Environmental Impact of Solar Home Systems in Sub-Saharan Africa

Abstract

Solar home systems (SHS) represent one of the most promising technologies for a rapid and independent electrification in those areas of Sub-Saharan Africa (SSA) without access to electricity. This study addressed the environmental impact of SHS in SSA through updated life cycle inventories and five impact categories: greenhouse gases (GHG) emissions, fossil fuels, metal and water depletion and human toxicity. Sixteen scenarios were considered, including manufacturing, transportation, recycling and user-related variables, such as the installation site, adequacy of SHS user operation and battery lifespan. The results showed that lead-acid batteries were the largest contributor to environmental impact among the SHS components, accounting for up to 36–76% of the environmental impact indicators. Apart from the components, user training for SHS operation, with the goal of maximizing usable energy and battery lifetime, proved to be critical to achieve improvements in the energy payback time and GHG emissions, which (under scenarios of high solar resources) can reach the range of 5.3–7.1 years and 0.14–0.18 kgCO2 eq/kWh, respectively. In addition, SHS GHG emission factors were benchmarked with those of other electrification approaches, such as national grids, 100% PV and hybrid PV-diesel off-grid mini grids and off-grid diesel generators. SHS achieved GHG emission factor values equivalent to PV-based mini grids in most scenarios and was strikingly lower compared to SSA national grids and diesel generators.