Solar Information Solar cells (also called photovoltaics) absorb sunlight and convert it directly to electricity. Solar cells are very thin (about 1/100th of an inch thick). Most are rectangular or circular wafers made of silicon (sand), but some consist of a thin film that is mounted on glass or thin metal. When sunlight hits the cell, electrons are released. The electrons then flow onto wires, forming direct current (DC), which is the same kind of current that flows from a battery. A number of cells (usually 20 or more) or a film can be mounted within a frame under a transparent glass or plastic covering to form a module. Modules can be connected to other modules to form an array. Solar modules can be free-standing units, but there are also building-integrated solar products, such as solar roof shingles. The Two Types of Photovoltaic Systems Economics and Future Prospects Environmental Impacts Four Myths about Solar Energy in Rhode Island Is Your Building a Good Place for a Solar System? Glossary of Solar Terms For Further Information