Photovoltaics

Photovoltaics or PV for short is a solar power technology that uses solar photovoltaic arrays or solar cells to provide electricity for human activities. Photovoltaics is also the field of study relating to this technology.

Solar cells produce direct current electricity from the sun’s rays, which can be used to power equipment or to recharge a battery. Many pocket calculators incorporate a solar cell.

When more power is required than a single cell can deliver, cells are generally grouped together to form “PV modules” that may in turn be arranged in “solar arrays” which are sometimes ambiguously referred to as solar panels. Such solar arrays have been used to power orbiting satellites and other spacecraft and in remote areas as a source of power for applications such as roadside emergency telephones, remote sensing, and cathodic protection of pipelines. The continual decline of manufacturing costs (dropping at 3 to 5% a year in recent years) is expanding the range of cost-effective uses including roadsigns, home power generation and even grid-connected electricity generation.

Large-scale incentive programs, offering financial incentives like the ability to sell excess electricity back to the public grid ("feed-in"), have greatly accelerated the pace of solar PV installations in Spain, Germany, Japan, the United States, Australia, South Korea, Italy, Greece, France, China and other countries.