Photovoltaics (PV) is a technology that converts light energy into electricity. PV produces electricity from a clean, renewable source without noise or air pollution. The basic unit of a PV system is the solar cell, a small, square-shaped semiconductor made from silicon or other conductive materials. Approximately 40 solar cells make up a solar module (more commonly known as a “panel”). Panels grouped together make up an array. Finally, arrays grouped together form a solar system. A typical PV system has a PV array(s) and a control center containing a DC to AC inverter. Alternately, some systems have micro-inverters attached to each panel. Some people add batteries to their system in order to store the unit’s output for use at night or as a backup in case of a power outage.
Solar panels can be mounted at a fixed angle facing south, or they can be mounted on a tracking device that follows the sun, allowing them to capture more sunlight than fixed angle systems. For utility or industrial-scale applications, hundreds of solar arrays are interconnected to form a large PV system, also known as a solar farm.