Economic and Environmental Analysis of Photovoltaic-Thermal Systems Integrated with Shea Butter as a Phase Change Material in Nigeria

ABSTRACT: The literature documents the economic and environmental evaluations of conventional phase change materials (PCMs), such as paraffin wax, used in photovoltaic-thermal (PV-T) systems. Nonetheless, there is limited evidence of bio-based PCM applications within PV-T systems. This study investigates the economic and environmental aspects of employing shea butter as a bio-based PCM in a PV-T setup. The photovoltaic-thermal system integrated with shea butter was designed using the Transient Simulation System (TRNSYS). The shea butter system showed superior economic performance, with a levelized cost of energy (LCOE) of US$0.131/kWh, compared with US$0.146/kWh for the paraffin wax system. Its energy costs were also lower than those of the grid and diesel generation in Nigeria. However, the payback period was longer than that of traditional PV systems. Environmentally, shea butter has a global warming potential (GWP) of 0.615 kg CO₂e, significantly lower than that of paraffin wax (3.75 kg CO₂e).