From shine to decline: Degradation of over 1M solar PV systems in Germany

Australia has a lot of solar panels, a good number are hitting the 30 year mark.

Buried in that longevity, is an observation that a fifth of panels degrade faster than expected

  The long tail appears on graphs showing the degradation rate per year of the panels, indicating that up to 20% of all samples perform 1.5 times worse than the average.  

and discussion: Maximising time in the sun: how to maintain and repair solar panels to make them last (2026) - https://www.theguardian.com/australia-news/2026/feb/13/maxim...

"Fleet-scale, real-world solar performance ratio declines by 0.59% per year."

I've heard 1% before.

At 0.59%, the panels reach 80% after about 35 years. By which time they may be at 60% of whatever panels are on sale then.