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PerformanceUp to date · Jan 15, 2026

Degradation Rate

The annual decrease in solar panel efficiency. Modern panels typically degrade 0.3-0.5% per year.

Why It Matters

Over 25 years, degradation determines total lifetime production. A panel with 0.25% degradation produces about 6% more energy over its life than one at 0.5%.

Real-World Example

A 400W panel with 0.5% annual degradation will produce about 350W in year 25 — still generating 87.5% of its original output.

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