How long does an industrial solar system last?

The technical service life of a solar system is 25–30 years. The manufacturers’ performance warranty for the modules typically runs for 25–30 years, with a guaranteed annual degradation: for modern monocrystalline modules this is 0.4–0.55%/year, meaning that even in year 25 around 85% of the nominal power is available. The module is the longest-lived component of the system. The service life of inverters is considerably shorter, typically 10–15 years, so the financial model of the investment must include the cost of at least one inverter replacement — its absence is often noticeable when comparing offers, and it materially distorts the payback calculation. The mounting structure (aluminum, galvanized steel) lasts as long as the modules. The practical service life is usually ended not by the aging of the modules, but by changes in technology and in the site’s energy demand over time. That is why it is worth considering at the design stage whether the system can later be expanded or supplemented with battery storage — doing so afterwards is considerably more expensive.