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Operating principle

Exploit the energy-producing potential of flat roofs

Peaking capacity

A 1 kWp* installation produces about 1,000 kWh a year in France.
Photovoltaic production varies according to:
  • Geographical sunshine levels
  • The slope of the modules
  • The orientation of the building and the modules
  • Whether or not the site is liable to dirt accumulation…
*Peaking capacity (p): theoretical instantaneous power subject to conditions

Photovoltaic energy is the result of the direct transformation of the sunlight into electric power by means of cells usually made of silicon, a semiconductor material. To obtain sufficient power, photovoltaic cells are linked to each other to make up a module or solar panel.

Depending on the power required, a number of panels may be assembled to constitute a "photovoltaic array". Connected directly to the receiver, the solar panel operates "directly from the sun", which means that the electric power supplied to the receiver depends on the power of the sunlight. It therefore generates most power when the sun is at its highest and none at night.

In practical terms, the direct current produced by the photovoltaic modules is changed into alternating current by one or more inverters before being injected into the distribution grid, the energy produced by the photovoltaic power plant is sold to the utility company at a preferential rate fixed for 20 years.

Naturally, roofs provide an ideal location for photovoltaic power plants.

Principe de l’étanchéité photovoltaïque