District heating is a network providing heat, usually in form of hot water. This heat is mainly used for space heating and for domestic hot water (drinkable water); however, It usually also meets some industrial needs. District heating systems can serve whole cities; when a system is limited to a group of buildings it is referred to as block heating.

The main advantage of these systems is that the large district heating plants are more efficient, more economic and create less pollution than decentralized fossil fuel based boilers. The heat generated in a centralized manner is then distributed to urban areas through a system of pipelines specially designed for transpo Solar district heatingting heat, which is then supplied house to house.