How Long Do Solar Panels Last? Lifespan, Degradation & When to Replace

The 25–30 year standard

Most panels carry 25–30 year performance warranties guaranteeing 90% output at year 10 and 80–85% at year 25. Quality panels degrade ~0.5%/year; budget panels ~1%/year. In practice, panels often keep producing well past 30 years at reduced output.

When replacement makes sense

Replacing panels early rarely pays — the new panels must cover their own cost. Replace when: panels fail (warranty), output drops dramatically, or you're already doing roof work and want a capacity upgrade. Check inverter age too — inverters typically fail first.

End-of-life options

Working old panels have a secondhand market (off-grid, agricultural, export). Failed panels can be recycled (~$15–45/panel) or, where allowed, landfilled. Keep documentation so future owners know the age and warranty status.

How long do solar panels actually last?

25–30+ years. Most warranties guarantee ~85% output at year 25; quality panels degrade only ~0.5%/year and often outlast the warranty.

When should I replace solar panels?

Only when they fail under warranty, output drops sharply, or you're upgrading capacity during roof work. Early replacement rarely pays for itself.

What happens to old solar panels?

Working ones have a secondhand market; failed ones can be recycled ($15–45/panel) or landfilled where allowed. Recycling rates are rising as costs fall.