The impact of a subsidized tax deduction on residential solar photovoltaic-battery energy storage systems

In May 2020, as a response to COVID-19, the Italian government introduced a subsidized tax deduction of 110% over five years for the realization of battery energy storage systems integrated into photovoltaic (PV) plants in residential settings. To assess the effectiveness of this measure, we applied an economic model using net present value, and we estimated the conditions under which economic feasibility would be reached, using break-even point analysis. The results showed that the 110% tax deduction significantly reduced the impact of the battery investment cost on profitability. The share of self-consumed energy emerged as the most significant determinant of economic feasibility.