Glossary
Inverter
The inverter is the device that converts the direct current (DC) generated by solar panels into the alternating current (AC) used by your appliances and the grid. There are two families: the string inverter (one central unit for all panels) and microinverters (one per panel).
What an inverter is
Panels produce electricity as direct current. Your fridge, your AC and the grid run on alternating current. The inverter makes that conversion and also decides how much to draw from the panels at every moment to maximize output. Without an inverter, panels are just glass on the roof.
A string inverter is a single box, usually mounted next to the electrical panel, fed by panels wired in series. A microinverter is a small inverter under each panel, so each one works independently.
Why it matters in Florida
The inverter is the component most likely to fail over the life of the system, because it is electronics working outdoors in heat and humidity. Florida is harsher on it than most of the country. Its warranty is usually shorter than the panels’, so ask how many years it covers and who pays the labor for a replacement.
The inverter also determines how much shading hurts you. On a string, one shaded panel drags the others down. With microinverters, each panel performs on its own.
Common mistake
Comparing proposals by panel brand only and ignoring which inverter they include. Two systems with the same panels and a different inverter can produce different amounts of kWh and carry very different warranties. Get the brand, model and warranty years in writing. In string inverters vs microinverters we tell you when each one makes sense.
Full guide: String inverters vs microinverters: which one belongs on your roof →
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