HowLongFor

How Long Do Solar Panels Last?

By the HowLongFor Editorial Team

Quick Answer

Most solar panels last 25–30 years, and many keep producing usable power for 30–40 years. Panels degrade slowly, typically losing about 0.5% of output per year.

Duration by Type

Monocrystalline panels(most common)25 years – 40 years

Highest efficiency and longest lifespan.

Polycrystalline panels25 years – 35 years
Thin-film panels10 years – 20 years

Lower cost but faster degradation.

String inverter (component)10 years – 15 years

Usually needs replacement before the panels.

Quick Answer

Modern solar panels are built to last 25–30 years, which is why most manufacturers offer performance warranties for that period. Panels don't suddenly stop working—they degrade gradually, often still generating 80–90% of their original output after 25 years and continuing to produce power for 30–40 years or more.

Solar Panel Lifespan by Type

Panel TypeTypical LifespanNotes
Monocrystalline25–40 yearsHighest efficiency and longevity
Polycrystalline25–35 yearsSlightly lower efficiency, still durable
Thin-film10–20 yearsCheaper, shorter lifespan, faster degradation

Understanding Degradation

Solar panels lose a small amount of efficiency each year, a process called degradation. The average degradation rate is about 0.5% per year, though high-quality panels can be as low as 0.25%. At 0.5% per year, a panel still produces roughly 87–88% of its original output after 25 years.

Years in ServiceApproximate Output Remaining
0 years100%
10 years~95%
25 years~87%
30 years~85%
40 years~80%

Factors That Affect Solar Panel Lifespan

  • Panel quality — Premium panels degrade more slowly and last longer.
  • Climate and weather — Hail, heavy snow, and extreme heat add stress.
  • Installation quality — Proper mounting and wiring prevent early failures.
  • Maintenance — Keeping panels clean and inspecting for damage extends life.
  • Component wear — Inverters typically fail sooner and need replacement.

Other Components and Their Lifespans

While the panels themselves last decades, other parts of a solar system wear out sooner. String inverters usually last 10–15 years, while microinverters and some hybrid inverters can last 20–25 years. Batteries in solar-plus-storage systems generally last 10–15 years. Racking and wiring can last the life of the system if properly installed.

How to Make Solar Panels Last Longer

  1. Choose quality equipment — Panels with strong warranties and low degradation rates.
  2. Use a reputable installer — Proper installation prevents most early failures.
  3. Keep panels clean — Rinse off dust, pollen, and debris a few times a year.
  4. Schedule inspections — Have the system checked periodically for damage or loose connections.
  5. Monitor output — Watch production data to catch drops in performance early.

When to Consider Replacement

Consider replacing panels if output drops well below the warranty guarantee, if panels are visibly cracked or delaminating, or if repeated repairs cost more than a new system. Because efficiency of new panels keeps improving, some owners upgrade after 25–30 years even if the old panels still work, to get more power from the same roof space.

Pro Tips

Pick panels with a low annual degradation rate and a strong 25-year warranty for the longest service life.

National Renewable Energy Laboratory

Rinse panels a few times a year to clear dust and pollen that reduce output.

U.S. Department of Energy

Budget for an inverter replacement around year 10–15, since it wears out faster than the panels.

EnergySage

Quick Facts

Most solar panels carry 25–30 year performance warranties and often keep producing power for 30–40 years.

Source: U.S. Department of Energy

Panels degrade about 0.5% per year on average, retaining roughly 87% of output after 25 years.

Source: National Renewable Energy Laboratory

Inverters typically last only 10–15 years, so they usually need replacing before the panels do.

Source: EnergySage

Sources

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