Trends and benefits of photovoltaic energy

Practical benefits

This technology enables the use of renewable energy from the sun. There are twotypes of solar energy:

• Thermal energy captured through an exchange between circulating fluid exposed to the sun and a load circuit (accumulation tank or heat pump).
• Photovoltaic energy, which uses the principle of the photovoltaic cell discovered by Edmond Becquerel in 1839 to produce electrical power.

It is particularly beneficial to use solar radiation reaching the earth since:

• This radiation remains stable (to within 10%) on average from one year to the next;
• At ground level, it supplies an average of 1000 Wh/m² per day although this depends on the following principal criteria

   - The latitude
   - The angle of the surface and the direction faced
   - The degree of pollution
   - The time of year
   - The thickness of the cloud layer
   - The time of day
   - The shade
This radiation varies from 870 Wh/m² per day in the North of France to 1890 Wh/m² per day in Corsica (and up to 3125 Wh/m² per day in the Sahara).

Environmental benefits

By using solar energy, it is possible to reduce consumption of “fossil” fuels which are the likely cause of global warming and atmospheric pollution.
This contributes to sustainable development and is also in keeping with the policies of the European Council, which passed a decree in March 2007 setting the following targets to be met by 2020:

• Reduction of greenhouse emissions by 20%
• Reduction of energy consumption by 20%
• 20% renewable energy as a proportion of total energy consumption