A solar system comes with an individual equipment warranty for a certain period of time which includes solar panels, inverter, battery and even installation.
Say Solar panels, usually, come with a performance warranty of a maximum of 25 years which covers panels' power output for a certain period of years. For instance, a panel may still produce 90% of its rated output after 10 years and 80% after 25 years, according to a power output warranty given by manufacturer. It may also be stated as a linear warranty in one figure, for example, 85% after 25 years.
