The heat pumps could be the only source for heating and/or cooling in the thermal grid or combined with other heat sources such as solar energy and combustion plants. They normally extract heat from a liquid or water source or from the ground but could also use ambient air as heat source.
In many cases, heat pumps are used to upgrade the temperature of waste heat to a usable temperature level for the heating needs of a building. The waste heat could for example come from sewage water, from data centres or from industrial processes.
Heat pumps are a vital part of so-called 5th generation district heating and cooling (5GDHC), which is a novel approach that uses a low-temperature, bi-directional network to enable the efficient sharing of heating and cooling between buildings. It integrates renewable energy sources and waste heat, allowing buildings to act as both consumers and producers (prosumers) of thermal energy. This system promotes flexibility, scalability, and potential cost reductions compared to traditional district heating systems.