Photovoltaic energy systems definition

Adsense kodları buraya gelecek...

Photovoltaics is the direct conversion of radiant energy such as sunlight into electricity through quantum mechanical processes. Photovoltaics is also known as 'solar electric power' or 'solar power', though the latter term fails to adequately distinguish photovoltaics from other technologies that make use of solar energy, such as solar hot water, or solar thermal electricity generation.
The photovoltaic effect - the process by which sunlight is converted to electricity - was first noted by Edmund Becquerel in 1839.
The principle component of a photovoltaic system is the photovoltaic cell, or solar cell. Commercial solar cells are typically made from silicon, though other materials such as gallium arsenide, and even more exotic combinations are also used, particularly in high efficiency laboratory devices, or cells meant for satellite and space applications, where capital cost is small compared to the cost of sending material into orbit. The common feature of the materials that can be used to make a solar cell is that they are semiconductors.
Semiconductors can have a high electrical resistance, but be put into a lower resistance mode when under the correct conditions. Another way of describing this is that there are not many free electrons in a semiconductor, but a small amount of energy can release the electrons from the atoms they are bonded to.

Photovoltaic energy

Photovoltaics research institutes
There are many research institutions and departments at universities around the world who are active in the field of photovoltaic. Countries which are particularly active in the field of photovoltaics are Germany, Japan, Australia, China, and the USA.
Some universities and institutes which have a photovoltaics research department.
• Centre for Photovoltaic Engineering at The University of New South Wales
• Institut für Solare Energiesysteme ISE at the Fraunhofer Institute
• Centre for Sustainable Energy Systems at the Australian National University
• National Renewable Energy Laboratory NREL
• Advanced Energy Systems at Helsinki University of Technology