The Assessment of Localized Clustering of Photovoltaic Plants in Italy: The Role of Financial Incentives

Abstract

In recent years, the rapid growth of renewable energy sources (photovoltaic, biomass, geothermal, wind and hydroelec tricity) constitutes a feasible solution for environmental problems created by the present production-consumption en ergy model. Photovoltaic (PV) is one of the most promising, renewable energy sources with great potential for devel opment. Over the last decade, the diffusion of photovoltaic installations in Italy has recorded a considerable increase, displaying at the same time substantial regional dissimilarities. In this paper, we sustain the hypothesis that the installa tion of PV plants is first of all driven by the financial incentives granted. Using data for Italian provinces, derived under two different editions of the Energy Account, which represents the current Italian financing mechanism, we apply a statistical cluster detection method (the spatial elliptic scan statistics) to identify differences in the spatial distribution of PV plants, in terms of most concentration, throughout the Italian territory. The focus is on mapping the clusters and checking their spatial stability over time, when different subsidy schemes have been adopted. The evidence shows that in the latest detected clusters there are many Northern Italian provinces, with adverse climate conditions (low global irradiance level, low annual temperatures), which have rapidly taken advantage of incentives for solar energy installa tions.