The Distribution of Energy Efficiency and Regional Inequality

This paper uses data on heating bills to study the distribution of energy efficiency outcomes in the German multi-apartment residential building stock. To uncover the underlying energy efficiency of buildings, we estimate the causal response of heat energy demand to variability in heating degree days. We examine the heterogeneity in temperature response using both fixed effects regressions and causal forests, and pay close attention to the regional socioeconomic distribution. Our results suggest that the distribution of energy efficiency is not equitable in the West of Germany. We show that although the newer and more energy-efficient buildings are located in the South of Germany, the older building stock in less prosperous East regions of Germany are surprisingly energy efficient, likely as a result of large investments in renovations post-reunification. Finally, we show that the regional distribution of energy efficiency reflects, in part, differences in heating needs - thus, the poorer energy standards of buildings in the North-West should be weighed against the warmer climatic zone.