Uncertainty in potential savings from improving energy label: A Monte Carlo study of the Swiss residential buildings

Abstract

This paper models scenarios for energy label based retrofit targets for Switzerland’s residential building sector for 2050. It takes into account the magnitude and uncertainty in the energy performance gap (EPG) between labelled and actual energy consumption using actual energy performance data, as previous work highlighted that the EPG is not evenly distributed across different building labels. A building stock retrofit model is developed to estimate the potential energy savings from improving building performance through increasing energy label rating. A Monte Carlo analysis is applied using real EPG distribution data. The uncertainty in total energy savings is calculated for business-as-usual case and for three scenarios based on the different retrofit incentive policies of different Swiss Cantons. This allows to quantify the uncertainties in energy and emission outcomes of different policy targets arising from the variable EPG. The results show that with the business-as-usual approach it is impossible to achieve the objectives set (9.7 Mt CO2-eq/y vs 0.4 Mt CO2-eq/y by 2050). On the other hand, to reach the targets, a more aggressive policy aiming at renovating all buildings to the highest standards is necessary, that translates into a renovation rate that seems unrealistically high (3.4% per year until 2050 vs the proposed 1.4%). The contribution is to inform stakeholders designing new policies (notably the EU Renovation Wave policies) of the risk related to energy policies.