Overview
- BAFA and KfW updated the BEG guidance to require a CoC ESA‑based interoperable interface for certain heat pumps, and the rule takes effect for natural‑refrigerant models on 1 July 2027.
- The required application case asks a home energy management system to send a structured table of prices, flexibility and grid signals that the heat pump must read, interpret and negotiate with.
- Industry groups say that the specific CoC ESA format is not yet implemented in mass‑market heat pumps or household HEMS products, and the Bundesverband Wärmepumpe is asking for the deadline to be pushed, ideally to 2029.
- A separate rule already in force requires heat pumps above 4.2 kW to have a smart meter and makes subsidy approval contingent on the applicant ordering that meter for their connection.
- With heat pumps holding about 55–60% of the heater market and roughly 400,000 units expected this year, the change could disqualify many buyers from grants unless the government issues clarifications, transitional measures or a delayed timetable.