A dam wall, 2,500 metres up in the Swiss Alps, freezing cold, buried in snow half the year.
Sounds like the worst possible place to build a solar plant.
Switzerland built one anyway.
And it's now generating three times more winter electricity than solar farms sitting comfortably in the valleys below.
Stay with me.
Meet AlpinSolar, bolted straight onto the Muttsee dam, the highest-altitude dam in Europe.
4,872 solar panels.
10,000 square metres of glass and steel, roughly one and a half football pitches, hanging on a vertical wall.
Critics laughed. Snow, sub-zero cold, no roads in, no easy way to even get equipment up there.
Turns out the "worst" conditions were the secret weapon.
Solar panels hate heat. They love cold.
And the Alps gave AlpinSolar three unfair advantages:
Result: 3.3 million kilowatt hours a year. Enough for 740 households.
No roads reach the Muttsee dam.
So 730 tonnes of equipment, including a crane that had to be dismantled and rebuilt, was flown up piece by piece by helicopter.
Workers clipped onto a rail safety system, suspended over a sheer drop, racing a 3-4 month window before winter snow returned.
Imagine that being your job site.
Switzerland has a "winter gap" — not enough power in the cold months, so it imports expensive electricity from abroad.
Alpine solar produces half its output in winter.
Lowland solar? Just 25%.
That's exactly why supermarket chain Denner locked in a 20-year power deal from this one dam wall.
Switzerland has since passed a fast-track law nicknamed the "Solar Express" to speed up Alpine solar projects.
New plants already dwarf AlpinSolar in size, with over 1.2 gigawatts of Alpine solar capacity planned across dams and ski resorts.
Turns out the harshest terrain on the continent might be Europe's best-kept energy secret.
That's all for now!
