Solar energy| Solar Energy and Radiance |
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The sun's rays that reach the surface of the Earth represent around 10 000 times the world's energy needs. Our total energy needs could be covered with only 0.01% of the energy coming from the sun. In France, the average annual global radiance varies between 900 and 1 700 kWh/m2. This is why the site location choice is a fundemental factor during the planning of a photovoltaic installation. Solar radiance is made up of three elements: - direct solar radiance: 40% in the north of France and up to 60% in the south - diffused solar radiance, that comes from the sky but not directly from the sun (reflection on the clouds...): 40% in the south of France and up to 70% in the north - The "albedo" which is made up of the reflection of the sun's rays on the ground (snow, buildings, etc...). The energy that is finally received by a solar module is the sum of these three types of radiance. |