The EU’s residential and non-residential rooftops could host 2.3 TW of solar PV, generating around 2,750 TWh annually, according to JRC research
Residential buildings offer the largest potential, especially small homes, while mid-sized apartments face challenges due to multiple ownership and building rules
Currently, only about 10% of rooftops have solar PV, representing 215 GW, but the EU aims to add up to 200 GW more by 2030
Researchers stress that policymakers make rooftop solar deployment a key policy priority, considering the various benefits it brings
The European Commission’s Joint Research Centre (JRC) estimates that the European Union’s (EU) 271 million ‘geo-located’ buildings could host up to 2.3 TW of rooftop solar capacity. Using the current PV technology, assuming 22% module efficiency, this could produce about 2,750 TWh of electricity each year, meeting nearly 40% of Europe’s power needs under a fully renewable energy system scenario by 2050.
Most of this potential capacity, or 1,822 GW, will come from residential buildings (RB) and 519 GW from non-residential buildings (NRB).
Researchers used the open-access European Digital Building Stock Model (DBSM) R2025 to estimate rooftop solar potential across the EU. They define DBSM as a building-level database that provides consistent, high-resolution data for all 27 member states, creating a common solar mapping system for the region. It offers detailed information on solar resources and technical limits that they believe can help improve PV planning and decision-making at both individual and official levels.
DBSM’s estimate of 271 million buildings with technical potential for rooftop solar covers approximately 37,370 m². All systems were modeled with south-facing panels tilted at 20° and using 22%-efficient modules, in line with international standards. These conservative assumptions provide a realistic baseline for estimating Europe’s rooftop solar potential, while acknowledging that actual capacity will vary by building type and location.
Almost all EU nations have a technical potential exceeding 40 GW, raging from 32 TWh to 60 TWh depending on local solar irradiation, according to the researchers. While large nations such as France and Germany have the highest potential of 432 TWh and 394 TWh meeting over 80% of their current electricity demand, countries like Cyprus, Finland, and Sweden may see rooftop solar electricity generation providing over 50% of their 2024 electricity consumption.
Greece has a potential of 78 TWh compared to its 50 TWh consumption. Similarly, Hungary can generate 58 TWh vis-à-vis consumption of 42 TWh, and Romania offers 101 TWh of potential versus 44 TWh of consumption.
As per the findings, the size and type of buildings strongly determine how much rooftop solar Europe can install. Buildings larger than 2,000 m² offer the largest potential, accounting for 25% of the total technical PV capacity with 246 GW RB and 355 GW NRB capacity.
Across all member states, NRBs could cover 50% or more of their PV targets. Some could even exceed 95%.
Biggest opportunity among RBs lies in small homes, point out the researchers. RBs with floor areas between m² and 250 m² exhibit the highest technical potential, reaching 900 GW and accounting for 36% of the total potential capacity. These homes could generate about 1,018 TWh of electricity annually, claims the research. These households also tend to be the most willing to install solar, according to the research.
Mid-sized apartment buildings lag behind because of multiple ownership or tenants, and building rules, which pose a key policy challenge for the EU’s solar and buildings strategy.
Despite this large potential, only around 10% of rooftops across Europe currently have solar PV installed. Residential and non-residential rooftop systems together account for about 215 GW, or roughly 61% of Europe’s total installed solar capacity of 339 GW, according to the researchers. By the end of this decade, it is projected to reach 400 GW.
To align with the new rules under the Energy Performance of Buildings Directive (EPBD) that aims to make all EU buildings fully decarbonized by 2050, large NRBs (public and commercial, over 250 m²) are required to install rooftop solar from 2027, and all new homes to do so from 2030, wherever it is technically and economically possible (see Time For New European Union Buildings To Get ‘Solar Ready’).
Among the highest energy users in the European Union (EU), buildings account for a big share of climate-warming emissions. As up to 95% of the existing stock is expected to be still in operation by 2050, for the EU to achieve climate neutrality, several of these buildings will need to be renovated. These upgrades, the researchers stress, create a strong opportunity to add rooftop solar panels. More buildings will then become self-sufficient in their power generation, reducing their reliance on the grid.
Considering the significant benefits of rooftop solar, including carbon emissions reduction, enhanced rooftop cooling if combined with cool or green roofs, immediate reductions in energy bills, and an increase in property values, JRC recommends policymakers to prioritize accelerating rooftop PV deployment.
The complete research has been published in Nature Energy journal with the title Mapping Europe’s rooftop photovoltaic potential with a building-level database.