How Do Solar Panels Work?

Solar panels collect solar radiation from the Sun and actively convert that energy to electricity.

Solar panels are comprised of several individual solar cells, which function similarly to large semiconductors and utilise a large-area p-n junction diode. When the solar cells are exposed to sunlight, the p-n junction diodes convert the energy from sunlight into usable electrical energy.

The energy generated from photons striking the surface of the solar panel allows electrons to be knocked out of their orbits and released and electric fields in the solar cells pull these free electrons in a directional current from which metal contacts in the solar cell can generate electricity. The more solar cells in a solar panel and the higher the quality of the solar cells, the more total electrical output the solar panel can produce. The conversion of sunlight to usable electrical energy has been dubbed the photovoltaic effect.

The photovoltaic effect arises from the properties of the p-n junction diode. There are no moving parts in a solar panel.

Solar Insolation and Solar Panel Efficiency

Solar Insolation is a measure of how much solar radiation a given solar panel or surface receives. The greater the insolation, the more solar energy can be converted to electricity by the solar panel.

Other factors that affect the output of solar panels are weather conditions, shade caused by obstructions to direct sunlight and the angle and position at which the solar panel is installed. Solar panels function best when placed in direct sunlight, away from obstructions that might cast shade and in areas with high regional solar-insolation ratings.

Solar-panel efficiency can be optimised by using dynamic mounts that follow the position of the sun in the sky and rotate the solar panel to get the maximum amount of direct exposure during the day as possible.