A fuel cell system and process using an organic Rankine cycle to produce shaft
work to operate a fuel cell system component such as an air compressor. The air
compressor delivers compressed air to a fuel cell stack. The steps of the Rankine
cycle include pumping a liquid working fluid to an elevated pressure, heating the
fluid to a gas, expanding the high temperature and high-pressure gas through an
expander to produce shaft work used to drive a fuel cell system component such
as an air compressor, and then removing energy from the cooling fluid to change
the gas back to a liquid, and repeating the cycle. The liquid fluid can be heated
by an external boiler, or one of the components of the fuel cell system such as
the combustor and/or the fuel cell stack.
