Solar Thermal Potential in the Building Stock – Achievable Levels of Solar Thermal Energy Supply
Abstract
The solar thermal potential for domestic hot water and heating purposes has been assessed for over 1’000 existing buildings in Switzerland. The guiding principle of this study is i) to assess this solar thermal potential on a new solid basis starting from the buildings in different urban textures the way they exist today and ii) to analyze both the current potential with conventional systems and how the potential could develop along two axis: what is the potential with the same existing building stock being improved in terms of energy efficiency and / or using more advanced solar thermal (storage) systems? Two different building stocks have been examined, i.e. the densely urbanised area of the city of Zurich and the more rural area of the canton of Fribourg. The resulting achievable levels of the solar share in thermal energy supply in the residential sector vary from 19 to 43% for the city of Zurich and from 34 to 67% for the canton of Fribourg. Thanks to the innovative approach applied, detailed and corroborated results can be generated in an efficient manner and provide strategic input for decision makers in industry, research and policy on the important role of solar thermal systems in the energy supply in the residential building stock.