photovoltaic cells for converting solar radiation directly into electricity, using the so-called "photovoltaic effect" based on the properties of some conductive materials appropriate treatment (including the silicon, an element widely in nature), to directly generate electricity when hit by sunlight. A photovoltaic cell is exposed to solar radiation acts as a current source with a characteristic voltage / current depends basically on the intensity of solar radiation, temperature and the surface.
It is generally a square area of \u200b\u200babout 100 cm2, behaves like a tiny battery, resulting in the conditions of typical Italian sunshine, a current of 3 A (Amps) with a voltage of 0.5 V (volts), then a power of 1.5 W (Watt) .
Monocrystalline cells: are produced by cutting a single crystal bar. The main advantage is a high efficiency (up to 16%). This type of cells is very expensive because of the complicated production process. Monocrystalline cells are usually characterized by a homogeneous blue color.
pole cells (multi-) crystalline: they are cast into blocks and then cut into disks. The yield is lower (10 ° 12%), but also the price. This type of cells can be recognized from a design easily distinguishable (because of the different crystal contents). Cells
amorphous: is produced by cathodic deposition of silicon atoms on a glass plate. This type of cell has a lower yield (ca. 4 ¸ 8%), but also adapts to the case of diffuse radiation (clouds, etc.).. The cells so produced are recognizable by a distinctive dark color, also can be made in any geometric shape (circular shapes are possible, octagonal, irregular, and even convex).
types of solar cells: 1) monocrystalline cells, 2) multi-cell poly-crystal, 3) amorphous cells.
from the photovoltaic cell
The scheme
single solar cell, measuring about 10 X 10cm, the device is the primary basis for any mismatch losses.
A PV module consists of a set of solar cells linked together to provide an electrical output (per module) on average between 50 and 100 W.
To increase the power supply is necessary to connect several modules: more modules form a panel and, similarly, more panels form a string.
photovoltaic modules convert light energy into direct current electricity in "real time", ie the production of electricity is simultaneously with the capture of solar energy.
For these and other reasons, a photovoltaic solar generator are needed in addition to other components of the photovoltaic system. The plant types
The photovoltaic system is the set of mechanical, electrical and electronic systems that capture solar energy, transform it into electricity, until it becomes available for use by the user.
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