ORC Module

The district heating plant has the first ORC module (Organic Rankine Cycles) in South Tirol and one of the largest in Europe. The electrical capacity of the ORC module is 1500 kW; in optimal conditions the plant has already achieved a peak output of 1800 kW.

Plant engineering
The heat created during combustion heats up the thermal oil in the integrated boiler. The thermal oil loop transfers the energy to the ORC process. The principle of power generation by means of an ORC process corresponds to that of the conventional water-vapour process except for the fact that it oper-ates with an organic working medium instead of water. The organic working medium evaporates as a result of the heat exchange with the thermal oil in an evaporator and then expands via a turbine. The turbine drives a generator that generates electrical power. By means of internal heat exchange with a liquid in a regenerator, the vaporous working medium escaping from the turbine cools down to a level at which it does not quite condense. In the downstream condensator, the organic working medium continues to cool down and completely condense by means of heat exchange with the water from the process and heating loop. All of the cooling heat emitted in the condensator is available as usable heat for the distant heating grid. A circulation pump pressurises the condensed working medium back to the pressure required for turbine operation.