Solar energy collector

• US 4,368,725 A
• Filed: 11/07/1977
• Issued: 01/18/1983
• Est. Priority Date: 11/11/1977
• Status: Expired due to Term

• Current Assignee: Michael Mcclintock
• Original Assignee: Michael Mcclintock
• Inventors: McClintock, Michael
• Primary Examiner(s): Yeung, James C.
• Application Number:
  US05/849,521
• Time in Patent Office: 1,898 Days
• Field of Search: 126/271, 126/270, 126/432, 126/449, 126/445, 126/446, 126/417, 126/450, 237/1 A, 165/171, 165/168, 356/74, 350/258, 350/259, 350/260, 350/263, 350/261, 350/262, 350/264, 350/265
• US Class Current: 126/595
• CPC Class Codes: F24S 10/503 having conduits formed by paired plates, only one of which is plane
• CPC Class Codes: F24S 20/63 in the form of windows
• CPC Class Codes: F24S 50/80 for controlling collection or absorption of solar radiation
• CPC Class Codes: F24S 80/20 Working fluids specially adapted for solar heat collectors
• CPC Class Codes: Y02B 10/20 Solar thermal
• CPC Class Codes: Y02E 10/44 Heat exchange systems

Abstract

A solar window which can alternatively act either as a passive solar heat collector or an active solar heat collector. A substantially transparent pair of panels are mounted in opposed position to each other and define a chamber therebetween. When it is desired to admit solar energy to the structure in which the window is mounted, air is permitted to be retained in the chamber and sunlight to pass through the window to thus heat the interior of the structure. When heat is not required in the structure, a second fluid which may be an optically dense solar energy absorbent or reflective fluid is passed through the chamber so as to respectively absorb or reflect the sunlight passing into the chamber, and in this way reduce the amount of solar heat passing through the window, and, in the case of an absorbent fluid, to retain the heat for later use. Pleasing architectural aesthetics or practical advantages in the case of greenhouses may further be obtained by passing colored fluid through the chamber which fluid may additionally achieve the selective absorption of light of certain wavelengths passing through the window. An alternative embodiment of the invention includes providing the inside window panel with grooves adjacent the chamber and disposed at such an angle thereto that radiation in a spectral region in which the material of said window is at least partially transparent attempting to pass outwardly through said window is substantially reflected back into said structure. Accordingly the angle at which the walls of such grooves are disposed must exceed the critical angle to support total internal reflection for the particular materials utilized.

Claims

1. A solar window for use with at least a partially enclosed structure and mounted with respect thereto so as to receive light rays thereon, said window comprising a pair of substantially transparent panels disposed in opposed position to each other and defining at least one fluid receiving chamber therebetween, one of said panels including a plurality of generally parallel grooves having sidewalls disposed at an angle such that light attempting to pass through said window in the direction of said one panel towards said other panel is substantially total internally reflected away from said one panel by means of total internal reflection, and wherein said grooves are formed within said one panel, said one panel formed of a material having a substantially higher index of refraction than that of a first fluid in said chamber, including means for introducing a second fluid into said chamber, said second fluid having an index of refraction closer to that of said one panel such that the critical angle of incidence for said one panel material to support total reflection of radiation passing from said one panel towards said other panel cannot take place such that radiation may freely pass through said window in both directions.

2. The solar window of claim 1, said first fluid being air having an index of refraction of substantially 1.0.

3. The solar window of claim 2, said second fluid being water having an index refraction of about 1.33 and said one panel being formed of an acrylic resin having an index refraction of about 1.49, said grooves (being V-shaped with) having an approximately 90 apex angle and the sides each disposed at about 45.

4. The solar window of claim 2, said second fluid being an aqueous solution of sucrose having an index of refraction of about 1.49 and said one panel being formed of an acrylic resin having an index of refraction of about 1.49, said grooves being V-shaped with an approximately 90°

apex angle and the sides disposed at about 45°

.

5. The solar window of claim 1 wherein said chamber is evacuated.

6. The solar window of claim 1, said second fluid having an index of refraction essentially equal to that of said one panel such that light rays leave said window on a path parallel to that at which they enter allowing clear viewing of objects through said window.

7. A solar window for use with at least a partially enclosed structure and mounted with respect thereto so as to receive light rays thereon, said window comprising a pair of substantially transparent panels disposed in opposed position to each other and defining at least one fluid receiving chamber therebetween, one of said panels including a plurality of generally parallel grooves having sidewalls disposed at an angle such that light attempting to pass through said window in the direction of said one panel towards said other panel is substantially total internally reflected away from said one panel by means of total internal reflection, and wherein there are two opposed panels and a third panel disposed intermediate thereto, said third panel of undulating configuration defining peaks and valleys and disposed at an angular relation to said two panels so as to form adjacent channels wherein alternate channels form two separate fluid chambers.

8. The solar window of claim 7, wherein said panels are of thin wall sheet material.

9. The solar window of claim 7, wherein said third panel is disposed at an angular disposition with regard to said other panels of approximately 45°

.

10. The solar window of claim 7, wherein said channels are substantially V-shaped.

11. The method of regulating the temperature of at least a partially enclosed structure having a solar window mounted with respect to said structure so as to receive the sun'"'"'s rays thereon, said window including a pair of generally transparent panels disposed in opposed position to each other and defining a fluid chamber therebetween, comprising sensing the temperature inside said structure and alternatively permitting the sun'"'"'s rays to pass directly through said window where there is a need for heat in said structure proximate said window so that such window functions as a passive solar heat collector and passing a relatively cool optically dense heat absorbent fluid through said chamber wherein said fluid will absorb heat from sunlight passing into said chamber so as to reduce the amount of sunlight and accordingly solar energy passing into said structure and then cycling said fluid from said window to a heat sump when there is no need for heat in said structure proximate said window wherein said window alternatively functions as an active solar heat collector, wherein said fluid is colored so as to selectively permit light of certain wavelengths needed to support plant growth to pass through and so as to absorb light of certain other wavelengths, and wherein said fluid permits entrance of light of those wavelengths in the 4,000 to 5,000 Angstrom and 6,000 and 7,000 Angstrom ranges and generally absorbs light in all other wavelength ranges.

12. The method of regulating the temperature of a generally enclosed structure having a solar window mounted with respect to said structure so as to receive the sun'"'"'s rays thereon, said window including a pair of generally transparent panels disposed in opposed position to each other and defining a fluid chamber therebetween, the panel mounted proximate the inside of said structure including a plurality of generally parallel grooves and formed of a material having a substantially greater index of refraction than that of the fluid within said chamber, the sidewalls of said grooves being disposed at an angle such that light attempting to pass through said window from the inside out is substantially totally internally reflected into said structure but light impinging on said window from the outside may pass through said window including the step of introducing a second fluid having an index refraction substantially higher than that of said first fluid into said chamber such that light may pass freely through said window in both directions.