Warranties vary depending upon what type the solar system that you invest in and the way you choose to go solar.
If you lease or enter a power purchase agreement (PPA) your system will be worry free for up to 20 years. The installation and any future repairs are fully covered for the life of the lease or PPA. The system is also insured against damage from weather and acts of God.
If you purchase your new solar panel system; most systems come with a 25 year power production guarantee on the panels and anywhere from a 10 year to a 25 year guarantee on the inverters. Labor is typically covered for 10 years.