The organic Rankine cycle (ORC) is a Rankine cycle that employs an organic fluid as working medium to generate power from lower temperature sources such as biomass combustion, industrial waste heat, and geothermal heat [1–5].

Most organic Rankine cycle plants produce net power outputs from 1 kW up to several tens of kW, mainly using microturbines and plate heat exchangers.

The efficiency of current high temperature Organic Rankine Cycles does not exceed 24%. Typical steam Rankine cycles show a thermal efficiency higher than 30%, but with a more complex cycle design (in terms of number of components or size).

ORC technologies operate by transferring heat from the source through an evaporator to boil a fluid and create vapor that is expanded across a turbine or other work extraction device. This creates shaft power that can be easily turned into electrical power through a generator.