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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
Haihua Zhao, Per F. Peterson
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 145-157
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3832
Articles are hosted by Taylor and Francis Online.
This paper presents an overview and a few point designs for multiple-reheat Brayton cycle power conversion systems (PCSs) using heat from high-temperature molten salts or liquid metals. All designs are derived from the General Atomics gas turbine-modular helium reactor (GT-MHR) power conversion unit (PCU). Analysis shows that, with relatively small engineering modifications, multiple GT-MHR PCUs can be connected together to create a PCS in the >1000 MW(electric) class. The resulting PCS is quite compact, and results in what is likely the minimum gas duct volume possible for a multiple-reheat system. To realize this, compact plate type liquid-to-gas heat exchangers (power densities from 10 to 120 MW/m3) are needed. Different fluids such as helium, nitrogen and helium mixture, and supercritical CO2 are compared for these multiple-reheat Brayton cycles. For turbine inlet temperatures of 900, 750, and 675°C, the net thermal efficiencies for helium cycles are 56, 51, and 48%, respectively, and corresponding PCU power densities are 560, 490, and 460 kW(electric)/m3, respectively. The very high PCU power densities could imply a large material saving and low construction cost, and bring down the specific PCU cost to about half that of the current GT-MHR PCS design.