Solar panel degradation rates: what to expect

All solar panels degrade over time — it's unavoidable physics. The question isn't whether your panels are degrading, but whether they're degrading faster than expected. Published research shows median degradation rates of 0.5–0.8% per year, but real-world rates vary significantly by climate, panel quality, and installation conditions.

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Natural panel degradation

All solar panels lose efficiency over time at roughly 0.5–0.8% per year. Accelerated in extreme heat or poorly manufactured panels.

Typical loss: 315%Detection: monitoring

Self-check tip:

Compare current annual production to your system's first-year output. A decline beyond 1% per year may indicate accelerated degradation.

Is your system affected?

Use our free Solar Loss Checker to estimate how much energy your system may be losing.

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Based on conservative solar performance modelling and published degradation data

NRELIEA-PVPSSunSpecPVsyst+ published research

Updated April 2026 · Structured performance modelling

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