Energy Efficient Homes in Germany: Lower Energy Requirement in the East and the South – Results of the ista-IWH-Energy-Efficiency-Index 2007
At the latest since the oil crisis in the beginning of the 1970s, energy efficiency of homes became a widely discussed topic. In the past, it were in first line aspects of the scarcity of fossil energy sources that motivated the debate. Nowadays, climate protection is a main goal of the European energy policy. For this purpose, a new instrument was introduced in 2009. Europe-wide, the “Energy Performance Certificate” for buildings presents detailed information on the required energy for heating, warm water and (indirectly) the resulting costs for tenants. This instrument is designed to provide further information for consumers to influence their behavior in favor of energy efficient buildings. Until now, there is only little information on spatial aspects of the energy efficiency of housing in Germany. This article presents data on the level of Germany’s NUTS2 regions. In our calculations, we include information on more than 2.6 million flats, interpolating it representatively for the total stock of multifamily buildings and considering the regional climate. The results of the first ista-IWH-Energy-Efficiency-Index indicate large differences between regions. The required energy for housing is much lower in the eastern and southern parts of Germany, compared to the western or northern parts. Explanations can be seen in a different structure of the housing stock (e.g. age of construction, level of refurbishment). Moreover, first analyses of the market structure indicate that owner occupied flats are more efficient in energy requirement than rental flats. Vacancy rates, the duration of occupation of rented flats and the level of regional income play an additional role for the energy efficiency of the regional housing stock.