Benchmarking the measured energy use of Nordic residential buildings and their Zero Energy-readiness

Abstract

It is well known that buildings are responsible for a nearly 40% share of the total energy consumption; in order to reduce it by improving the energy efficiency of the building stock, it is necessary to first evaluate their performance. Building energy benchmarking provides information to stakeholders and motivates energy retrofits, by evaluating and comparing a building to similar units and/or to a reference building in terms of energy consumption with the minimum amount of data possible. Towards this end, in this paper we analysed nearly 19000 Estonian Energy Performance Certificates (EPCs) of detached houses. By means of a systematic statistical investigation, we determined the time evolution of EPC labels and evaluated the impact of incentives pre/post renovations, drawing a comprehensive and updated picture of the Estonian detached houses. This allowed evaluating their readiness based on recent trends: unfortunately, new or renovated dwellings are not estimated to achieve the zero-energy status by 2050. Although marginally due also to the use of homeworking during the COVID-19 pandemic, we show that this is mostly determined by changes in the regulations. A benchmarking ranking for each construction type was also created by calculating rating tables based on a 0-100 coefficients scale; this allows comparing with the existing stock any building with known EPC, for energy Audit and other investigations aiming at energy efficiency.