Comparative Performance of Various PV Technologies in Different Italian Locations

With the increasing number of photovoltaic (PV) installations on a worldwide scale, an outdoor performance analysis of various types of modules is needed. The purpose to assess and compare the performance of different types of modules in specific geographical locations, under various climatic conditions and to identify benefits/losses given by a specific surrounding context, is very important to evaluate the energetic behavior of future installations and direct them toward the most suitable technology to apply. The installations taken into consideration are located in Bolzano, Milan, and Catania, allowing comparison among three different Italian climate conditions and irradiance levels: the Alpine region, the upper Padana valley, and the see-side area in Sicily. In Bolzano, a multi-technology ground-mounted PV field is taken into analysis. For Milan and Catania, two multi-section PV power plants are monitored. The monitoring activities are done taking the international norm IEC 61724 as reference document, together with the best practice already existing in the field. The PV modules are evaluated in relation to ambient conditions, installation characteristics, module-specific behavior and state. Results are provided in a comparative way among the three considered geographical locations. Results are validated and an uncertainty estimation is shown. As instrumentation and environmental conditions are not the same, uncertainties for the locations might be different. Possible issues related to monitoring activities, as well as the performance of different PV technologies, will be highlighted.