Many German buildings need refurbishment plus heat pump to reach climate targets – report

Reducing the energy consumption of Germany's least energy efficient buildings is essential for letting clean heating technologies achieve the sector's climate targets, a report by the Heidelberg Institute for Energy and Environmental Research (ifeu) has found. Refurbishing the so-called worst performing buildings – those in the lowest efficiency ranking – is key for a successful energy transition, as well as for cushioning houesholds' energy bills and increasing resident comfort, it said.

Buildings in the lower efficiency classes F, G and H consume ten times more energy than newly constructed ones in class A+, the report commissioned by NGO Environmental Action Germany (DUH) said. This means that if these badly insulated buildings are fitted with a heat pump, their electricity demand would significantly increase, placing an excessive burden on the power sector. "Their hunger for energy can hardly be met affordably with renewable energies," the report said.

In their analysis, the authors assumed that 60 percent of Germany's buildings would be fitted with a heat pump by 2045. According to their calculations, if all buildings that currently fall into the worst three energy efficiency classes above are to be refurbished by that date, annual electricity demand from heat pumps could drop by 31 percent. Funding resources for energy-efficiency modernisations should therefore be targeted specifically at the leakiest buildings to ensure that the most urgent renovations are tackled first, the authors said.

DUH called for energy efficiency to play a bigger role in the ongoing coalition negotiations, noting that the topic has so far hardly featured in discussions. "Only if buildings in Germany are properly refurbished will it be possible to ensure that everyone can continue to pay their heating bills in the future and that the climate targets are met," said DUH head Barbara Metz. "It is alarming that the CDU/CSU and the SPD have so far criminally neglected this issue in their coalition talks."

Germany's next government is tasked with transposing the EU Energy Performance of Buildings Directive (EPBD) – which requires member states to reduce the average primary energy consumption of residential buildings by at least 16 percent by 2030 – into national law by May 2026. Annual renovation rates in Germany remain around one percent, and the country's buildings sector has missed its emission reduction targets since they were introduced.