Performance analysis indices for Rooftop Solar Photovoltaic system

Abstract

The integration of rooftop solar photovoltaic systems into the electricity grid may be crucial in the current energy scenario. At present, this type of electricity generation is cost-competitive in many countries due to its modularity, the availability of the solar resource and the cost of the components, without the need for subsidies. Rooftop Solar Photovoltaic systems have the potential to cover 20-30% of electricity demand in Spain. In order to assess the potential of this technology and to facilitate the deployment of this type of systems, it is very important to provide a proper performance analysis of PV Rooftops systems from monitored data. In this way, self-consumption and self-sufficiency indices are commonly used, however they may not provide a complete assessment. Hence, indices such as the self-sufficiency index for sunshine hours, self-production index and grid-liability rate are also analyzed. These indices estimate the performance of rooftop solar PV systems and provide maximum and minimum values when estimated as a function of array peak power. Moreover, new indices such as the self-production index and the grid-liability rate for sunshine duration have been developed to estimate the system's performance during sunshine hours. These indices can complement the commonly used metrics and improve the performance analysis from monitored data. Moreover, they may also help determine the proper size of the array power of these systems in the industrial sector. The metrics are evaluated using data from four canning industries equipped with rooftop solar photovoltaic systems that have been monitored for a year.