Techno-economical analysis of building envelope and renewable energy technology retrofits to single family homes

In recent years, the popularity of single family homes, which have higher energy intensity than multi-family homes, has increased steadily in Turkey. This trend can be contributed to the interest of middle and high-income families towards living in larger homes, which also offer more privacy. Since multi-family homes are prevalent in Turkey, various studies are conducted to investigate the application of energy efficiency measures to these type of homes. Due to the increase in the number of single family homes and lack of research conducted to reduce the energy consumption for these type of dwellings, determining the feasibility of energy efficiency measures for the Turkish single family housing stock is an important concern. In this study, the techno-economic feasibility of applying a wide range of energy efficiency measures and renewable energy technologies to existing single family homes is investigated using monitored energy consumption data and building energy simulation program. The findings are extrapolated to the existing single family housing stock in three major cities of Turkey, namely Ankara, Istanbul, and Izmir, to estimate the potential for energy and emission reductions in Turkey. The results indicate that applying window glazing, roof, and a combination of window, wall, and roof improvements reduce heating energy demand by 21%, 34%, and 50%, respectively, with favorable payback periods. Among the renewable energy technologies analyzed, solar domestic hot water system results in the highest energy savings with the shortest payback period. Applying the combination of wall, window, and roof improvements and the retrofit of solar domestic water heating systems to existing single family homes in Ankara, Istanbul, and Izmir result in reductions of about 14 million, 8 million, and 15 million m³/year natural gas consumption in Ankara, Istanbul, and Izmir, respectively. These results can be used to develop policies for building insulation and equipment standards towards achieving low energy and emission national housing stock.