The ORC is a thermodynamic cycle that converts low-grade heat, such as waste heat from boilers, furnaces, engines, or solar collectors, into useful mechanical work or electricity.

The organic working fluid has a lower boiling point and higher vapor pressure than water and is therefore able to use low-medium temperature heat sources to produce electricity more efficiently than steam cycle.

The Brayton cycle, also known as the Joule cycle, is a thermodynamic cycle that describes the operation of certain heat engines that have air or some other gas as their working fluid.

A recuperator is a type of heat exchanger that has separate flow paths for each fluid throughout its passages and heat is transferred through the separating walls. Most recuperators operate as counter-flow heat exchangers. Only the first level of the GPP discussed here uses a recuperator.