60/641; 126/270; 126/271; 60/659 F03G 7/02; F24J 3/02 60/641; 126/270,271 5124 Durham [76] Inventor: William R. Powell, 1940 Rd. W. Court, Columbia, Md. 21044 [22] Filed: Aug. 19, 1974 [21] Appl. No.: 498,529 [52] U.S. CL. [51] Int. Cl. [58] Field of Search [56] References Cited UNITED STATES PATENTS 3,869,199 3/1975 Cummings 126/270 X A receiver for collecting solar energy at high temperatures with low reradiation losses, the invention comprises in a preferred embodiment an insulated cavity absorber wherein a temperature gradient exists from the receiving end of the absorber toward the closed end thereof. The closed end exists at a higher temperature than the receiving end due to the cooling effect of a flow of fluid directed into contact with the walls of the absorber from the receiving end toward the closed end, the fluid being additionally utilized to extract heat from the absorber for utilization thereof. 18 Claims, 6 Drawing Figures |