District heating operating principle
District heat mostly comes from combined heat and power plants or from heat-only plants. Fuel for district heating can include natural gas, coal, peat, wood or landfill gas. Almost 80% of district heating comes from combined heat and power plants, excess industrial heat or from burning landfill gasses.
Connecting to district heating
In order for a customer to connect to district heating, she or he must first confirm the availability of district heating in his or her municipality. Next, the customer must obtain a district heating substation, which can be purchased, with installation, from a heating contractor or as a turnkey delivery from an energy or district heating company.
District heating delivery
In a district heating network, heat is transmitted to the customer as hot water. The water is transferred to the customer’s heating substation where heat exchangers are used to give off heat for the heating network and for heating domestic hot water.
This heat can be used for ventilation or to heat rooms and domestic hot water. The cooled water then returns back to the production facility to be reheated.
A reliable form of heating
The delivery reliability of district heating is almost 100%. District heating customers spend only 1–2 hours per year without heat on average.
Outages may arise from damage to the network and its repair, or during the connection of new customers to the district heating network. Attempts are often made however to time outages outside of the heating season using temporary solutions.