Database tools for policy development - presenting building stock renovation programme potentials through Energy Saving Cost Curves

The use of buildings databases has an enormous potential to inform decision-making in order to decarbonize the building stock by 2050. This paper showcases the potential of databases and, by using the example of Germany, it presents a methodology for appraising the economic and energy reduction outcomes of building renovation policies. A dynamic bottom-up simulation model, the Invert/EE-Lab, evaluates the effects of three scenarios of economic and regulatory incentives for three different renovation packages oriented towards the standards defined by the German building code (EnEV) as well as the support programmes of the Federal Development Bank (KfW). Results are presented visually through Energy Saving Cost Curves which communicate the energy savings and avoided energy costs following renovation programmes of the German building stock. The results show that under a range of realistic scenarios to 2030, the total economic energy saving potentials range from 60 to 170 TWh/y, and correspond to financial savings that range from 1.2 to 6.2 bne/y. Energy Saving Cost Curves provide a means to compare the impact of different policy options from the perspective of the investor for different building categories, and can thereby feed directly into the design of renovation strategies -whether at national, regional or city level- taking into consideration economic parameters ranging from subsidies and energy prices, to transaction costs, learning curves and discount rates.