Translations:Chauffe eau solaire/43/en

In the middle of winter, in France, the sun has a zenith at 30° with the horizon, this is its maximum height. In summer, at the same latitudes, it rises to 60°. Ideally, the panels will be installed perpendicularly to the winter sun rays, so 90°+30°=120°. They form a 120° angle with the horizon, south oriented (see scheme) . Otherwise, to limit the losses, one can put them vertically against a wall, it is more interesting and less dangerous than on roofs.