Assessing energy efficiency potential in the building stock: Method for estimating the potential for improvements and their economic effects: Dissertation

Buildings, representing more than a third of global energy consumption, have long remained one of the focal points for the efforts to increase energy efficiency. The residential sector in particular has had more energy-related policies put in place than any other sector in the IEA countries. Therefore, the question which policies will have the greatest effect over time is very relevant to the policymakers. The main objective of this thesis is to develop a method for calculating the en-ergy efficiency potential of the building stock and to assess the economic effects of the realization of the potential in terms of changes in GDP, employment and external costs. Even though the method is meant to be applicable to different building stocks, the Finnish building stock was mostly studied as the method was developed over time. Similar but more limited analysis was also conducted for a number of EU member states. During the course of the study, a calculation tool called REMA was developed based on the methods used. The purpose of REMA is to allow conducting similar analyses in the future with relative ease in a systematized way. REMA is a bottom-up engineering model of energy use in the building stock. Future developments are estimated using annual rates of new construction, renovations and removals from the building stock. The selected approach entails selecting representative building types, also called archetypes, for estimating the energy consumption in different segments of the building stock. The scenarios calculated concerning the Finnish case indicate that a few per-cent rise in annual construction and renovation investments can decrease total primary energy consumption 5-7% of the country by 2050 compared to a baseline scenario. On the short term a slight decrease in the level of GDP and employment is expected. On the medium to long term, however, the effects on both would be positive. Furthermore, a significant drop in harmful emissions and hence external costs is anticipated. Overall, a clear net benefit is expected from improving energy efficiency. For other EU countries studied, typically energy savings of about 20% were estimated to be achievable by 2030 with cost-effective renovation investments in the building stock analysed. Overall, major economically sound energy efficiency potentials were identified, but the realization of these potentials is rather slow due to the limited renewal rates present in building stocks.