What is district heating anyway?
District heating is heat that is not generated in the residential building, but comes from a power or heating plant in the area. Water is usually heated there, which is then conducted through insulated pipes to the consumers. When it arrives in a residential building, hospital or office building, the energy is transferred to the building’s heat circuit in a transfer station, where it provides room heating and hot water. The buildings do not need their own heating system.
How is the heat generated in the power plants?
According to the district heating trade association AGFW, this is currently mainly through the combustion of natural gas and coal, mostly in so-called combined heat and power generation, in which electricity is also generated in addition to heat. Around 70 percent of the energy comes from fossil fuels. The remaining 30 percent comes from heat from the incineration of waste or biomass (wood chips), as well as from geothermal energy and other renewable sources.
How many district heating networks are there in Germany?
According to the district heating association AGFW, almost 3,800. They are operated by around 500 companies. In 2020, the total route length was over 31,000 kilometers. According to the energy industry association BDEW, 14.2 percent of the 43.1 million apartments in Germany were heated with district heating in 2022, which is about every seventh apartment. The proportion has steadily increased over the past 20 years. In 2003 it was 12.4 percent.
How climate-friendly is district heating?
According to the consumer center, this varies greatly depending on the energy source, the efficiency of generation in the power plant and the level of line losses. “The use of combined heat and power has a high energy yield, and the use of waste heat, for example from waste incineration, makes sense.”
Can households switch providers?
No. “In the case of district heating, it is not possible to change the heat supplier,” explains the consumer center. Planning and operation of the power plant and the grid would be in the hands of one company. The construction of a double infrastructure by another company is uneconomical. “Therefore, every district heating company is a local monopolist.” The consumer advocates point out that municipalities provide for compulsory connection and use for some properties. “As the owner, you are then forced to supply your house with district heating.” The legal basis for the use of district heating is bundled in a separate ordinance.
When is district heating suitable?
According to the consumer center, district heating pays off when as many users as possible are connected to the heating network. “Because the laying of the grids and the construction of the generation plants are usually associated with considerable costs.” District heating is therefore particularly suitable in densely populated (new construction) areas.
How does the federal government rate district heating?
As very important. In the first draft law for municipal heating planning, which has recently become known, the Federal Ministry of Building states: “The expansion of district heating and the decarbonisation of the pipe-bound heat supply are of outstanding importance for achieving the federal climate protection goals.” In recent years, the investments required for this have not been made to the required extent.
The expansion should be laid down in the law: “Heating networks should be significantly expanded in order to achieve an economically cost-efficient, climate-neutral heat supply and the number of buildings connected to heating networks should be increased significantly and dynamically,” says the draft bill.
Heating law with specifications for heating networks
In the planned building energy law, the so-called heating law, specifications for heating networks are also planned. There should be an obligation to use at least 50 percent renewable heat or waste heat in existing heating networks by 2030. A share of 65 percent is to be demanded for new heating networks.
What does the industry think of an expansion?
By 2050, under certain conditions, it believes that there will be three times as many heating grid connections as possible today. While 6 million of the 43 million apartments are currently heated with district heating, there could be 18 to 20 million in the future, especially in apartment buildings in cities and in densely populated areas.
District heating is “the key to climate-neutral cities”
“District heating is the key to the issue of climate-neutral cities in Germany,” says the deputy managing director of the AGFW trade association, John Miller. The association criticizes the schedule provided for in the Building Energy Act to convert existing heating networks to at least 50 percent renewable heat or waste heat by 2030.
The association calls for longer transition periods and significantly more funding, especially for the “Federal Funding for Efficient Heating Networks” (BEW) program.