Project panel output decline over the system lifetime and against warranty terms.
At 0.5 per cent annual degradation panels retain about 88 per cent of output after 25 years, comfortably above a typical 85 per cent warranty floor. Degradation compounds rather than accumulating linearly. Warranty claims turn on measured output against the guaranteed curve, which makes accurate first-year baseline data valuable.
Solar Degradation
Remaining capacity = (1 − degradation rate)^years
Remaining capacity = (1 − degradation rate)^years At 0.5 per cent annual degradation panels retain about 88 per cent of output after 25 years, comfortably above a typical 85 per cent warranty floor. Degradation compounds rather than accumulating linearly.
Warranty claims turn on measured output against the guaranteed curve, which makes accurate first-year baseline data valuable.
This calculator takes 4 inputs: First year generation, Annual degradation rate, Years elapsed, Warranted output at end of term. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.