Cost-Effective Energy Transition: Rooftop PV in European Union Buildings

The building sector, recognized as the largest energy consumer within the European Union (EU), plays a pivotal role in achieving the climate ambition of a decarbonized society by 2050. Crucial aspects of the clean transition involve reducing energy demand and increasing reliance on renewable sources, particularly solar energy. This paper explores the significance of rooftop photovoltaic (PV) systems in reaching cost-optimal levels of primary energy demand in buildings by analyzing recent data from EU Member States. The findings reveal that integrating rooftop PV can yield, on average, energy savings of around 30-35% for new buildings and around 20% for renovated ones. However, the results also show that global costs can both increase and decrease with the installation of PV systems, depending on the level of energy savings achieved. In scenarios where energy savings exceed 30%, PV variants are generally cost-effective, whereas for savings below 10%, PV installations may not be the most economically viable option. These aspects are particularly important since such calculations and their results are used to benchmark the national level of energy performance of buildings. The findings highlight rooftop PV as a crucial technology for meeting the goal of Zero-Emission Buildings as of 2030, where on-site carbon emissions will be prohibited.