An appraisal of the performance of a 10.5 kW SAPVS at a village in Ethiopia

In this presentation, the performance of a 10.5 kW stand-alone photovoltaics system (SAPVS) installation that has been in operation for over 2 years is discussed. Using standard parameters for similar systems, the technical features of the plant have been assessed. With a simplified but reasonably accurate approach, the average monthly insolation at the site has next been correlated with available meteorological data at the location. The computed results agree very well with the insolation values used by the designers. The study shows that only about 6% of the available solar energy is fed to storage batteries, and the final energy utilization amounts to about 3.9% of the incident insolation. Since its installation, the PV arrays have been used to charge batteries that are used to provide night-time lighting, and are disconnected as soon as the batteries are fully charged. The findings of the study suggest that instead of disconnecting the arrays after the batteries are fully charged, the energy could have been used for water pumping, grinding and other basic industrial purposes.