Abstract: Solar water heating apparatus comprising a housing, apparatus disposed in the housing for receiving incident solar energy and for heating a first fluid thereby, heat exchanger apparatus disposed in the housing for contacting the heated first fluid and being operative to heat a second fluid; and apparatus for providing circulation of the first fluid through the receiving and heating apparatus and in thermal contact with the heat exchanger apparatus and wherein the first fluid is maintained at atmospheric pressure. A solar energy collector and concentrator useful in the above-described heating apparatus is also described and claimed.

Abstract: Non-focusing solar energy concentration apparatus comprising one or more solar energy absorbing surfaces defining a first area and solar energy transmissive material disposed adjacent the absorbing surfaces and defining an incident surface having a second area greater than the first area, the incident surface being arranged to receive incident radiation from the sun, the solar energy transmissive material also defining a second surface for transmitting radiation to the at least one absorbing surface, the transmissive material having an index of refraction and a configuration selected to provide total internal reflection at the incident surface of radiation incident on the incident surface within a predetermined azimuthal range.

Abstract: Non-focusing solar energy concentration apparatus comprising one or more solar energy absorbing surfaces defining a first area and solar energy transmissive material disposed adjacent the absorbing surfaces and defining an incident surface having a second area greater than the first area, the incident surface being arranged to receive incident radiation from the sun, the solar energy transmissive material also defining a second surface for transmitting radiation to the at least one absorbing surface, the transmissive material having an index of refraction and a configuration selected to provide total internal reflection at the incident surface of radiation incident on the incident surface within a predetermined azimuthal range.