Eco News

Solar cells convert sunlight directly into electricity. Anteriorly solar cells were often used for personal computers and watches. They are made of semiconductor materials, similar with those used in computers.
When light is absorbed by these materials, solar energy is degraded in atoms, the flow of electrons produces electricity.

This process of light conversion in electricity is called the photovoltaic effect. Therefore photovoltaic cells not be confused with other solar systems. They are marked with the symbol PV. Photovoltaic panels are usually combined into modules that hold about 40 cells. A greater number of these modular units can form a few meters.

These panels can be mounted on a device for tracking the sun to enable them to capture the most sunlight during the day. More interconnected panels can provide enough power for a household. For electrical equipment of high power for industrial applications or public utility are necessary hundred of panels that will be interconnected to form a single, large PV system.

Solar cells use layers of semiconductor materials only a few microns bigness. The technology leap has made it possible for these to be incorporate in facades, roofs, etc.

Some solar cells are designed to work with concentrated sunlight. These cells are constructed based on focus using a lens of solar light. This approach has both advantages and disadvantages compared with flat panels.

Performance of photovoltaic cells is measured in electric current produce. For this reason, solar photovoltaic panels have in the best case a 15% efficient. An efficient so small on a panel leads to a large number of panels and therefore means higher costs. Improve the solar cells is the main objective of the photovoltaic industry.

The first cell had 4% efficient and have been produced in 1950. Today the third generation of photovoltaic panels containing cells an efficient 20% and it was hoped that in a few years to grow it.