Patent ID: 7823582

Claim:
A solar collector comprising: an absorber having an upper surface for receiving solar radiation and a lower surface, the absorber adapted for circulating a heat transfer fluid therethrough; a bottom portion having: (a) an upper surface substantially facing the lower surface of the absorber; and (b) an air inlet and an air outlet disposed therethrough; a venting channel between the lower surface of the absorber and the upper surface of the bottom portion; wherein the air inlet and the air outlet are in communication with the venting channel and at substantially opposite ends thereof; wherein the lower surface of the absorber is radiatively coupled to the upper surface of the bottom portion; wherein the radiatively coupled surfaces are treated to have high emissivity to enhance radiative heat transfer from the lower surface of the absorber to the upper surface of the bottom portion, such that surface area for convective heat transfer to air in the venting channel is increased; wherein passive air flow from the inlet, through the venting channel, and out the outlet removes heat from the venting channel.