Abstract: The invention comprises a single unit which serves as the solar collector, heat storage area and the heat exchanger. A generally rectangular tank is provided with suitably heavy insulated walls at the bottom, ends and rear. One side, facing the sun is open and the opening extends into a portion of the top. The top is provided with a thickly insulated cover. The open side is provided with a heat collecting surface, the preferred angle being the latitude plus 10.degree.. The water is carried through suitable tubing which enters the tank through one end wall and then out through the same or another end wall. The tank is then filled with a suitable material having good heat storage and heat exchange properties. The best material is an eutectic salt having extremely high heat absorption and storage ability in direct contact with the container wall which is designed to absorb heat radiation, and in direct contact with the tubing to transfer the heat to the water passing through.

Abstract: The invention comprises a single unit which serves as the solar collector, heat storage area, and the heat exchanger. A generally rectangular tank is provided with suitably heavy insulated walls at the bottom, ends and rear. One side, facing the sun is open and the opening extends into a portion of the top. The top is provided with a thickly insulated cover. The open side is provided with a corrugated surface, the preferred angle being the latitude plus 10.degree.. The water is carried through suitable tubing which enters the tank through one end wall. The tubing is reentrantly bent in the tank to provide a plurality of lengths (4 shown) and then out through the same end wall but below the entrance. The tank is then filled with a suitable material having good heat storage and heat exchange properties.