Solar Cars Prove Viability on European Roads: TNO Study
The Hague, Tuesday, 9 September 2025.
TNO’s study confirms that solar-integrated vehicles can significantly reduce emissions, with solar panels covering up to 50% of energy needs in Southern Europe.
Introduction to the Study
A recent study led by the Netherlands Organization for Applied Scientific Research (TNO), in collaboration with the Fraunhofer Institute for Solar Energy Systems and three automotive solar technology firms, has confirmed the feasibility of vehicle-integrated solar panels. This study, conducted over nine months, assessed the performance of solar cars across European roads, revealing substantial potential for reducing carbon emissions and advancing sustainable transportation. The research not only aligns with the Netherlands’ climate goals but also reinforces its position as a leader in green automotive technology [1][2].
Findings and Implications
The study included 18 vehicles, including trucks, buses, delivery vans, and passenger cars, equipped with rooftop and side-mounted sensors. These vehicles traveled more than 1 million kilometers since March 2024. The data confirmed that rooftop solar panels receive an average of 2.8 kWh/m² per year, while side panels receive about 1.3 kWh/m² per year, which is approximately 50% less irradiance [1][3]. According to Lenneke Slooff, a senior consultant at TNO, these findings validate previous modeling assumptions and highlight the importance of optimizing panel placement [1][4].
Potential Energy Contributions
The initial results from vehicles such as the Lightyear 0 show a strong correlation between simulated and measured data for solar yield and energy consumption. Vehicle-integrated photovoltaics (VIPV) can contribute up to 50% of the annual energy consumption for passenger cars in Southern Europe and 35% in Central Europe. However, further seasonal data, particularly from spring and summer, is necessary to confirm long-term trends for different vehicle types [1][3].
Future Prospects and Expansion
To improve geographic and seasonal coverage, the SolarMoves project plans to expand its measurement campaign into Southern and Eastern Europe during the summer of 2025. The final report, expected in 2026, will provide updated findings and recommendations for optimizing the use of integrated solar cells per vehicle type and region [1][3]. Christian Braun, a senior engineer at Fraunhofer ISE, emphasized the need to refine shading models and incorporate route-location-specific data to enhance the accuracy of VIPV performance predictions [1][4].