25-year limited power warranty (typically 10 years at 90% power output and 25 years at 80% power output). Workmanship and materials warranty of one or two years.
For instance, after 10 years, a panel might guarantee 90% of its original efficiency, and after 25 years, 80% 1. This type of warranty is crucial as it assures buyers that their investment will remain efficient over time. Product warranties are separate from performance warranties and cover defects in materials or workmanship.
How long does a solar panel's power warranty last?
Most solar panel power warranties nowadays offer linear degradation, meaning a 0.7% output loss per year. However, some manufacturers like SunPower offer a much higher output guarantee after 25 years. In the past, power warranties were stepped, guaranteeing 90% output after 10 years and 80% output after 25 years.
If you're a homeowner in the UK, consider this: Your solar panel system, without the right protection, might end up being a liability instead of an asset. By choosing a warranty that ensures the product's quality and long-term performance, you're safeguarding your investment from manufacturer defects and inevitable wear and tear over time.
The warranty typically covers the solar panels themselves, as well as the inverters and other components of the solar panel system. The warranty may also cover the labor and materials used in the installation of the panels, as well as any defects or issues that may arise with the panels during the warranty period.
A power warranty for solar panels states the expected output of a panel after certain periods of time (eg 5 years, 10 years, 20 years). All solar panels are affected by gradual degradation in efficiency, so the output will decrease. If the panels do not perform as promised, you may be able to get them replaced or repaired - but some power warranties do not cover defects.
25-year limited power warranty (typically 10 years at 90% power output and 25 years at 80% power output). Workmanship and materials warranty of one or two years. Batteries (non-grid systems / hybrids) roughly 5-15 years. Inverter (s) warranty of between 5-10 years.