In order to convert solar energy into electricity, semi-conductors are used, which are basically solar panels capable of generating small currents and voltage. In order to achieve stronger currents, the panels are connected in serial or parallel mode to create photovoltaic modules, which are in turn also connected in serial or parallel mode to obtain the voltage and current required.

For the sake of efficiency, the photovoltaic panels should be inclined at an angle of 15� in summer and 60� in winter. The system offers optimum performance when capturing sun rays that hit the panels at right angles. A photovoltaic module can also generate energy on cloudy days, although its performance is somewhat lower than on sunny days.

Applications of solar energy
Solar energy is inexhaustible and easily accumulated. When the sky is clear and the sunrays fall directly on to the panels, a daily average of 870 watts per square meter in electromagnetic radiation can be generated. This is equivalent to the daily output of a household in a developed country.
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One of the most common uses of this type of electricity is in geographically isolated areas which do not have access to the electricity grid, such as islands, rural zones or country houses. In these areas, the hours of sunlight are harnesses to recharge batteries which are then used through the night.

The other system that is increasing in popularity is photovoltaic energy connected to the grid. This has been regulated in Spain and its main aim is to increase the production of renewable electricity without contaminating the environment.

Did you know...?
-Countries such as Germany or Sweden use a major amount of solar-generated electricity in spite of having relatively few hours of sunlight.
-Solar panels have provided energy to satellites and spaceships (such as MIR) for over a quarter of a century.
- Seville has been incorporating into the local grid�a large amount of green electricity produced by the 22 photovoltaic installations located throughout the city, which places the Andalusian conurbation among the leading users of renewable electricity in Europe.
-The Hemau Power Station in Bavaria has four times more photovoltaic power than that generated by any Spanish plant. With 32,740 photovoltaic panels, producing a total of 4 MW, it is the largest such plant in the world.