Solar power systems come standard with a 5-year, complete warranty and a 25-year warranty on the solar modules themselves. Most manufacturers guarantee that their solar modules will produce 80% of their initial production rating after 20 years. Degryse Electric offers an optional 10-year extended warranty on most residential and commercial inverters.
Reliability

Solar electric systems are a proven technology and are extremely reliable. Photovoltaic cells were originally developed for use in space, where repair is extremely expensive, if not impossible. Solar still powers nearly every satellite circling the earth because it operates reliably for long periods of time with virtually no maintenance.
Maintenance

Once installed, the solar electric system requires little or no maintenance (especially if no batteries are used), and will provide electricity cleanly and quietly for 25 to 40 years.