Environmental impacts reduction potential through a PV based transition from typical to energy plus houses in Thailand: A life cycle perspective

This study performs a comparative environmental life cycle assessment between typical, nearly net zero, net zero and energy plus houses in Thailand. It is demonstrated that over the life span of 50 years, in comparison to the typical house, the net zero energy house accounts for 81%, 77%, 90%, 63% and 69% less impacts in terms of global warming, terrestrial acidification, freshwater eutrophication, marine eutrophication and photochemical ozone creation, respectively. In a life cycle perspective, the energy plus house is found to be carbon negative and offers net savings towards terrestrial acidification, freshwater eutrophication, marine eutrophication and photochemical ozone creation as well; thanks to its ability to export roof top PV generated electricity to the public grid. The energy plus house is, however, noted to account for 35% higher metal depletion potential in comparison to the typical house. Despite offering considerable environmental impacts reductions in a life cycle perspective, these energy efficient houses are noted to account for higher embodied impacts associated with their manufacturing and maintenance stages in comparison to a typical house. PV panels account for most of these additional embodied impacts and particularly for the energy plus case, are noted to dominate all other materials, even concrete and steel.