Parabolic dish collector, one or more parabolic dishes concentrate solar energy at a single focal point. The shape of a parabola means that incoming light rays which are parallel to the dish's axis will be reflected toward the focus, no matter where on the dish they arrive. Light from the sun arrives at the earth's surface almost completely parallel. So the dish is aligned with its axis pointing at the sun, allowing almost all incoming radiation to be reflected towards the focal point of the dish. Most losses in such collectors are due to imperfections in the parabolic shape and imperfect reflection.
Losses due to atmospheric scattering are generally minimal. However, on a hazy or foggy day, light is diffused in all directions Trough the atmosphere, which reduces the efficiency of a parabolic dish significantly.