There’s a persistent myth in the energy world that solar panels become useless once their 25-year performance warranty expires. But a new long-term study from Switzerland shows that’s simply not true. Researchers looked at six solar installations that have been in operation since the late 1980s and early 1990s and found that most panels still deliver more than 80 % of their original power output after 30+ years — far beyond typical industry expectations.

The key insight? Solar panels age slowly. In these real-world conditions, the average annual loss rate was about 0.24 % per year, lower than many earlier estimates and significantly slower than conventional warranty assumptions. That means well-built systems continue to produce clean electricity and reduce emissions — even after warranties expire.

For homeowners and clean energy advocates, this matters — because it strengthens the economics of solar power, extending the useful life of rooftop systems and increasing long-term returns on clean energy investments. And on a global scale, longer-lasting solar technology means more renewable electricity displacing fossil fuels over time, which supports firmer action against climate change