How long does a solar inverter last?
Updated August 2026
A solar inverter lasts 10 to 15 years as a string inverter and 20 to 25 years as a microinverter. The inverter converts the panels' DC into the AC your home uses, and it works hot and hard every sunlit hour, which is why it wears out well before the 25-to-30-year panels above it. Plan on a string inverter needing one replacement during the life of the array. Microinverters, one bolted under each panel, and power optimizers spread the load and run cooler, so they last roughly twice as long and are warrantied to about 25 years. Heat is the constant enemy. A replacement runs $1,500–3,000.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| String inverter | 10–15 years | One central box; the classic mid-life replacement |
| Microinverter | 20–25 years | One per panel, cooler duty, warrantied to about 25 years |
| Power optimizer plus inverter | 15–25 years | Optimizers last long; the central unit less so |
| Hybrid / battery inverter | 10–15 years | More electronics and heat; ages like a string unit |
| Mounted in direct sun or heat | Cut 2–5 years | High temperatures are the top life-shortener |
| Mounted in shade with airflow | Top of range | Cooler running is the cheapest life extension |
Signs yours is near the end
- A fault light or error code on the inverter, or the display going blank
- System production dropping to zero while the panels sit in full sun
- The monitoring app reporting frequent dropouts or reduced output
- A loud fan, buzzing, or an inverter running very hot to the touch
- Corrosion, water intrusion, or scorching around the enclosure
- An inverter past 10–12 years starting to fault more often
How to add years
An inverter mostly asks to be left cool and watched. Mount or shade it out of direct afternoon sun and keep its vents and fan clear, since the heat it generates is the single biggest thing that shortens its life. Watch the monitoring app so a fault is caught in days, not the months of lost production it can otherwise cost. Because a string inverter is expected to fail once in 25 years, treat its replacement as scheduled, not surprise, maintenance, and when it starts faulting, weigh repair against a straight swap, often to a newer, more efficient model.
What it costs to replace: plan on $1,500–3,000 for a string inverter ($150–300 per microinverter if one fails). Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
OnOtto tracks your inverter checks age and service history, and warns you before end of life instead of after the flood.
Track your home's systems, free for 30 daysFrequently asked questions
Why does the inverter fail before the solar panels?
Because it does the hard work. Panels are passive glass and silicon with nothing to wear out, so they simply fade over 25 to 30 years. The inverter is packed with capacitors, transistors, and a cooling fan, all running hot every hour the sun shines and cycling on and off daily. That constant thermal stress ages electronics far faster than sunlight ages a panel. A 10-to-15-year string inverter lifespan against 25-to-30-year panels is exactly why one inverter replacement is built into most solar budgets.
Do microinverters last longer than a string inverter?
Yes, by roughly double. A central string inverter carries the whole array's load in one hot box and typically lasts 10 to 15 years. Microinverters split that work across many small units, one under each panel, so each runs cooler and lighter and lasts 20 to 25 years, usually with a matching 25-year warranty. The trade-off is cost and access: microinverters run more upfront, and replacing a failed one means getting on the roof, though it only takes the affected panel offline instead of the whole system.
What are the signs a solar inverter is failing?
A fault code or dark display on the unit, and production dropping to zero even though the panels sit in bright sun, are the clearest signs. The monitoring app may show repeated dropouts or a steady decline before the unit quits entirely. Physically, a failing inverter often runs hot, buzzes, or shows a loud fan, and may have corrosion or scorch marks. Since a dead inverter can silently cost weeks of generation, treat any persistent fault or a multi-day production gap as a service call, not a wait.