Silicon solar cells catch sunlight and turn it into electricity. Made from purified sand, solar cells use the same semiconductor materials used in computers, but they can absorb light to create the photovoltaic (PV) effect. We call this solar electric power or just “solar” at Sungevity, but you’ll also hear it referred to as solar PV, or just PV.
Back to the science. All the fun stuff happens near the top surface of the solar cell, which faces the sun. There are two layers of semiconductor material, a positive and a negative, making a small electric field.
When light falls on the surface of the cell, some of the silicon’s electrons are knocked free by the photons, the bundles of energy that arrive from the sun. The electric field then drives these electrons from negative to positive as a flow of electric current. This current travels down your down wires in direct current or DC and enters the inverter which converts it into alternating current or AC, the kind of electricity you use in your home.
The solar cells have fine metal wires on their surface to collect these electrons and convert over 15% of the photons’ energy directly into electricity. Clean, fuel-free electricity directly from sunlight!
The solar panels (also called solar modules) are covered in anti-reflective glass and sealed to protect the cells from the atmosphere. As there are no moving parts and only the glass and aluminum frames are exposed to the elements, the panels last for decades.
These panels are themselves combined in a string of panels to create a solar array. Sungevity works in strings of 8 panels to create systems for your energy needs. After Sungevity mounts them on sturdy frames fit to your roof, a professional contractor wires the solar panels to your inverter, your home and the grid.
As easy as that, you have yourself a home solar electric system – ready to save electricity, money and the planet.