A Methodological Framework for Fostering Renewable Investments on Photovoltaic in Small Italian Islands

Abstract

In Italy, 19 small off-grid islands with a total resident population of about 50,000 inhabitants almost exclusively rely on carbon intensive diesel generators to produce electricity. As a consequence, high costs and greenhouse gas emissions, as well as low security of electricity supply make these islands economically and environmentally unsustainable. This paper proposes an integrated and comprehensive methodological framework for improving the sustainability of the small Italian islands through the introduction of renewable energy sources. The framework is composed of a prescriptive phase, where the renewable capacity targets to be ideally achieved and the most effective incentives for actually promoting renewable investments on photovoltaic are identified, and an assessment phase, where the effect of the incentives introduction is evaluated, providing policy recommendations for further promoting renewable investments. Results show that a relatively high renewable share can be ideally reached with low efforts in almost all the islands considered, and differentiated incentives for promoting investments are needed to account for the different geographical characteristics of each island. However, the analysis performed in the assessment phase shows that the decarbonization process is evolving very slowly and almost all the islands are far from reaching 2020 and, even more, 2030 capacity targets. The main reasons include the short time elapsed after the incentives introduction and a generalized lack of suitable sites for the deployment of photovoltaic plants, also due to the strict environmental constraints of these areas. Further actions to promote renewable development should go in the direction of fostering investments from private subjects and better harmonizing the energy and environmental objectives through a shared strategy for the enhancement of the sustainability of the island electricity systems.