Assessment of solar organic rankine cycle systems for power generation in Nigeria

Abstract Nigeria has abundant solar energy, especially in the north, which is underexploited. The solar organic Rankine cycle (solar ORC) converts low- to medium-temperature heat sources into electricity or heat. This study analyses the deployment of solar ORC systems in Nigeria, employing an evacuated tube collector (ETC) as the main heat source, focusing on the impact of regional heat sources on performance parameters, net power output, thermal efficiency, heat input, and turbine and pump work output. This study demonstrates a region-by-region comparison approach that integrates Nigeria’s solar energy resources with solar ORC performance. Six regions with heat source temperatures from 100 to 140 °C were analysed using R245fa. Direct normal irradiance data determined the regions’ highest solar potential. The northwest (140 °C) and northeast (135 °C) achieve the highest net power (47 and 48 kW) with cycle efficiencies of 18–19%. In the south-south (100 °C), net power drops to 37 kW, efficiency is 15%, turbine work is 38 kW, and pump work is 0.8 kW. Predicted efficiencies were consistent with previous studies reported in the literature. Net power, efficiency, and turbine work increase with heat source temperature. Future research should focus on site-specific studies to support technical viability before real-world applications.