How solar panels work
A solar panel is a sheet of photovoltaic (PV) cells, usually made of silicon. When sunlight hits a cell, it knocks electrons loose, and the cell’s built-in electric field pushes them in one direction. That flow of electrons is electricity.
From the roof to your outlet
- Panels produce direct current (DC) whenever light hits them.
- An inverter converts DC into the alternating current (AC) your home uses. Some systems use one central inverter; others put a small “microinverter” on each panel.
- Your home uses the power first. Anything left over can charge a battery or flow back to the grid.
- Your meter tracks it. Depending on your utility’s rules, exported power may earn a credit on your bill.
What affects how much you get
- Sun hours — where you live and the time of year.
- Orientation and tilt — in the Northern Hemisphere, south-facing roofs usually produce the most.
- Shade — even partial shade on one panel can reduce output, which is one reason microinverters and optimizers exist.
- Temperature — panels are actually a little less efficient when hot.
Coming next
Batteries, net metering, and how to estimate whether solar pays off for your home.