Over Easy Solar has installed vertical photovoltaic panels on the roof of the Ullevaal Stadion, generating 219,000 kWh per year.
The world’s largest rooftop solar power system featuring vertical panels has been installed at Ullevaal Stadion in Norway, as reported by Interesting Engineering on August 2. The system at the national football stadium has a maximum capacity of 248 kilowatts (kW), and unlike many other systems that require months for installation, this project was completed in just a few days.
Rooftop solar power system at Ullevaal Stadion. (Photo: Over Easy Solar).
The demand for clean electricity is driving the world to seek innovative solutions for the installation of renewable energy sources. Over Easy Solar, based in Oslo, Norway, has found the perfect combination of installation location and vertical photovoltaic panel size to enable rapid deployment of rooftop solar. Traditional photovoltaic panel installations require large areas to achieve high capacity. However, horizontal panels require additional infrastructure such as inverters and mounting brackets, increasing the equipment’s weight and significantly limiting the number of suitable areas for solar deployment.
In contrast, vertical photovoltaic panels are relatively easy to install. By reducing the panel size, Over Easy Solar ensures that the installation weight is down to 11 kg/m2, making it convenient to install photovoltaic panels on many rooftop areas. The vertical design allows for the installation of bifacial panels, effectively doubling the production cycle of the panels. Vertical panels can generate more energy during the day compared to horizontal panels.
Thanks to this innovative approach, Over Easy Solar has installed the world’s largest vertical rooftop solar power system on the existing roof of the football stadium. The installation process includes 1,242 units with a maximum capacity of 200 watts over an area of 2,500 m2. Altogether, these units produce 219,000 kWh of electricity annually.
The company has installed the photovoltaic panels at a 20-degree southeast angle, allowing for better performance in winter when sunlight is limited. Additionally, the panels can achieve higher capacity due to the increased snow reflectance. Reflectance is the ratio of light or radiation reflected by a surface, with surfaces like snow or clouds having high reflectance due to their ability to bounce back a significant amount of visible light.
The installation of vertical panels also provides another advantage. The roof is very accessible for inspection and repairs at any time. The entire solar panel system was installed in just a few days, and some components of the panels can be disassembled for repair and reattached afterward.
