Light Water Reactors
Small light water reactors are designed to capitalize on the benefits of North American modular construction, ease of transportation and reduced financing, making them a good option for areas where large nuclear reactors are not needed. These designs typically are smaller than 300 megawatts electric and could replace older fossil-fired power stations of similar size. Designs under development include:
Babcock & Wilcox Co. mPower Reactor
The mPower reactor design is a 180-megawatt electric advanced light water reactor design that uses natural phenomena such as gravity, convection and conduction to cool the reactor in an emergency with a below-ground containment.
Holtec Inherently Safe Modular Underground Reactor (HI-SMUR) 160
The HI-SMUR 160 is a 160-megawatt reactor with an underground core. That feature, Holtec says, means there is no need for a reactor coolant pump or off-site power to cool the reactor core.
NuScale Power Module
The NuScale Power Module is a new kind of nuclear power plant – a smaller, scalable version of pressurized water reactor technology with natural safety features which enable it to safely shut down and self-cool, with no operator action, no AC or DC power, and no external water. Each NuScale Power Module is 45 MW and has a fully integrated, factory-built containment and reactor pressure vessel.
The Westinghouse SMR
The Westinghouse SMR is a 200-megawatt integral pressurized water reactor with all primary components located inside the reactor vessel. It is based on the AP1000 reactor design, which is being built in many new nuclear plants around the world.
High-Temperature Gas-Cooled Reactors
High-temperature gas-cooled reactors could be used for electricity generation, but they would be especially well-suited to providing process heat for industrial purposes, including hydrogen production. These reactors also could be used in the development of tar sands, oil shale and coal-to-liquids applications. The small nuclear reactors would reduce the life-cycle carbon footprint of all these activities. Designs under development include:
General Atomics Gas Turbine Modular Helium Reactor (GT-MHR)
The GT-MHR is a high-temperature reactor with advanced gas turbine technology
Pebble Bed Modular Reactor Ltd. (PBMR)
The PBMR is a high-temperature reactor that uses a gas or steam turbine for power conversion. Substantial design, component testing and fuel development have been undertaken in South Africa.
Liquid Metal and Gas-Cooled Fast Reactors
Liquid metal or gas-cooled fast reactor technologies hold the promise of distributed nuclear applications for electricity, water purification and district heating in remote communities. Fast reactors also could provide sustainable nuclear fuel cycle services, such as breeding new fuel and consuming recycled nuclear waste as fuel, and could support nonproliferation efforts by consuming material from former nuclear weapons, thus eliminating them as a threat. Designs under development include:
GE Hitachi Nuclear Energy Power Reactor Innovative Small Module (PRISM)
The PRISM is an advanced reactor cooled by liquid sodium. As with some other small reactor designs, the plant will be built underground on seismic isolators to dampen the effects of earthquake motion.
General Atomics Energy Multiplier Module (EM2)
The EM2 is a modified version of General Atomics’ high-temperature, helium-cooled reactor. The 240-megawatt reactor is capable of converting used nuclear fuel into electricity and industrial process heat without conventional reprocessing.
Gen4 Energy: The Gen4 Module (G4M)
The reactor, known as the Gen4 Module (G4M), is designed to fill a previously unmet need for a transportable power source that is safe, clean, sustainable and cost-efficient. The reactor has been designed to deliver 70 MW of heat (25 MW of electricity) for a 10-year lifetime, without refueling.
Toshiba 4S (Super-Safe, Small and Simple)
The 4S is a 10-megawatt reactor cooled by liquid sodium for use in remote locations.