In order to reach a high efficiency, sufficient thermal energy is required. In case of Hippothermie, the heat is extracted from a slurry or a dung heap. Therefore, corrugated stainless steel hoses with temperature sensors are concreted into the slurry and the dung heap. The storage volume of the dung heap should be about 30 m³. When used as ice storage, the storage capacity is about 1,000 kWh, which is sufficient for one week without external heat supply. The heat is then delivered to the heating network of a residential building.
The heat pump itself generates a heating output of max. 22 kW and consists of a reciprocating compressor with integrated frequency converter, several plate heat exchangers, an expansion valve and other accessories. A separate desuperheater heats the domestic hot water up to +70 °C. Hydraulically, the scope of the system includes a glycol pump and a hot water pump, as well as various valves. Based on measurements of the installed temperature sensors, the heat pump decides independently whether heat from the slurry or from the dung heap is used.