This is the world's first high-altitude floating solar farm, perched like a raft atop Lac des Toules, a man-made reservoir near the village of Bourg-Saint-Pierre in the canton of Valais near the Swiss–Italian border. It is a one-of-a-kind power plant, installed in December 2019 by Romande Energie, the main supplier of electricity in French-speaking Switzerland. "We came up with the idea in 2012 over a coffee," recalls Guillaume Fuchs, project lead in wind and floating solar plants at Romande Energie. "We were thinking about ways we could use dams to produce more electricity. First we considered wind power but there were too many constraints. So then we looked into a project with floating solar panels."  

According to SFOE figures, electricity from renewable sources accounted for around 75% of Switzerland's electricity consumption and 62% of electricity production in 2019.  

The Lac des Toules solar project has cost CHF 2.35 million to date. It currently produces 800,000 kWh of electricity per year, which is enough to power 220 households. In recognition of its pioneering technology, Romande Energie was awarded the SFOE's 2021  Watt d'Or in the Renewable Energy category.