Environmental and economic performance of solar mini-grids for rural electrification in Africa and evaluation of public policies to reduce their carbon footprint

Abstract

Ensuring universal access to reliable, sustainable and affordable energy by 2030 would require electrifying 600 million people in sub-Saharan Africa. In rural areas, mini-grids (MGs) based on decentralized electricity production (solar, diesel, hydro, etc.) and isolated from the national grid are one of the most interesting ways to achieve this objective at low cost, and there are several thousand MG projects already completed or under study on the African continent. Furthermore, this electrification must be compatible with the global pathways of carbon neutrality within a few decades in order to respect the Paris Agreement by limiting global warming below 2°C. This thesis evaluates the potential of hybrid MGs, based on solar PV, batteries and a diesel generator, to electrify rural areas in Africa while satisfying both constraints: low electricity costs and low greenhouse gas emissions.In a first chapter, we evaluate the minimum levelized cost of energy (LCOE) that can be achieved with 100% solar MGs. To do so, we simulate the operation of fictitious MGs on the whole African continent using meteorological data (irradiance, temperature) and idealized electricity demand profiles. We then show the strong sensitivity of the configurations (PV panel capacity, battery capacity) that minimize the LCOE to the characteristics of the solar resource and its temporal co-variability with the electricity demand.Even though these 100% solar MGs do not use fossil fuels, their carbon footprint (CFP) is not zero. The indirect CO2 emissions from the solar equipment and batteries are not negligible and in the second chapter we quantify their CFP which amounts to about 200gCO2/kWh. Moreover, the costs associated with these systems are much higher than those obtained with hybrid MGs using diesel. Our results show that including a diesel generator in the energy production reduces the cost of electricity production by about 30%, while doubling the carbon footprint. Thus, it