HTGR Knowledge Base
Topical Article 6: Power Plants
Two designs for Modular HTGR power plants are currently under active development. One of the designs employs pebble fuel (6 cm diameter spheres), and the other prismatic fuel (hexagonal blocks ~35 cm wide by 75 cm high).
Pebble Bed Modular Reactor (PBMR)
The PBMR is under development as a commercial project. The project is advanced by an international design team led by the South African electric utility Eskom. The design comprises a pebble bed core and closed cycle gas turbine with a thermal power of approximately 260 MWt and net electrical output of approximately 110 MWe. An initial single unit prototype is planned followed by commercial offerings for plants of up to 10 modules, which can be incrementally constructed in accordance with generation needs and financial constraints.
Gas Turbine Modular Helium Reactor (GT-MHR)
The GT-MHR is under development as a combined private/public sector project. The project is advanced by an international consortium led by General Atomics in the USA and OKBM in the Russian Federation. The design comprises a prismatic core and closed cycle gas turbine with a thermal power of approximately 600 MWt and net electrical output of approximately 280 MWe. The initial application is intended to be the consumption of plutonium from dismantled weapons in conjunction with the generation of electricity. Future commercial deployment for electricity production using low enriched uranium fuel is anticipated.