How Solar Power Works

The sun’s energy can be converted into useful electricity in several ways. The two main methods are through photovoltaics (solar cells) and the concentration of solar power, but there are also numerous experimental technologies that are on the verge of becoming commercially applicable.

Photovoltaic (PV) technology is the use of solar cells to convert the sun’s light into direct current using the photoelectric effect. This effect is the phenomenon in which electrons are emitted from matter after the absorption of electromagnetic radiation such as x-rays or visible light.  When sunlight hits the solar panel, light is absorbed by the silicon and electrons are knocked loose from their atoms, allowing them to flow freely through the silicon to produce electricity.

PV panels contain an interconnected assembly of PV cells, also called solar cells. An installation on a rooftop or as a ground-mounted collection system is called a photovoltaic array and consists of multiple PV panels. Each cell on a panel is wired to connect to other cells and each panel is wired to connect to the other panels in an array. The array contains multiple panels, an inverter (which converts direct current to alternating current) and interconnection wiring to connect the system to the power grid.

PV has numerous applications from powering a calculator with a single solar cell, to powering off-grid homes with a few PV panels, to commercial-scale photovoltaic arrays composed of many connected solar panels.