Heating Transition at Risk: What Ending the Heating Act Would Mean

Why are heating basements important for climate protection?

The climate policy of Angela Merkel and her black-red government violated the rights of future generations, ruled the Federal Constitutional Court five years ago. With the Climate Protection Act (KSG) the Federal Republic has since committed to reducing its greenhouse gas production by 65 percent below the 1990 level by 2030. So far only 49 percent has been achieved. Under the Black-Red coalition, climate protection has weakened recently: in 2025 emissions fell by only 1.5 percent. Therefore, in the next four years, 4 percent per year are necessary to comply with the law.

Germany lags behind especially in heating and cooling buildings. In heating basements, almost one fifth of the total greenhouse gas burden, around 18 percent, arises. The gas heating—or, even worse, the oil heating—is what the internal combustion engine on the roads is: a technology from a time when humanity lived in fossil intoxication and believed there would be no consequences.

What was in the old heating law?

There have long been climate-friendly alternatives, such as solar thermal energy, heating with sunshine, or pellet heating, in which renewable biomass is burned. The most sophisticated and widespread is certainly the heat pump. It needs only one kilowatt-hour of electricity to extract three additional kilowatt-hours of energy from the surroundings, for example from the air. This yields a total of four kilowatt-hours of energy for heating. If the electricity is produced by sun or wind, the heating runs climate-neutral.

Therefore the Ministry of Economic Affairs, led by Robert Habeck (Greens), created the Building Energy Act (GEG), which generously promotes heat pumps. Socially disadvantaged households received 70 percent of the purchase price. It was also prescribed that in new buildings 65 percent of heating energy must be fossil-free. This was intended to kick-start the heat transition.

What does the new law say?

A draft of the Habeck bill was leaked in 2023, the Bild-Zeitung invented the “Heating Hammer” and gave the impression that all homeowners must switch to heat pumps. That was already false at the time, but the Union jumped on the campaign wagon and criticized that the GEG no longer allowed “technology openness.” Their campaign promise: Habeck’s law would be scrapped.

Now Black-Red has indeed agreed on key points for a Building Modernization Act (GMG). According to this, inefficient oil heating and the gas technology from the last century are allowed again in new buildings; the 65 percent renewable quota has been scrapped. A so-called “bio staircase” instead provides that the share of climate-neutral fuels will gradually increase by 2030. New gas or oil heating systems should use at least 10 percent of them by 2030. In the case of natural gas boilers, biomethane or hydrogen should be used and in addition to heating oil, synthetic fuels, so-called “E-Fuels.” The law is to take effect on July 1.

Does this help climate protection?

Unfortunately no. Biogas is produced by fermenting organic substances in biogas plants. The main substrates are slurry, manure, or energy crops, primarily maize. Although there are producers who already feed biogas into the natural gas network, biogas is mainly used in combined heat and power plants for electricity and heat generation. Only 1.3 percent of biogas is currently in the natural gas network; production would have to rise rapidly — which would lead to a maize monoculture of the landscape and have grave consequences for biodiversity and species protection.

The poor quality of the proposed points becomes evident with hydrogen. First, you cannot simply use this highly reactive gas in a gas boiler; the equipment is not designed for it. According to calculations by Holger Quaschning, Professor of Renewable Energy Systems, its use is second, four times as expensive, i.e., economically unsound. Third, there is not enough hydrogen. The same applies to “E-Fuels.”

What does the new law mean for industry?

Sadly, not much good either. Because gas boiler builders do not have to abandon fossil fuel propulsion, the push for innovation wanes. For the builders and installers of heat pumps, at least, the major uncertainty is resolved: until 2029 there should still be subsidies for all those who choose a heat pump.

Only for the fossil gas industry does the law bring advantages: operating and maintaining the gas network costs a lot of money, and with every new heat pump there is one fewer gas connection to which network costs can be allocated. Not surprisingly, Federal Minister for Economic Affairs, Katherina Reiche (CDU), is pushing for a stop to the heat transition. A year ago she was still a top executive of the Westenergie group—one of the subsidiaries of the former fossil-fuel giant E.ON, which also operates a 37,000-kilometer natural gas network.

And what does it mean for consumers?

A large drain on the wallet — at least for those who still opt for an old fossil-fuel heating system. In 2028 the second part of the EU emissions trading system begins: allowances for greenhouse gas production will no longer be allocated free of charge; their price will be determined on the market. And because the EU spends less to achieve its climate target, natural gas and heating oil will become much more expensive than today.

Because grid costs are projected to rise, some municipal utilities have announced plans to shut down their networks — Mannheim from 2035, Hannover and Würzburg by 2040. Anyone who installs a new gas boiler now might face a problem in 2041, when it first breaks after 15 years: will anyone still be able to repair it?

What gives hope?

The Federal Constitutional Court. It is currently examining a reform of the Climate Protection Act, in which the traffic-light government had weakened the black-red law in 2023. Climate protection advocates had challenged this. Hearings on the matter have already concluded, and a verdict is expected in spring.