The report by the German Environment Agency explores how to identify and support vulnerable households facing increasing fossil energy costs. Based on socio-economic and consumption indicators, it estimates that around three million households in Germany are at risk, mainly those reliant on fossil heating with low incomes and high energy demand. The approach draws on the French MaPrimeRénov’ scheme, which combines differentiated subsidies with efficiency targets.

The simulation calculates that improving efficiency by at least two classes (up to EH-70 standard) would require investments of around €72 billion for flats in multi-family buildings and €51 billion for single-family homes. With an 80% subsidy rate, annual costs over eight years would reach €15 billion, far exceeding the current Social Climate Fund budget (€1 billion per year). Even applying spending caps similar to the French model, the funding gap remains significant.

These upgrades could cut heating costs by up to 60%, delivering savings over 35 years. The study stresses the need to redefine support policies, mobilise additional resources, and prioritise efficiency to mitigate energy vulnerability.