Electricity From Sunlight

The capture and conversion of sunlight to electricity is a rapidly evolving area of technology that is spawning scores of start-up companies pursuing innovative products. This is particularly true of the direct sunlight-to-electricity conversion technologies suited to distributed small-scale applications. The field of concentrating photovoltaics is a particularly active area of research and development.

• Direct conversion of sunlight to electricity
  • Photovoltaics
  • Concentrating photovoltaics (CPV)
  • Nanoantennas
• Indirect conversion of sunlight to electricity using heat
  • Solar thermal power (CSP)

Efficiency

An electric solar energy system's efficiency is the fraction of light energy falling on it that is converted to electrical energy, when it is connected to an electrical circuit. Since the flux of sunlight at sea-level on a clear day is approximately 1000 watts per square meter, the efficiency of a photovoltaic panel can be measured, roughly, by orienting it perpendicular to the rays of the mid-day sun and dividing the output power, in watts, by one thousand times the area of the panel, in square meters.