Analyzing solar installations: a catalyst or barrier to subsequent residential retrofits

This study investigates the impact of solar photovoltaic (solar PV) system installations on subsequent energy retrofitting behaviour among residential dwellings in Ireland, particularly within the context of the nation's commitment to sustainability and renewable energy as outlined in the National Development Plan 2021–2030. Despite over 65,000 solar PV installations facilitated by the Sustainable Energy Authority of Ireland (SEAI), findings suggest that the installation of solar PV does not significantly encourage additional retrofitting actions when compared to alternative measures, such as attic insulation and heating controls. Using statistical methodologies, including chi-square tests and survival analysis, the study reveals that homeowners who adopt solar PV systems exhibit a minimal propensity to pursue further retrofits, with an average additional investment of only €200 per installation. While the results indicate a nuanced relationship influenced by dwelling type and energy building rating (BER), the hypothesis that solar PV serves as a "gateway" to broader energy efficiency improvements is unsupported. The findings emphasize the need for integrated energy strategies that encompass both renewable technology adoption and comprehensive energy performance upgrades to achieve Ireland's ambitious climate targets. This research underscores the importance of fostering holistic approaches to retrofitting that encourage homeowners to invest not just in renewable systems such as solar PV but also in measures that enhance overall energy efficiency such as dwelling insulation.