Rooftop solar could meet 40% of EU’s long-term electricity demand

The rooftops of EU's 271 million buildings could host around 2.3 terawatts peak (TWp) of solar photovoltaic (PV) capacity and generate approximately 2,750 terawatt-hours (TWh) of electricity per year with current PV technology, according to a new study. This would provide 40% of the electricity needed in future zero emission scenarios, underlining how rooftop PV could play a decisive role in meeting both near- and long-term EU climate and energy objectives.

This work presents, for the first time, per-building rooftop solar-PV estimates at the EU scale, by exploiting an updated EU-wide model of the building stock together with national administrative data. It also takes account of recent improvements in PV technology, which has seen energy conversion efficiency jump from 18% in 2018 to 22% in 2025 and the higher power density possible on flat roofs typical of large commercial buildings.

More precise energy planning

The study, published in the Nature Energy journal, is based on the first EU-wide analysis assessing residential and non-residential rooftop PV potential separately, at the level of individual buildings. It relies on the latest release of the European Digital Building Stock Model (DBSM R2025), a high-resolution geospatial dataset covering 271 million buildings in the EU. This bottom-up approach enables analysis to scale from individual buildings to neighbourhoods, cities, regions and the entire EU, supporting more precise, evidence-based and targeted energy planning.

Rooftop PV technical potential

The study finds a total potential EU rooftop PV capacity of approximately 2.3 TWp, broken down as follows:

-Residential buildings: ~1,800 GWp

-Non-residential buildings: ~500 GWp

If fully used, this could generate around 2,750 TWh per year, equivalent to about 40% of electricity demand in a 100% renewable EU energy system by 2050.

Contribution to EU energy targets

By 2030, more than half of the EU's PV capacity target of 700 GW could be met using non-residential rooftops. Large buildings, exceeding 2,000 m² in roof area, could potentially host around 355 GW. In several Member States (Cyprus, Finland and Denmark), non-residential rooftops could meet 95% or more of national PV targets set in the National Energy and Climate plans (NECPs) 2021-2030, updated in 2024, , while the full use of rooftop PV potential would exceed the solar capacity required in net-zero scenarios for 2050.

A major untapped opportunity

Up to now only around 10% of European building rooftops are equipped with PV. Yet rooftop systems already represent the majority of EU solar capacity, accounting for about 61% of the 339 GWp total installed PV capacity in 2024.

Buildings are responsible for around 42% of EU energy consumption and 36% of energy-related greenhouse gas emissions, making them a central focus for climate action. The sector needs to switch from fossil fuels to clean electricity - according to Eurostat the current electrification rate for households in the EU is still only 26%.

With most of today's building stock expected to remain in use through 2050, integrating rooftop PV into renovations offers a powerful opportunity to cut emissions, reduce energy bills and support electrification with heat pumps and electric vehicle charging. The solar mandate in the Energy Performance of Buildings Directive will speed up the uptake of solar installations in new and renovated residential and non-residential buildings.

Background

The publicly available DBSM R2025 dataset provides a practical tool for policymakers, planners, utilities, and investors to design faster, fairer and more targeted rooftop PV deployment strategies. The researchers from the Joint Research Centre have also published their code for the analysis enabling stakeholders to do further studies on this basis.

This work supports decentralised energy systems aligned with key EU initiatives, including the revised Energy Performance of Buildings Directive, RePowerEU plan and the European Solar Rooftops Initiative.

Related links

Mapping Europe's rooftop photovoltaic potential with a building-level database

Details