District Heating – Danish experience
Denmark belongs to the category of the most energy-efficient countries in the world. The widespread use of district heating and cogeneration of Electricity and Heat allows the country to improve energy efficiency and reduce greenhouse gas emissions for many decades. The first combined heat and power generation dates back to 1903. It concerned a waste incineration plant that allowed waste to be handled in an environmentally friendly way. At the same time, the system provided heat and electricity to a new hospital for the time.
During the 1920s and 1930s, a district heating system based on the waste heat was developed. It came from the local power plant. District heating also served urban areas with thermal energy. It then represented about 4% of the total heat supplied. Since then, the use of district heating from combined heat and power has been extended to the largest urban centers in Denmark. In the 1970s, about 30% of all homes used district heating networks.
At the time of the energy crisis in 1973/74, energy consumption per capita had risen to very high levels. This made it clear that it was necessary to save energy – including space heating energy – to reduce dependence on imported fuels and reduce consumer heating costs. It was therefore decided to extend the Combined Heat and Power System to fuel not only in the bigger cities but also in the medium and small cities in Denmark.
Today, 63% of Danish private heating is provided through district heating – not only for space heating but also for hot water. The document aims at a comprehensive presentation of the use of district heating in this country, the successfully followed model of development and technological applied innovations.