Micro integral nuclear reactor

A nuclear power system comprising:

• a micro integral nuclear reactor including:
• a reactor core including a plurality of fuel assemblies, each fuel assembly comprising a plurality of fuel elements, the plurality of fuel assemblies defining core primary coolant flow passages through the reactor core, the reactor core being structured such that, when operating, a primary coolant flows through the core primary coolant flow passages and absorbs heat generated by nuclear fission within the reactor core, each fuel element containing uranium-235 (U-235), and the fuel of the reactor core being enriched to a concentration of 5 percent or greater and less than 20 percent U-235 by weight of uranium within the reactor core;
• a steam generator fluidly connected to the core primary coolant flow passages to receive the primary coolant and, when operating, transfer heat from the primary coolant to a secondary coolant to generate steam;
• a primary coolant circuit fluidly coupling the core primary coolant flow passages and the steam generator such that, when operating, the primary coolant circulates between the reactor core and the steam generator;
• and
• a reactor pressure vessel housing the reactor core, the steam generator, and the primary coolant circuit;
• a turbine-generator assembly fluidly coupled to the steam generator to receive the steam and, when operating, generate electrical power and discharge exhaust;
• a condenser fluidly coupled to the turbine-generator assembly to condense the exhaust into condensed secondary coolant;
• and
• a secondary-coolant circuit fluidly coupling the steam generator, the turbine-generator assembly, and the condenser such that, when operating, the condensed secondary coolant is returned from the condenser to the steam generator to complete a recirculating flow path,
• wherein, when operating, the nuclear power system produces an electrical power output from 2 megawatts-electric (MWe) to 20 MWe.

A micro integral nuclear reactor comprising:

• a reactor core including a plurality of fuel assemblies, each fuel assembly comprising a plurality of fuel elements, the plurality of fuel assemblies defining core primary coolant flow passages through the reactor core, the reactor core being structured such that, when operating, a primary coolant flows through the core primary coolant flow passages and absorbs heat generated by nuclear fission within the reactor core, each fuel element containing uranium-235 (U-235), and the fuel of the reactor core being enriched to a concentration of 5 percent or greater and less than 20 percent U-235 by weight of uranium within the reactor core;
• one or more neutron reflectors surrounding the reactor core, the one or more neutron reflectors being circumferentially disposed around the reactor core;
• a steam generator fluidly connected to the core primary coolant flow passages to receive the primary coolant and, when operating, transfer heat from the primary coolant to a secondary coolant to generate steam;
• a primary coolant loop fluidly coupling the core primary coolant flow passages and the steam generator such that, when operating, the primary coolant circulates between the reactor core and the steam generator, wherein the primary coolant is light water;
• a pressurizer fluidly connected to the primary coolant loop and configured to regulate the pressure of the primary coolant at an operating pressure sufficient to maintain the primary coolant in a liquid state during operation;
• and
• a reactor pressure vessel housing the reactor core, the steam generator, the primary coolant loop, and the pressurizer,
• wherein, when operating, the micro integral nuclear reactor produces a thermal power output from 6 megawatts-thermal (MWt) to 60 MWt.