Photovoltaic describes technology that converts sunlight directly into electricity.

Photovoltaic panels, often called solar panels, contain special materials that react when sunlight hits them. Inside each panel are layers of silicon crystals that release electrons when struck by photons (particles of light). These moving electrons create an electric current, which can power everything from calculators to entire houses.

You've probably seen photovoltaic panels on rooftops or in solar farms. They're the dark blue or black rectangles that seem to do nothing but sit in the sun. Yet those panels are performing an almost magical trick: turning pure sunlight into usable power without any moving parts, fuel, or air pollution.

The technology keeps improving. Modern photovoltaic cells can convert about 20% of the sunlight that hits them into electricity, and scientists are working to make them even more efficient. Some spacecraft rely entirely on photovoltaic panels for power, and many remote areas use them where running electrical wires would be impractical or impossible.