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DOE Space Nuclear Power and Propulsion (SNPP) Activities DOE Space Nuclear Power and Propulsion Tracey Bishop, Deputy Assistant Secretary Office of Nuclear Infrastructure Programs (SNPP) Activities Office of Nuclear Energy March 10, 2021 U.S. Department of Energy History of DOE Space Nuclear Power and Propulsion Over the past 60 years, DOE has been instrumental in designing, developing and deploying space nuclear power and propulsion systems for the United States space initiatives Navy Transit Program w ith SNA P-3B (1961) SNA P-3 Radioisotope Pioneer 10 SNAP-19 (1972) Thermoelectric Generator Demonstration (1959) Ulysses GPHS-RTG (1990) MSL MMRTG (2011) NERVA Engine Reactor Program (1964-1969) Voyager MHW-RTG (1977) Mars 2020 MMRTG (2020) SNA P-27 Apollo 12 New Horizons GPHS-RTG (1969) (2006) SNA P-10A Reactor Nimbus III (1969) (Launched 1965) Galileo GPHS-RTG (1989) 2 energy.gov/ne DOE’s Role in U.S. Nuclear Space Power • Serves as technical design authority for Space Nuclear Power and Propulsion (SNPP) systems – Radioisotope Power Systems (RPS) – Nuclear Fission Power Systems • Enables through our national laboratory complex research and development in a wide array of technical areas required to advance SNPP technologies • Extends nuclear safety and business frameworks to other agencies to conduct SNPP activities DOE has a long-standing partnership with multiple agencies on space nuclear power and trusted relationships with our national laboratories 3 energy.gov/ne Radioisotope Power Systems (RPS) • Enables and enhances missions by providing electrical power to explore remote and challenging environments where solar power is unavailable – Spacecraft operation – Instrumentation • Converts heat from a radioisotope into electricity – Heat is the product of the natural General Purpose isotope decay process Heat Source • Plutonium (Pu)-238 is the isotope of choice due to its long half-life and high- Pu-238 Fuel energy alpha particle Pellet (Uncladded) Fueled Clad 4 energy.gov/ne Historical Radioisotope Power Systems SNAP-27 SNAP-19 Multi-Hundred Watt GPHS • ~70 We • ~40-45 We • ~150We • ~300We • 1969-1972 • 1970s • 1970s • 1980s-2000s • Apollo 12, 14, 15, • Viking 1 & 2, • Voyager 1 & 2 • Galileo, Ulysses, 16, & 17 Pioneer 10 & 11 Cassini, New Horizons 5 energy.gov/ne Current and Future RPS Technologies • Flight-certified technologies – Multi-mission Radioisotope Thermoelectric Generator (MMRTG) – General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHS-RTG) (Mod 0) – Radioisotope Heater Units • Technology Development Activities MMRTG – Next Generation Radioisotope Thermoelectric Generator, focused on GPHS-RTG (Mod 1) – Dynamic RPS GPHS-RTG Mod 0 Dynamic RPS Next Gen RTG 6 energy.gov/ne Radioisotope Power System Production Fuel Clad Component Heat Source Assembly, Pu-238 Isotope Manufacturing and RTG Fueling and Launch Support Production Encapsulation Testing • Oak Ridge • Oak Ridge • Idaho National •Kennedy Space National National Center Laboratory Laboratory Laboratory •Idaho National • Idaho • Los Alamos Laboratory National National Laboratory Laboratory 7 energy.gov/ne RPS Constant Rate Production • Leveraged DOE’s isotope campaign model with a proven track record to produce radioisotopes – Successfully re-established domestic production of Pu-238 with about 0.9 kg of heat-source oxide produced to date with an average production goal of 1.5 kg/year by 2026 – Increased number of isotope production campaigns and expanded production from one to two DOE research reactors – Accelerated automated target fabrication, equipment modernization, and material handling capabilities across DOE • Stabilized fuel manufacturing with predictable schedule – Demonstrated production rate of 10-15 fueled clads/year to meet customer needs – Integration and cost-sharing opportunities with national security customers to modernize equipment for increased production and worker safety – Modeling of isotope production and fuel manufacturing to support mission planning scenarios 8 energy.gov/ne Nuclear Fission Power Systems • Utilize fission reactions to generate power for space applications – US successfully launched space reactor (SNAP-10A) in 1960s and operated for ~50 days – Nuclear propulsion research and demonstration programs established in 1960s KIWI Test Facility – Modest efforts since the 1960s to evaluate designs • Natural synergy with DOE missions supporting commercial nuclear power industry SNAP-10A – Fuel qualification and development – Design and demonstration of Small Modular and Micro-Reactors – Modeling and simulation capabilities SP-100 NERVA Program 9 energy.gov/ne Current Nuclear Fission Power Technology Development • Fission Surface Power – Demonstrate sustainable power source on lunar surface by 2028 – Minimum power output of 10 kWe for one year, extensible to 40 kWe • Nuclear Thermal Propulsion – Establish technical foundations and Surface Fission Power capabilities to obtain ~ 900-1300s Isp Reactor Concept – Experimental programs underway for fuel development TREAT Fuel • Common fuel development for terrestrial Experiment and space use, including a coated particle fuel Nuclear Thermal Propulsion Concept 10 energy.gov/ne DOE Capabilities • Fuel and materials research, development and qualification critical for any nuclear technology endeavor to demonstrate performance and Advanced Test safety Reactor - Idaho • DOE has invested heavily in capabilities to support commercial nuclear industry – Irradiation capabilities – Post-irradiation examination tools – Fuel supplies – Modeling and simulation – Demonstration • Options to leverage existing user facilities to enhance technical collaborations between the agencies, industry, and universities Transient Reactor High Flux Isotope Test Facility - Reactor –Oak Ridge Idaho 11 energy.gov/ne Nuclear Safety Framework • DOE leverages its nuclear safety framework to support research and demonstration of SNPP technologies • US Space Policy, such as the National Security Presidential Memorandum (NSPM-20), aligns with DOE nuclear safety model to provide transparency for safety reviews – Establishes risk informed approval levels for nuclear launches – Establishes nuclear safety guidelines for government launches – Reduces regulatory burden and supports future commercialization goals by setting expectations rooted in existing US commercial nuclear policy Mars 2020 Launch 12 energy.gov/ne DOE-NASA Partnership Model Agencies utilize a structured framework for nuclear activities to leverage DOE self-regulation and indemnification authorities NASA-DOE Memorandum of Understanding Strategic (10yr.) (October 2016) Interagency Interagency Agreement - Agreement – Nuclear Radioisotope Power Fission Power Program (5yr.) S yste m s Systems (January (October 2018) 2020) Constant Rate Nuclear Thermal Surface Fission RPS Technologies Dragonfly Mission Production Propulsion Power (Multiple) (TBD – FY 2021) Project (1yr.) (November 2018) (April 2020) (TBD-2020) Strategic Partnership Plans (Multiple DOE laboratories/plants) 13 energy.gov/ne Summary • DOE is a key partner on SNPP activities within the US government with a long-proven track record • Recent interagency and industry collaborations enable future progress to develop SNPP technologies to support US space goals • Opportunities for collaboration with US agencies and commercial nuclear power research, development and deployment initiatives to reduce risks and build the domestic nuclear industry 14 energy.gov/ne.
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