Similar to a simple Rankine cycle, a basic organic Rankine cycle (ORC) consists of four processes: increasing pressure of the working fluid through a pump, high temperature heat addition through an evaporator, expansion of the high temperature as well as high pressure fluid through a turbine, and low temperature heat ...

Organic Rankine cycle (ORC) machines are used to convert low-temperature heat resources into power. Examples include systems making use of waste heat in a cogeneration system, low temperature geothermal electricity generation, solar ponds, and potentially OTEC.

An organic Rankine⁵ cycle turbine is a small turbine that is identical in design to a steam turbine but which uses a low boiling point organic fluid as its working fluid instead of water and steam. The turbine is packaged into a closed cycle system with a condenser and heat exchanger.

A basic ORC consists of four main components: an evaporator, an expander, a condenser, and a pump. Figure 1 shows the simplest ORC configuration. As can be seen, liquid in saturated conditions (1) is pumped, increasing its pressure, into the evaporator (2) where it is evaporated by supplying energy in the form of heat.