Performance evaluation of a 20 MW grid-coupled solar park located in the southern oceanic environment of Ghana

Abstract

In line with government efforts to increase renewable energy in the energy generation mix to 10 percent by the year 2030 and to promote cleaner production in the power sector, ambitious efforts are being made to promote the implementation of utility-scale solar PV plants with ample policy backing. However, performance information is not readily available since implemented large-scale projects are few. This study examines the performance characteristics of a 20 MW grid-tied solar PV plant located about 2 km away from the Gulf of Guinea at the Southern part of Ghana. The study uses a combination of PVsyst simulation and analysis of monitored data spanning the year 2018. The site meteorological data was obtained through NASA satellite and Meteonorm 7.1 station. Monitored data analysis showed that the power plant delivered a total annual energy of 26,480 MWh to the utility grid, whilst simulations gave total annual energy of 29,154 MWh. The final PV array yield values of 3.68 kWh/kWp/d and 4.06 kWh/kWp/d were obtained from the monitored and predicted analysis. Monitored data analysis gave plant performance ratio and capacity factor values of 72.8% and 15.1% whilst simulations produced 80.2% performance ratio and 16.6% capacity factor. The actual and simulated annual average system losses recorded were 0.056 h/d and 0.065 h/d, and the monitored and predicted overall system efficiencies obtained were 11.39% and 12.32%. Carbon emissions savings analysis revealed that the power plant saved 12,181 metric tons in the year 2018. The study gives an insight into valuable performance statistics, seasonal and year-round response relative to the coastal southern part of Ghana. The monitored data and operating experience of the PV system can be applied for the deployment of future large-scale projects in the southern part of Ghana, including other oceanic tropical climate regions in the world.