District heating
District heating has various advantages compared to individual heating systems. Usually district heating is more energy efficient, due to simultaneous production of heat and electricity in combined heat and power generation plants. This has the added benefit of reducing greenhouse gas emissions. The larger combustion units also have a more advanced flue gas cleaning than single boiler systems. In the case of surplus heat from industries, district heating systems do not use additional fuel because they recover heat which would otherwise be dispersed to the environment.