Dhe coalition peace is preserved, the confusion remains. The ban on fossil fuel heating, which is to take effect from January next year, is still one thing, a ban. But there has been a considerable number of exception rules, here the traffic light parties have softened a bit, there they have been tightened up. That should soothe the recently heated spirits of the public. With medium success. But at least one can assume that there will not be many fundamental changes to the legal text by the deadline in eight months. So time for a few explanations.
Because above all there is no way around her, at 65, in the future. It is the measure of all things in the amendment to the Building Energy Act, and it decides whether a new heating system has the government’s blessing. Every system installed after 2024 that is intended to provide warm rooms and hot water must in future run on at least 65 percent renewable energy. In a well-insulated new building, the heat pump is the superior system for this. It reaches the 65 percent for technical reasons alone.
The situation looks different in the existing building and also the specifications that will probably take effect soon. When replacing a heating system, most will use one of three routes to meet the requirements: also rely on electricity and install a heat pump, alone or in a hybrid solution, connect the household to a heating network or rely on green molecules made from gases or biomass. The good news: In many cases, no mathematical proof is required. If the owner selects an option from a fixed catalogue, the renewable target is considered to have been met.
Gas boilers for operation with pure hydrogen are still missing
Germany must be greenhouse gas neutral by 2045, and the country has made a legal commitment to do so. The heating sector is causing problems, more than 80 percent of our heating energy still comes from fossil sources, and almost every second household has a gas boiler. In 2021, according to the Federal Ministry for Economic Affairs and Climate Protection, gas heaters accounted for 70 percent of all newly installed systems. Greenhouse gas neutrality cannot be achieved in this way if a lot of green hydrogen, biomethane or e-fuels, CO₂-neutral molecules that replace fossil ones, are not quickly available by then.
The coalition’s revised draft has strengthened their role. Contrary to what was originally planned, new gas boilers may continue to be installed in existing buildings – provided they are “H2-ready”. They must run on at least 65 percent hydrogen. Modern gas boilers are already designed to cope with a certain proportion of hydrogen in the gas network or at least to be easily converted to it. As a rule, however, this is only up to 20 percent. Industry is still working on pure hydrogen boilers. Viessmann has announced such a boiler for 2025, and the company says that prototypes are currently in the testing phase.
When the devices come onto the market, one can speculate that they will cost more than the 8,000 to 10,000 euros that have to be paid for an ordinary gas boiler at the moment. Likewise, green hydrogen, if it is available at all, will remain an expensive raw material in the long term. The heating engineer Volker Schrörs, foreman of the Wiesbaden-Rheingau-Taunus guild, recently reported on this page that he sees no realistic use of hydrogen heating systems, at least in the next 20 years. The gas boiler, which then bears the “H2-ready” label, should initially be a significantly more expensive system that does nothing other than continue to burn natural gas.
