District heating and cooling (DHC) is an integrative technology that can make significant contributions to reducing carbon dioxide emissions and air pollution while increasing energy security. A district heating network is a system that supplies the heat generated in a centralized plant to meet residential and commercial space and water heating requirements. A district heating scheme comprises a network of insulated pipes used to deliver heat, in the form of hot water or steam, from the point of generation to the end user.
District heating networks transport heat efficiently. Currently, they can be built in a distance of up to around 30 km from a generating plant and the distribution networks themselves can be hundreds of kilometres long. This is sufficient to distribute heat across cities, smaller communities and industrial areas. A network can easily be extended by simply adding more heat sources along the way. With respect to cooling, the DHC concept is implemented either through the distribution of chilled water or by using the district heating network to deliver heat for individual heat-driven chillers. DHC networks can distribute energy from various sources and integrate large scale storage while enabling the connection of several users, especially new buildings and refurbished buildings, with a decrease in the energy consumption of the district.