HOW DOES AN ORC SYSTEM WORK
GERMAN ENERGY SYSTEMS
ORGANIC RANKINE CYCLE
An ORC system (Organic Rankine Cycle) consists of several components:
The heat from the outside (waste heat from the biogas plant or from other heat sources) is transferred to the hot water circuit via it.
It transfers the heat from the hot water circuit to the ORC circuit. This is a liquid working medium that is under pressure (approx. 17 bar). The working medium evaporates.
Expansion machine (turbine)
The steam from the working medium drives the expander, which is connected to a generator and generates electricity. After evaporation, the working medium is pressureless, but still in vapor form.
Here the working medium is cooled down and liquefied again. The residual heat can still be used, e.g. for drying.
It brings the liquid working medium in the ORC cycle to a pressure of approx. 17 bar. The cycle starts all over again.
Depending on the evaporation temperature, a distinction can be made between low-temperature systems (up to 150ºC) and high-temperature systems (above 150ºC). The higher the temperature difference between the steam and condensation temperatures of the system, the more heat can be converted into electricity.