Arctic rooftop goes vertical: 6,400 ballast-free solar panels beat the snow

A Tromsø cold store installed 6,400 vertical, upright solar panels on its flat roof, held only by friction with the membrane and with no ballast or penetrations. The east-west oriented, bifacial units shed snow and gain from reflected light on the white roof, improving yield in high-latitude winter conditions. The system—assembled in 1,600 prebuilt units by Over Easy—was installed in four days and has demonstrated a higher specific yield (about 747 kWh/kWp in Tromsø, versus ~485 kWh/kWp for conventional tilted rooftop arrays, though figures vary by site). If scalable, this ballast-free vertical approach could broaden rooftop solar viability in snowy climates, including parts of North America, though performance depends on location and roof albedo.