Global cost advantages of autonomous solar–battery–diesel systems compared to diesel-only systems

• Global assessment of the potential for PV–battery–diesel systems.
• Combination of GIS analysis with energy system modeling.
• Calculation and comparison of the levelized cost of electricity of pure diesel systems and PV–battery–diesel systems.

Isolated diesel systems are the main electricity generation method in many rural areas nowadays and represent a viable option to supply un-electrified villages in the Global South. However, this generation scheme leads to a dependency on fossil fuels and their price volatility on a global market with a projected increase of costs in the future. At the same time, high carbon dioxide emissions increase environmental costs. Up to date, many hybrid mini-grid pilot projects and case studies were performed globally to assess how the inclusion of renewable energy in these systems can enhance technical and economic performance. This provides insights in local characteristics and challenges of that approach on a case by case basis. This study, on the other hand, takes a look at the overall global potential for solar–battery–diesel mini-grids for rural electrification and derives a comparative analysis of the respective regions. The introduction of a GIS-based analysis in combination with a sophisticated mini-grid simulation allows a highly automated approach to draw global conclusions with the option to downscale to local regions. The results of the methodology show that in many regions substantial LCOE reductions are achievable by introducing solar–battery–diesel systems compared to pure diesel systems. Furthermore, the crucial role of spatial varying of diesel fuel prices over different regions and the impacts on the feasibility of solar–battery–diesel systems can be observed.