Feasibility of 100% Renewable-Energy-Powered Microgrids Serving Remote Communities

This paper presents an analysis of the size of solar photovoltaic (PV) generation and battery energy storage system (BESS) necessary to power a remote community through renewable self-generation with minimum or no use of fossil-fuel-based generation. We analyze the case of an island in the coast of Maine, which is currently served by an aging subsea cable and a set of back-up diesel generators, and subject to very high electricity costs. We formulated an optimization problem to determine the optimal dispatching of the PV, BESS, and diesel generators to meet the hourly demand requirements at all times while minimizing the need for back-up diesel power generation. This dispatch problem is solved for multiple PV power sizes and BESS storage capacities. The results show that, under historical load and solar generation profiles, the island can be powered almost exclusively by renewable energy sources using at least a 400-kW PV and a 2-MWh BESS. We also analyzed the impact of prolonged periods of low solar generation in systems with an ultra-high share of renewable resources penetration. It was shown that these periods are the root-cause of the rising marginal costs in displacing fossil fuel generation as the penetration of renewable sources increases.