Modular tubular solar energy collector apparatus

A solar energy collector module comprising a plurality of tubular collector elements having the same outside diameter and each including a circumferentially transparent outer tube having a closed end and an open end, and, interiorly of said outer tube, a hollow elongated absorber tube radially spaced from said outer tube, having a closed end and an open end and including a solar energy absorbing surface disposed between its ends, said absorbing surface comprising a wave length selective coating thereon, means annularly sealing the outer tube and the absorber tube together adjacent the open end of one of the said tubes to provide a closed annular space between the two, said space being evacuated to sub-atmospheric pressure, the absorber tube having an interior chamber,

• an elongated manifold having lateral, outwardly facing apertures for receiving the open ends of said tubular collector elements, each said aperture including means interiorly of the manifold for closing the open end of the absorber tube and providing an enclosed atmosphere within the interior chamber thereof,
• plural U-shaped elongated fluid tight tubes that are non-reflective of thermal radiation and supported in said manifold, each extending through said absorber tube end closure means of the manifold and along a substantial longitudinal portion of said interior chamber of each of the absorber tubes of the collector elements received by the manifold,
• fluid conduit means in the manifold connecting the U-tubes in series,
• a working fluid supply means connected to one of the U-tubes for introducing a working fluid to the series of U-tubes and in heat exchange relationship respectively with the interior chamber of the series of absorber tubes, and
• means connected to the series of U-tubes for receiving circulated, heated fluid therefrom.

In a solar energy collector apparatus, the combination of

• a support surface for said apparatus exposed to sunlight,
• a manifold means adapted to be connected to said support,
• a tubular solar collector comprised of a hollow double walled glass tubular collector member having its walls spaced apart and the space therebetween evacuated to subatmospheric pressure, the inner wall thereof including a wave length selective coating thereon, said collector being open at one axial end and in operating engagement thereat with the manifold and closed at its opposite axial end,
• end support means engaging the tubular collector member adjacent its closed end adapted for firmly supporting said tubular collector member in a spaced relationship above said support surface,
• said manifold means comprising an elongated, hollow, fluid conducting shaped tubing of a thermally conductive and thermally non-reflective material having two elongated portions connected at their one end by a bight portion and which extends interiorly of said collector member substantially the axial length of the latter and the other opposite ends of the two elongated portions depend outwardly from its open axial end, and
• a body of thermally insulating material surrounding the open axial end of said collector member and the outwardly depending other end portions of said two elongated portions of shaped tubing, and a heat exchange media in said shaped tubing adapted for flow throughout the length thereof.

A modular solar energy collector apparatus comprising

• a pair of spaced, parallel beams,
• an elongated manifold means disposed between said beams,
• means connecting the manifold to each of the beams intermediate their ends,
• a plurality of elongated, tubular solar collectors disposed in equally spaced array on opposite sides of said manifold, one end of each of the collectors being inserted into operating engagement with the manifold and supported thereby,
• end support means oppositely disposed in spaced relation on opposite sides of the manifold and engaging the outer ends of the collectors thereat for firmly supporting the collectors, the end support means and manifold positioning the tubular collectors substantially parallel with said beams, said end support means on either side of the manifold comprising an elongated bracket assembly fastened to each of the parallel beams and including an integral lower bracket element,
• spaced, semi-circular, up-turned, contoured collector rests for nesting said collectors spaced along said lower bracket element corresponding with said collector spacing, and
• an elongated, upper bracket element having spaced, semi-circular, down-turned, contoured collector rests corresponding to said up-turned rests and means for detachably connecting said upper element over said lower element for encircling of the collectors by said combined semi-circular rests thereof for firmly supporting the closed ends thereof in operating position.

A solar energy collector apparatus comprising

• plural double-wall glass tube collectors each having a wave length selective coating on the inner wall thereof defining a solar energy absorbing surface disposed between one closed end and the other open end thereof, the outer wall being transparent, the double walls defining a sealed annular space under vacuum,
• an elongated manifold having juxtaposed, split complementary halves of cellular insulating material and having a rigid, dense, non-porous exterior skin layer over said insulating material,
• a continuous serpentine of thermally conductive tubing comprised of a plurality of series inter-connected shaped U-tubes,
• separate longitudinally disposed inlet and outlet header pipes in said manifold,
• means connecting one end of said serpentine of tubing into said inlet header pipe and means connecting the other end of said serpentine of tubing into said outlet header pipe,
• each of said glass tube collectors encircling a shaped U-tube portion of the serpentine tubing, and the balance of said serpentine of tubing depending from the open end of each double-wall glass tube collector and enclosed by said juxtaposed manifold halves,
• the open end of each said collector also being inserted into the manifold and said end opening substantially closed thereby, the opposite closed end depending laterally from said manifold,
• said enclosed U-tube portion in each of the double-wall collectors having a thermally non-reflecting exterior surface,
• the interior of the tube collectors containing a non-turbulent atmosphere of gaseous media surrounding said U-tube portion therein, and
• a liquid supply adapted to be connected to said inlet header pipe for filling said inlet header pipe, said serpentine of tubing and said outlet header pipe.

In an elongated, tubular solar collector apparatus having a double-wall glass tube and a sealed annular space between the walls at subatmospheric pressure, said tube having a closed end and an open end, the inner wall thereof defining a tubular chamber closed at the one end and open at the other end and encircled by the said annular space at subatmospheric pressure, the outer wall being transparent to solar radiation, the improvement therein comprising

• a solar energy absorbing, wave length selective surface coating on the inner wall of said double-wall tube and substantially covering said tubular chamber of the inner wall,
• an elongated, continuous, bent tubing that is non-reflecting in thermal radiation and having an O.D. that is substantially smaller than the diametrical dimension of the said tubular chamber of the double-wall tube and formed to a configuration having two elongated portions connected to each other through a bight portion at one end of said tubing formation and separate from each other at the opposite end thereof for inlet and outlet, respectively, of a fluid adapted for flow therethrough, said formed tubing being disposed inside said chamber of the double-wall tube and extending along a substantial portion of the length of said chamber, and
• a quiescent gaseous heat transfer media in said tubular chamber and surrounding said formed tubing therein, the latter being fluid tight for circulation of fluid media through the tubular chamber of said double-wall tube and extract thermal energy therefrom.