Abstract: A combined solar water heating device and storage tank for low cost solar hot water heaters is disclosed, consisting of an insulated open-topped tank in which is introduced a volume of water at atmospheric pressure to be heated by solar radiation entering through the open top of the tank. A transparent cover extends over the open top of the tank and acts to trap long wavelength reradiation from the heated water, such as to insulate the volume of heated water by preventing radiant heat loss. A pivotal reflector-insulator panel is also positioned over the tank opening which is alternately placed in an open position, in which it allows the entrance of solar radiation which is maximized by a reflectorized undersurface of the panel; and a closed position, in which it serves to insulate the heated water. The position of the pivotal reflector-insulator panel is optionally controlled by a radiation sensor to open and close the panel under varying conditions of solar radiation.

Abstract: A greenhouse construction and method of growing plants in cold climates employing a water layer defining in part a growing environment which transmits solar radiation into the interior of an enclosure constituting the growing environment. The water layer acts to absorb longer wavelength infrared portions of the solar spectrum preventing overheating of the greenhouse interior during cold and warm weather seasons, with the resultant heating of the water in the layer allowing it to act as a thermal storage medium during cold weather seasons. At the same time, the water layer transmits the photosynthetic shorter wavelengths of the solar spectrum to support plant growth within the greenhouse. The water layer is disposed in a ceiling structure, consisting of spaced transparent sheet layers combined with a pivotal reflector-insulator panel acting to cover the water layer during nighttime or other periods when solar radiation is absent or minimal.