The return of solar roofs on cars: an evolving technology
Solar roofs are making a comeback in the automotive industry. Once limited to powering cabin fans, integrated solar panels can now deliver an additional range of between 2,250 and 2,400 km per year under ideal conditions, according to estimates from recent models such as the 2025 Toyota Prius XSE Premium and the now-withdrawn Fisker Ocean SUV. This development is a significant improvement over the first attempts more than 10 years ago.
There are concrete applications, but the costs are still high
Fisker collaborated with Webasto to develop a retractable solar roof for the Ocean Extreme's high-end version, enabling an annual recharge of up to 2,400 kilometers. However, this system was only available on the most expensive models, costing US$68,000. Toyota now offers an optional $610 solar roof for the Prius XSE Premium with performance comparable to the Hyundai Sonata Hybrid Limited, a model that is no longer available in North America.
Potential limited by actual use
Despite the interest generated by this technology, the efficiency of solar roofs depends on parking habits. According to Ericksen Cooper, senior vice president at Toyota North America, "Most electric vehicle owners park their cars in a garage to charge them rather than outside in the sun." However, he points out that a return on investment in two to three years could appeal to cost-conscious customers, especially if additional solar panels were installed elsewhere on the vehicle.
Europe and China are driving markets
Webasto, a recognized supplier in the sector, estimates that the energy efficiency of solar roofs is currently 23%, a figure that could increase to 27% in the coming years. While Europe remains the main market for this technology, China is also showing growing interest. Despite pricing challenges, the outlook for North America remains positive. Jan Henning Mehlfeldt, a Webasto board member, says, "The roof remains the preferred location for integrating solar technology because it is visible, technological, and sustainable."
This is a solution to watch for the future
Although traditional panoramic roofs are still preferred by many customers, solar panels have returned to manufacturers' radars as a useful addition to autonomy, especially in sunny regions. With significant efficiency gains, interest could grow rapidly over the next decade.