Solar panels perform better under lower temperature conditions and green roofs lower the ambient air temperature. The plants from a green roof manage to moderate the heat island effect and reduce the air temperature through the process of evaporation. The plants absorb water and thus enhance water evaporation. Some scientists suspected green roofs may improve the performance of the photo-voltaic solar cells and thus began a study.
Researches from Bronx Academy of Construction and Design made an experiment with solar panel systems and with a smaller-scale green roof. Their study concluded that solar panels can be up to 3% more efficient when placed on a green roof. This is not the only study of its kind. According to ASES, the American Solar Energy Society, solar panels yield as much as 16% higher efficiency rates when places on green roofs. This claim is backed in theory by the fact that green roofs remove dust and pollutants from the air. It is thus possible to achieve such a high increase in efficiency especially in polluted areas.