A Preliminary Energy Assessment to Improve the Energy Sustainability in the Small Islands of the Mediterranean Sea

Power plants supplied by renewable energy sources are expanding around the world, in order to reduce the carbon dioxide emissions, limit the global warming and improve the energy sustainability. Despite the relevant achieved results, small islands are heavily reliant on fossil fuels. In this context, renewable energy sources are available but practically unused, due to landscape and economic constraints. This condition is quite common in the Mediterranean Sea. These islands are normally fed by a stand-alone electrical grid and a power plant, equipped with diesel engines. In order to improve the sustainability of the energy sector, the paper considers the case study of Ustica, a small Italian island located north of Sicily. Starting with the analysis of the electrical energy consumption of public buildings, the paper suggests a more sustainable energy mix, based on solar and sea wave. An innovative technology is presented to exploit the sea wave energy source while commercial photovoltaic panels are adopted for the utilization of solar radiation. A mathematical model is introduced to realize a preliminary sizing of the energy mix. An environmental and economic evaluation is performed, demonstrating the feasibility of this solution. The approach reported in this paper can be easily replicated in other small islands, obtaining similar results.