Abstract: The invention relates to a solar energy pick-up employing a stream of water, comprising an inclined surface on which substantially regular obstacles are arranged against the flow of the water arriving at the top of the inclined surface and collected at the bottom thereof, wherein the walls of the obstacles are reflecting and define channels for the passage of the water, whose depth is greater than five times their width.

Abstract: Heater comprises a container divided into upper and lower chambers by a perforated plate. The container is connected to receive heated liquid from a solar collector and deliver it to radiators or the like. The container is equipped with an electrical heating coil for further heating the liquid when the solar heat supply is inadequate.