The existing modular HTGR design was coupled with helium
gas turbine power conversion system based on Brayton cycle, or
with a steam circuit based on Rankine cycle for electricity generation.
The former was a premature technique not sufficient enough
for commercial use, and the latter could not offer high cycle efficiency
and needs to prevent possible water enters into the core.
As a new approach, the OBMR was partnered with a conventional
natural gas combined cycle (NGCC) for thermal power conversion
(Jeong et al., 2005). The NGCC power conversion plants are existing
available technology and most efficient amongst all commercial
power plants.