Heat pump districts are districts where heat supply is provided predominantly or exclusively by heat pumps.
What are heat pump districts?
In so-called heat pump districts, heat supply for space heating and domestic hot water is provided predominantly by heat pumps. These can be air-to-water heat pumps, geothermally fed brine-to-water heat pumps, or heat pumps connected to a 5GDHC network. Air source heat pumps are frequently used in new-build developments, where heat demand is low and only low flow temperatures are required in the heating system. The disadvantage of air source heat pumps is that, especially in densely built new developments, noise emissions can be too high, and neighbors may be disturbed by heat pumps running continuously, particularly in winter. The advantage of air source heat pumps is their low investment cost and simple, space-saving installation. Where air source heat pumps aren’t used, geothermal energy is the most common alternative. Here, geothermal boreholes are sunk into the ground, typically to depths of up to 100 m, since below this threshold special mining law regulations apply. The advantage of geothermal boreholes is that a comparatively high temperature level is available year-round. The disadvantage, however, is the high cost of drilling the boreholes. As an alternative to geothermal boreholes, near-surface collectors can also be laid in the ground. These collector loops are installed at a depth of around 1 to 1.5 m. This approach also achieves higher temperatures year-round than air source heat pumps. As a result, higher heat pump coefficients of performance can be achieved, reducing electricity consumption. A third option for tapping a heat source for heat pumps is 5GDHC networks, also known as 5th generation heat networks or anergy networks.
What is the advantage of heat pump districts?
The use of heat pumps is fundamentally the most efficient form of heat supply, which can be explained by the 2nd law of thermodynamics. A further advantage of heat pump solutions is that, unlike combustion processes, they can provide not only heat but also cooling. In this case, the heat pump functions like a refrigerator: heat can either be transferred into the building or extracted from the building and released to the environment. This cooling capability is available in principle across all heat pump systems, from air source heat pumps and geothermal solutions through to 5GDHC networks.