APPLICATION OF FREQUENCY DISTRIBUTIONS OF IRRADIANCE AND TEMPERATURE TO THE COMPARISON OF DIFFERENT PV TECHNOLOGIES

摘要

A "site profile" of solar radiation and temperature has been developed, using one year of one-minute instantaneous measurements made on a BIPV roof in Reading, UK. The site profile is the distribution of the solar irradiation over different levels of irradiance, with the average air and module temperature at each irradiance. The profile for the site used shows over 30% of the irradiation arrive at levels of irradiance below 300 W/m~2. The profile was combined with measurements of the perfornance of different types of PV module as a function of irradiance and temperature, for both peak power operation. This suggested that triple junction a-Si would perform substantially better than both CIS and c-Si, per Wp. This is primarily because a-Si performs better than the other technologies at the low levels of irradiance which dominate the solar supply at this site, and also because it is less influenced by high operating temperatures. a-Si also showed better performance for battery charging. The site profile summarises annual information in a simple way, and gives a rapid understanding of the site. It can be combined easily with information on PV performance.