Solar panel lifespan, degradation and warranties
Sources checked
Warranty length is not the date a panel stops working. A product warranty concerns defects; a performance warranty concerns the module's guaranteed output under stated terms. Actual service life depends on equipment condition and operating circumstances.
Distinguish gradual ageing from a fault
A progressive decline can be different from sudden damage, shading or an electrical failure. A module performance warranty does not guarantee the complete installation's annual generation, because weather, inverter operation and other losses also affect it.
The source cites SIEA's expectation of more than 30 years for panels and more than 20 years for a well-executed system. Those general expectations are not an individual product guarantee.
Keep evidence for a claim or replacement
Retain model and serial details, invoices, commissioning records, safe photographs and the applicable warranty document. Check the claim route and whether diagnosis, transport, removal and reinstallation are covered.
Before replacing older modules, obtain a condition and compatibility assessment. The remaining roof life, mounting, inverter and availability of suitable replacements affect the decision alongside degradation.