Life cycle assessment of a building-integrated solar technology

Abstract

Solar energy is a field that has grown immensely during the last decade, along with the in- creased public awareness of environmental challenges and sustainable development. While roof-installed solar cells have conventionally been mounted on aluminium panels, the idea of solar cells that are more integrated in the building design are gaining more and more in- terest. One innovation in this field is the solar sandwich, developed by SOLEV Entreprenad, which combines the functions of a roof with insulation and a surface where solar cells can be installed, without any conventional solar panels. This thesis consists of a life cycle assessment of this solar sandwich as well as life cycle as- sessments of two typical roofs with conventional solar panels. Four sensitivity analyses were conducted in order to investigate some of the methodological and modelling choices that were made. The results of these sensitivity analyses did not alter the final results signifi- cantly. This suggests that the model used for the calculations is robust. The results of the impact assessment show that the environmental impact of the solar sand- wich is similar to that of a conventional wooden roof with solar panels. In four out of five impact categories – global warming potential, acidification potential, human toxicity poten- tial and land use – the solar sandwich was found to perform better than the conventional roofs. The impact category where the solar sandwich performed the worst, by far, was strato- spheric ozone depletion potential.