The working life of a solar panel should be in excess of 25 years and many panels come with a 25 year performance warranty. There are several warranty types to consider.
Panel warranty from manufacturer
Most panel warranties have two parts, a construction/materials warranty and a power output warranty. The first covers the actual manufacturing quality of the panel and warrants the panels to be free of manufacturing and materials defects for a given time, usually ten years or so, but some manufacturers provide manufacturing warranties up to 25 years or more.
The performance warranty covers the actual panel power output and is given in the form of a percentage after a certain number of years. For example, a power output warranty might state that a panel will still produce 90% of its rated output after ten years and 80% after 25 years. Or it might be stated as a linear warranty with just one figure, say 85% after 25 years.
Any high-quality panel would be expected to still produce at least 80% of its original rating after 25 years. Under Australian consumer law importers are responsible for manufacturers’ warranties, so it’s important to know who your importer is because sending the panels back to the country of manufacture would be impractical.
To guard against this issue some manufacturers provide prepaid insurance at no extra cost, which ensures the warranty will be honoured even if the manufacturer goes out of business. Others provide comprehensive insurance, at an extra cost, which covers just about everything from theft to failure for a period of a few years.
WARNING: Remember to read the fine print on all insurance policies, including excesses. If the manufacturer pays for their product insurance annually, rather than it being prepaid in full, the insurance may lapse after the company becomes insolvent, meaning you can lose both warranty and insurance coverage.
Inverter warranty
A good quality inverter should last at least ten years, if installed properly, and given no accidents such as lightning strikes. Lifespan will vary, depending on a number of factors including ambient temperature, mains grid voltage and mains power quality. Many large electrical spikes, caused by large loads like electric motors, can eventually cause damage to even the best equipment.
Other factors that can affect lifespan are dust, heat, ventilation and pests or vermin such as mice or ants. To guard against the cost of an early failure look for long inverter warranties. Five years is a suggested minimum. A five year warranty with the option of buying an extra five year warranty is often available and can be good value and offer peace of mind.
Installation warranty
Another important aspect of the warranties is the installation or workmanship warranty. This is the part of the warranty that is the responsibility of the system installer and covers their workmanship as opposed to the panels or inverters within the system. It is also important to understand whether the installer or solar retailer will assist in enacting any manufacturer warranties should a fault occur with a major system component.
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