Impact assessment of public support for photovoltaic self-consumption

Photovoltaic self-consumption installations (PVSC) have grown exponentially in the Spanish electricity system since 2021. These installations, along the storage systems coupled to them, have also benefited from significant public aid during the same period. Such aid may have affected both the development of the sector and the competitive dynamics in the energy field and in other markets. The study analyses the various public support schemes offered at the national, regional and local levels in the form of grants, tax reductions and tax deductions. It assesses their impact on the penetration of the PVSC and, from there, evaluates their effect on competition. To strengthen the effectiveness and pro-competitive effects of these support measures, as well as to minimise possible competitive distortions, the CNMC recommends, first, reinforcing the institutional framework and coordination among administrations. This includes ensuring that the combined aid intensity does not exceed a certain threshold, implementing one-stop-shop solutions, and grouping incentives. Second, it proposes defining aid in terms of fixed unit amounts and regularly reassessing priority areas eligible for public support. Third, it suggests speeding up access to aid by streamlining administrative procedures and granting aid automatically where possible, expanding advance payment systems for subsidies, concentrating tax reduction in the first year, and considering the use of financial instruments.