longer lives
Nuclear Energy Imperatives (4) – Sustainable Fuel Cycles Manage and disposition the LWR SNF we have Challenge the assumption that nuclear energy = 100,000+ year waste problem Develop fuels, reactors, and fuel cycles that produce lessSNF and lower long-lived actinide concentrations in SNF Develop reactors that transmute the SNF / actinide waste we have and that we will produce Improve fuel cycle economics The principal obstacle to closing the fuel cycle Address front-end and back-end Integrate uranium management and re-use
Recycling Can Greatly Reduce Long-term Radiotoxicity of Nuclear Waste … But is not the Only Consideration Relative Radiotoxicity Pu, U, & MA Removed Used Fuel ~300,000 Years ~300 Years ~10,000 Years Natural Uranium Ore U & Pu Removed Time (years) LWR Fuel 50 GWd/MT, 5 Years Cooling
Addressing Legacy & Newly Generated Wastes • Metals, ceramics, glasses, glass-ceramics, and cements are key materials for closure of the fuel cycle • Manufacturing processes are straightforward and simple with equipment well-suited for remote application • Microstructures capable of incorporating a variety of radionuclides • Final structures are stable and durable – exceeding all performance standards for interim and long-term storage • Behavior can be understood through closely-coupled theory, experimentation, and modeling
Waste Form S&T of Specific Materials • Borosilicate glass and alloys have been widely used to stabilize nuclear wastes • Advanced wasteforms with enhanced properties needed for next-generation applications • Structure and chemistry • Phase transitions as a function of temperature and radiation field • Chemical durability over a range of conditions (thermodynamic and kinetic studies) • Corrosion mechanisms and rates • Mechanical properties • Response to radiation Ability to sequester radionuclides of interest over geologic timescales
Federal Repository • Nuclear Waste Policy Act of 1982 (as amended in 1987) governs the permanent disposal of high-level radioactive waste • Disposed of underground, in a deep geologic repository • Yucca Mountain in Nevada identified by NWPA as potential site • New ‘Blue-Ribbon’ Commission
Conclusions • Nuclear power offers several significant advantages towards reduction of GHG emissions and energy independence • Provides ‘base-load’ power • Cost competitive over the long-term • Reactors can be sized for multiple uses • Grid appropriate • Load following • Addressing key issues of capital cost, waste management, and proliferation will require advances in materials performance
Conclusions • Materials advances play critical role toward achieving goal of nuclear renaissance • Faster, cheaper reactor construction – improved fabrication • Improved in-reactor performance – ‘deep burn’ scenarios • Fuel cycle closure • ‘Designer materials’ for separating and sequestering radionuclides – targeted toward long-life
Summary and Conclusions • The world is faced with a set of challenges related to energy supply, and global climate change • Nuclear power provides a sustainable energy source • Nuclear power is a ‘cradle-to-cradle’ technology • Nuclear renaissance requires resolution of critical issues associated with safety, cost, waste management, and proliferation • Is this the ‘last, best chance?’