Photovoltaic-thermal system using shea butter as a phase change material for power generation in Nigeria, Sub-Saharan Africa

Abstract

Electricity demand in Sub-Saharan Africa is rising, and in Nigeria, over 40% lack access to electricity. A photovoltaic-thermal (PV-T) system was simulated in TRNSYS, using shea butter for active cooling of photovoltaic (PV) modules. Its performance was compared with that of conventional paraffin wax, and the effects of system design parameters were examined. Efficiency gains from using shea butter and paraffin wax were 0.18% and 0.03%, respectively, during peak solar hours. Notably, shea butter reduced cell temperatures by 1.75 °C during peak sunlight compared with paraffin wax. Peak electrical power and efficiency reached 130.53 W and 11.35%, versus 109.78 W and 9.10% for conventional PV. The optimal flow rate was identified as 2.0 LPM, with a shea butter layer thickness of 0.04 m to optimise thermal capacity and heat transfer. Environmentally, shea butter is renewable and biodegradable, with a lower carbon footprint of 2.20 kg CO2/kg compared with 3.78 kg CO2/kg for paraffin wax, according to CarbonCloud data. As a bio-based energy storage medium, shea butter not only reduces global warming potential but also supports the SDGs, including affordable energy, climate action, and responsible consumption.