Financial Analysis of a Desalination–Wastewater Recycle Plant Powered by a DC-DC Photovoltaic-Batteries System on the Aeolian Islands, Italy

The scarcity of drinking water is an increasingly pressing issue in many regions of the world, even in areas up till now considered developed. Climate change deprives many populations of the amount of water necessary for human consumption and traditional crops. Therefore, finding new water sources and making their usage more efficient and able to adapt to new environmental conditions without worsening the situation with further pollution is becoming mandatory. In the case study considered here, set on the Italian island of Vulcano in the Central Mediterranean, we propose the economic analysis and financial sustainability of plants for the desalination and recycled wastewater, powered by a DC-DC photovoltaic tracker system with silicon crystal panels sustained by a daily pack of lithium batteries. We present an estimation of the necessary budget, and propose a mix of traditional and innovative financial instruments to construct and analyse the economic trends of the installations over 30 years, considering the specific area price levels, salaries and interest rates. Finally, through the net present value index, we evaluate the financial sustainability of the entire operation, namely, identifying the circumstances when funding and building these plants in areas as remote as the one considered here is cost-effective.