The building sector plays a significant role for the energy consumption in every country. New domestic buildings are often built with an envelope and heating system aimed at a low energy usage and with a potential for application of renewable energy technologies, such as heat pumps. For multifamily buildings, the challenge to apply heat pump technologies and renewable energy is more complex due to technical aspects as well as economical. While in some countries multi-family houses are often owned by local cities, communities or housing corporations, in other countries ownership is private and divided into separate flats.
Multifamily houses bring along a range of heat demand characteristics. Firstly the share of domestic hot water demand on the overall heat demand varies due to varying building standards as well as different climates. Secondly, the temperature level of the heating system is influenced by these aspects as well as by the installed heating transfer system. Henceforth, dealing with the variety of heat demand characteristic bears the challenge on the way to a broader spread of heat pumps in multifamily buildings.
Heat pumps – those powered by electricity, as well as those using fuel – have a significant potential for reducing the specific CO2 emissions for the heat supply in multifamily buildings. However, this potential is connected with special demands on both sides: the domestic hot water preparation and the heat transfer system (heat sink) as well as the utilization of environmental energy at site (heat source).