text:
|Publication number
|Publication type
|Application number
|Publication date
|Oct 12, 1976
|Filing date
|Apr 22, 1974
|Priority date
|Apr 22, 1974
|Also published as
|Publication number
|Narinder S. Kapany
|Original Assignee
|Kaptron, Inc.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (13), Referenced by (88), Classifications (30), Legal Events (1)
|External Links: USPTO, USPTO Assignment, Espacenet
The present application is related in part to the applicant's copending application, Ser. No. 462,856, filed Apr. 22, 1974, and entitled HIGH EFFICIENCY LIGHT TRANSMITTING WINDOW PANEL.
The invention relates to a solar panel and more particularly to a high efficiency solar panel for converting incident solar light into heat.
In some prior art types of solar panels, the incident light passes through a window to a heat absorber. The window is intended to transmit solar radiation while trapping the re-emitted infrared radiation from the absorber. The window also reduces convection losses using "hot house" and "window pane" techniques. The window sometimes consists of one or more layers of transparent glass or plastic separated by air. The absorber is designed to be heated by absorption of the energy incident from the sun and to transmit this heat to a heat transfer fluid, which is typically water or air. The absorber is insulated to minimize heat loss to the surroundings. Each of the components and more particularly the window and the absorber can be improved by the application of optical techniques.
The window portion should be higly transmitting to light having a wavelength in the 0.3 to 2 micron range. Also the transmission of the incident light should be independent of the angle of incidence or polarization, thus making the solar panel useful even on a cloudy day while avoiding the use of expensive mechanical tracking systems. Infrared re-radiation from the absorbing portion should be trapped within the panel. The window portion should be made of low cost materials without sacrificing sturdiness.
Some of these requirements are contradictory. For example, in order to make the window portion sturdy or in order to make it more effective in trapping infrared re-radiation, some prior art panels are made with relatively thick window portions which have lower light transmitting qualities than relatively thinner sections. Thus, the light transmitting capability is degraded to improve the capability to trap re-emitted infrared radiation. Furthermore, when the window portion is made relatively thick the acceptance angle properties of the window portin may be degraded in some prior art arrangements.
The ideal absorbing portion must have a high absorptivity for light wavelengths in the 0.3 to 2 micron range and a low emissivity for light wavelengths in approximately the 10 micron range. For a black body, the ratio of absorptivity to emissivity is approximately one whereas for a polished metal surface this ratio is approximately three. Ratios on the order of nine have been obtained by coating a thin absorption layer over a reflecting surface. The layer is thick enough to absorb solar radiation but thin compared to the wavelength of the infrared. In prior art devices of this type, however, such coatings tend to be difficult to apply and lose their high absorptivity to emissivity ratio with age. The disadvantage of a simple polished metal surface is that it is highly reflecting with a reflectivity constant of approximately 0.9. Further, design requirements for such absorbing portions are that they should give good contact with the fluid to be heated, be inexpensive to manufacture and should reduce convection losses.
The above described disadvantages of the prior art are overcome and the requirements for a high efficiency solar panel are met by the present invention of a solar panel for converting incident light into heat comprising a heat absorbing portion and a window portion interposed between the incident light and the heat absorbing portion with at least one of the heat absorbing and window portions having a plurality of opposed reflecting surfaces which transmit the incident light by multiple reflections to the heat absorbing portion. By "opposed reflecting surfaces" is meant that that separate ones of the plurality of reflective surfaces are spaced apart from and face each other, either directly or obliquely, so that multiple reflections can occur.
In some preferred embodiments of the invention, the plurality of opposed reflecting surfaces converge in the overall direction of the light travel from the window portion to the heat absorbing portion. In one such embodiment, for example, the opposed reflecting surfaces are arranged in V-shaped, parallel grooves.
In some preferred embodiments means are also interposed between the reflecting surfaces and the heat absorbing portion to reflect infrared light emitted by the heat absorbing portion back to the heat absorbing portion. For example, as part of the window portion of one such embodiment, a plurality of parallel, triangularly shaped wedges are provided for supporting the opposed reflecting surfaces. Each wedge has one apex pointing away from the heat absorbing portion and supports a pair of reflecting surfaces which diverge from the one apex in the direction toward the heat absorbing portion. Thus, in effect, the reflecting surfaces facing each other which are supported by each pair of adjacent wedges converge in the direction of light travel to the absorbing portion. In this preferred embodiment the means for reflecting the infrared re-radiation comprises infrared reflecting surfaces which are disposed between the other two apexes of each wedge, that is, the infrared reflecting surfaces are arranged so as to face the heat absorbing portion and are supported adjacent to the flat surface of the bottom of each wedge. In other embodiments the opposed reflecting surfaces are on self-supporting substrates arranged in parallel V-groove fashion. Both the V-groove and wedge configurations preferably have their longitudinal axes aligned along the direction of solar travel over the panel, for reasons which will be explained in greater detail hereinafter. The infrared reflecting surfaces also may have a variety of shapes such as flat, inverted V-shaped grooves, or even concave, hemicylindrical grooves.
The window portion in other embodiments of the invention comprises a pair of thin transparent sheets which are separated by a plurality of ribs made of light transmitting material arranged to transmit the incident light striking the window within a predetermied angle of acceptance to the heat absorbing portion by means of multiple total internal reflections. In one embodiment, for example, the ribs take the form of a plurality of transparent columns while in other embodiments the ribs are in the form of transparent zig-zag walls or a honeycomb structure. In these embodiments the window portion preferably further includes means for segmenting air spaces between the sheets to reduce convection losses and to distribute better the mechanical load applied to the window. This form of construction has the advantages of light weight, sturdiness, high light transmission and low cost.
In these and other embodiments, the heat absorbing portion may include a top panel of reflective surfaces arranged in honeycomb fashion to receive the incident light passing through the window portion and to transmit the light to the heat absorbing portion. The honeycomb panel has the reflective surfaces preferably arranged to taper downwardly into the heat absorbing portion so as to absorb the energy of the light during multiple bounces and to trap the air above the heat absorbing portion, thereby reducing convective heat losses.
In still other embodiments the top panel of the absorbing portion is provided with a plurality of parallel grooves which may, for example, have a V-cross-sectional shape. The longitudinal axis of such grooves is preferably oriented along the axis of solar travel over the panel for maximum receptivity and absorption of the incident light.
Many of the above described features of the invention may be utilized independently of some of the others, but they are preferably combined into one embodiment which is highly efficient in converting incident solar radiation into heat.
It is therefore an object of the present invention to provide a panel which is highly absorbing for incident light radiation having a wavelength in the range of 0.3 to 2 microns;
it is another objecct of the invention to provide a heat absorbing panel which has a low emissivity at radiation wavelengths corresponding to the temperature of the absorber when the emitted light wavelength equals 5 to 15 microns;
it is a further object of the invention to provide a high efficiency panel for converting incident light into heat wherein the panel is lightweight and sturdy; and
it is a still further object of the invention to provide a high efficiency heat absorbing panel which has low heat losses due to radiation, convection and conduction.
The foregoing and other objectives, features and advantages of the invention will be more readily understood upon consideration of the following detailed description of certain preferred embodiments of the invention, taken in conjunction with the accompanying drawings.
FIG. 1 is an exploded, perspective view, partly in section and with portions broken away of a solar panel according to a first embodiment of the invention;
FIGS. 2a and 2b are enlarged perspective views, partly in section and with portions broken away of alternative window panels for the embodiment depicted in FIG. 1;
FIGS. 3a and 3b are enlarged perspective view, with portions broken away and in section of the rib portions of the window panels depicted in FIGS. 2a and 2b;
FIG. 4 is an enlarged vertical view, in section, and with portions broken away of a window sheet of the embodiment of FIG. 1;
FIG. 5a is a perspective view of a modified window panel for the embodiment of FIG. 1 with portions broken away;
FIG. 5b is an enlarged vertical view, in section, of the structure depicted in FIG. 5a;
FIG. 5c is an enlarged vertical view, in section, of a modification of the structure depicted in FIG. 5b;
FIG. 5d is a perspective view of a second modified embodiment of the invention, with portions broken away and in section;
FIGS. 6a and 6b are diagrammatic illustrations for use in explaining the operation of the window panels depicted in FIGS. 5a-5d;
FIG. 7 is a perspective view of a third modified window panel for the embodiment of FIG. 1, with portions broken away; and
FIGS. 8 and 9 are perspective views partly in section and with portions broken away of alternative top panels for the absorbing portion.
Referring now more particularly to FIG. 1, the combined solar panel of the invention includes a window panel portion 10 and a heat absorbing portion 12. The heat absorbing portion 12 further includes a fluid heat exchanging chamber 14 and an insulating back 16 for the heat exchanging chamber 14. The heat exchanging fluid, such as water or air, is continuously admitted to the chamber 14 through an inlet pipe 15 and is exhausted from the chamber by an outlet pipe (not shown). In operation, incident solar radiation 18 passes through the window portion 10 to strike the heat absorbing portion 12. The heat generated in the heat absorbing portion 12 by the solar radiation 18 is transferred to fluid passing through the heat exchanging portion 14. This transfer of solar generated heat into the fluid raises its temperature.
As mentioned above, the window portion must be designed to accept solar radiation 18 over as wide an angle of incidence as possible. It also must be designed to prevent heat loss through reradiation from the heat absorbing portion 12 and heat loss due to convection currents above the heat absorbing portion 12.
The window panel 10 includes a pair of thin, transparent sheets 20 and 22 which are spaced apart by a plurality of upstanding columns or ribs 24 which are also made of lightweight, transparent material and preferably of a material which has high optical transmission qualities. In practice, the material chosen for the sheets 20 and 22 and the ribs 24 may be lightweight plastic. In other embodiment, the top sheet 20 may be glass for ruggedness.
Means are provided for segmenting the air space between the sheets 20 and 22 to reduce heat loss due to convection currents which would otherwise develop between the two sheets. In the embodiment depicted in FIG. 1, the means for segmenting the space comprises a plurality of transparent bubbles 26 on the upper surface of the sheet 22. The bubbles 26 may be made of a transparent material such as plastic. The bubbles 26 can be pressed flat against the flat sheets 20 and 22 to reduce reflection losses at the spherical surface.
Referring now more particularly to FIGS. 2a and 2b, other types of columns and air space segmenting are depicted. In the embodiment of FIG. 2a the window sheets 20 and 22 are separated by a plurality of thin sheets 28 turned on edge to form a plurality of parallel ribs which extend the length of the sheets 20 and 22. In the modified embodiment depicted in FIG. 2b, the ribs are a plurality of sheets 30 turned on edge and bent in a zig-zag fashion. In the embodiments of FIGS. 1, 2a and 2b, the ribs 24, 28 and 30 are made of lightweight, optically transparent material. In still other embodiments (FIG. 7), the light transmitting structural support between the sheets may be a honeycomb or other shapes.
The purpose of having the ribs 24, 28 or 30, in addition to separating the sheets 20 and 22 to form an insulating air space, is also to provide means for transmitting incident light striking the top sheet 20 to and through the bottom sheet 22 so that the transmitted light will eventually strike the absorbing portion 12. By providing these ribs, the incident light is accepted over a wider incident angle than if the ribs were opaque and the only light reaching the absorbing portion was light which managed to penetrate both the top and bottom sheets 20 and 22. From Snell's law that n1 sinθ1 = n2 sinθ2 (where θ1 and θ2 are the incident angle and the refracted angle, respectively) and the principle of total internal reflection that the angle (θ3) for light leaving the material having the higher index (n2) of refraction into a material (such as a coating) of a lower refractive index (n3) must be 90� (See FIG. 3b): ##EQU1## Note that θ is measured with respect to the normal of the top surface of the rib, and therefore the actual maximum acceptance angle in the above examples is 2θ1. In the case of wall type ribs, such as ribs 28 and 30, there is some advantage in aligning their longitudinal axis with the direction of travel of the sun over the panel. When this is done the bulk of the incident light will always be within the acceptance angle since the acceptance angle for light contained in all planes which contain the longitudinal axis is substantially 180�.
n1 = refractive index for air or n1 = 1
n2 = refractive index of material of rib 28, and
n3 = refractive index of a protective dielectric coating 29 on rib 28,
where rib 28 is uncoated, n3 = 1 and ##EQU2##
While the above described mathematical relationships between the angle of acceptance and the indices of refraction are given with respect to the rib 28, it should be apparent that substantially similar relationships apply to the ribs 24 and 30. Thus, light is transferred through the area of the window portion which is covered by the ribs by means of multiple, total internal reflections within the ribs 24, 28 or 30.
In some embodiments it is preferable to coat the sheets 20 and 22 with a transparent hard coating 32 in order to prevent scratching and an anti-reflection coating 34 to minimize reflection losses (see FIG. 4). Further, in some embodiments it is preferable to stack a number of window sections 10 to minimize heat losses due to convection and reradiation from the absorbing portion 12.
Referring now more particularly to FIGS. 5a and 5b, still another embodiment of the window section 10 is illustrated. In the embodiment of FIGS. 5a and 5b a panel of optical valves 36 are located beneath the sheets 20 and 22. The optical valves 36 have the effect of admitting incident light to the structure but blocking the escape of a large percentage of the reflected infrared radiation emitted by the absorbing portion 12. The basic structure of each optical valve in the panel 36 is to provide a plurality of opposed reflecting surfaces which converge in the overall direction of light travel from the window portion 10 to the heat absorbing portion 12. The reflecting surfaces of each optical valve of the panel 36 may be in the form of a plurality of reflecting V-grooves or in honeycomb cells but both arrangements have wider openings at the top surface, that is, the surface first struck by the incident solar radiation, than at the bottom surface, that is, the surface closest to the heat absorbing portion 12. The optical valve panel 36 may be composed of combinations of metal and/or dielectric materials.
In the embodiment depicted in FIGS. 5a and 5b, a plurality of downwardly converging V-grooves are formed by constructing the panel 36 of upwardly pointing, triangularly shaped wedges 38 of low refractive index material interspersed between downwardly pointing, truncated triangularly shaped wedges 40 of high refractive index material. The incident solar radiation is transmitted through the high refractive index medium 40 and is reflected at each interface formed between a wedge of high refractive index material 40 and a wedge of low refractive index material 38. Thus, these interfaces formed by the discontinuities in the refractive indices are effectively reflective surfaces 42 for the incident solar radiation. Such a reflecting surface 42 is formed on the opposite, downwardly converging sides of each wedge 40 and thus light entering the top of the wedge 40 is multiply reflected downwardly towards the heat absorbing portion 12 (not shown in FIG. 5b) which is below the optical valve panel 36.
In order to prevent the escape of infrared radiation emitted by the heat absorbing portion, a plurality of infrared reflecting surfaces 44 which face the heat absorbing portion 12 are provided on the bottom of each wedge 38. Therefore this optical valve panel 36 is highly transmitting for incident solar light and highly reflecting for the far infrared which is re-emitted by the heat absorbing portion 12.
Referring now more particularly to FIGS. 5c and 5d, metal or multiple dielectric layers are used for reflection in place of the wedges 38 and 40 of transparent material. In particular, in the embodiment of FIG. 5c a plurality of opposed reflecting surfaces 46 are embedded in a transparent medium 48. The opposed reflecting surfaces 46 are inclined to converge downwardly towards the heat absorbing portion 12. The infrared reflecting surfaces 44 are placed on the bottom of the panel of material 48 between pairs of opposed converging surfaces 46 in a manner similar to the embodiment of FIGS. 5a and 5b.
In the embodiment depicted in FIG. 5d, thin flat laminates 50 are attached together along one edge to form a downwardly opening V-shaped channel 52. A plurality of the V-shaped channels 52 are aligned parallel to each other and extend along the length of the solar panel. The opposed reflecting surfaces of each adjacent pair of reflecting channels 52 form a pair of downwardly converging reflecting surfaces as in the other optical valve embodiments described above with reference to FIGS. 5b and 5c. The bottom of each V-shaped channel 52 is open so that infrared radiation emitted from the heat absorbing portion 12 strikes the interior surfaces of the V-shaped channel 52 which face the heat absorbing portion 12 and is re-reflected back to the heat absorbing portion 12 by multiple reflections within the V-shaped channels 52 as indicated by the dashed line path in FIG. 5d. In other embodiments, the infrared reflecting surfaces may be flat, curved or even corner cubed and are not necessarily merely the backside of the laminates 50.
The reflective surface 46 and 50 may be polished metal or multiple layers of dielectric coatings over the channel surfaces to form a reflective laminate. One advantage of dielectric coatings over metal surfaces is that dielectric coatings can be made with a higher reflection coefficient than the metal surfaces alone but generally for smaller angles and wavelength ranges.
One important consideration in the design of these optical valves 36 is the acceptance angle for solar radiation. If the light striking the top of the panel 36 is at too large an angle with respect to the normal to the top of the panel 36, then the incident light will be returned out the top or refracted out of the panel rather than be passed through it by multiple reflections. In all planes containing the apex line of the V-groove, all incident angles of solar radiation are accepted. Thus, with reference to FIG. 5a, incident light striking the panel 36 in a plane which is normal to the panel 36 and which passes through the lower apex of any given wedge 40 will be accepted.
Referring now more particularly to FIG. 6a, which is an enlarged and perspective view of the embodiment depicted in FIG. 5d, the apex line is defined as a line 54 which is centered between the opposed reflecting surfaces 50 at their closest points and parallel to the top surface of the panel 36. For light striking the top of the panel 36 in a plane which is normal to the apex line 54, it can be shown that the acceptance angle of the incident light is: ##EQU3## and the full acceptance angle, 2θmax (i.e. the light striking from either side of a line normal to the top of the panel 36) is: ##EQU4## where d2 is the width of the smaller end, and d1 is the width of the larger end of the V-shaped groove formed by the opposed reflecting surfaces 50. For any larger angle the incident light will not be multiply reflected toward the apex but instead will be reflected upwardly of the V-groove.
When the groove consists of two different dielectrics, as depicted in FIGS. 6b and 5b, for example, the full acceptance angle can be shown to be: ##EQU5## where n = refractive index of wedge 40, and n' = refractive index of wedge 38. See Fiber Optics, pp. 18-21, by N. S. Kapany, the present applicant, (Academic Press, New York 1967).
While in the above described embodiments, the optical valve panel 36 is illustrated in the figures as comprising a plurality of V-grooves, in other embodiments (FIG. 7), as mentioned above, it has a honeycomb cell structure 60 wherein the opening closest to the incident light is wider than the opening which is closest to the absorbing portion 12. The opposed plane surfaces inside each honeycomb cell of the structure 60 provide a plurality of opposed reflecting surfaces which operate in substantially the same manner as the V-groove arrangement shown above so that a detailed description of the honeycomb arrangement will be omitted.
The honeycomb structure 60 may be situated between the sheets 20 and 22 (as shown in FIG. 7) or it may be a separate panel below the sheet 22. The plane surface area 62 of the structure 60 below and between the honeycome cells is preferably a reflecting surface for the infrared radiation emitted by the absorbing portion 12.
One advantage of this structure over the V-groove or wedge configurations is that it is non-axially directional. The V-groove or wedge structures of FIGS. 5a-5d preferably are utilized with their longitudinal axes aligned with the sun's direction of travel over the panel so that the bulk of the incident light will always strike within the incident angle of acceptance. This is true because for light contained in a plane passing through their longitudinal axes the V-groove or wedge structures have an acceptance angle of nearly 180�. With the honeycomb structure 60, however, the sun's direction of travel is not material since light is accepted in the same manner for any given incident angle within the acceptance angle with respect to the normal to the panel for all radial directions about the panel.
Another advantage of the honeycomb cell structure 60 over some other designs is that it is very effective in segmenting the air space above the absorbing portion to reduce convection heat losses.
Referring again more particularly to FIG. 1, as mentioned above, the ideal absorber has a high absorptivity in the wavelength range of 0.3 to 2 microns and a low emissivity in the wavelength range of approximately 10 microns (the far infrared). In the embodiment depicted in FIG. 1, the absorbing portion 12 has a tapered honeycomb structure 56 embossed directly on the upper face of the top panel 58 of the heat exchanger 14. The embossed honeycomb structure 56 provides multiple bounce absorption of the incident light ray transmitted through the window portion 10. The multiple bounce absorption is substantially similar in operation to that described above with reference to the reflecting surfaces for the optical valve structure 36, that is, the incident light passing through the window 10 is reflected a multiple number of times within the hollows of the honeycomb structure 56 until it strikes the upper surface of the heat exchanger 14 where the incident light is converted into thermal energy.
The honeycomb structure 56 gives good contact between the heat exchanger 14 and the fluid to be heated and it is inexpensive to manufacture in large quantities. In other less advantageous embodiments, the honeycomb structure 56 is not tapered downwardly towards the heat exchanging portion 14 and has a substantially uniform cross section. The advantage of having a multiple bounce absorption structure is that it provides high absorption with low emissivity of infrared. This is because although a polished reflector has a low absorptivity, ρ, for a single bounce of the incident radiation, the fractional absorption for n bounces is (1 - ρ)n.
For example, if ρ equals 0.8 and n = 3, approximately 99% of the incident energy is absorbed by the absorbing portion 12. In this manner a high ratio of absorptivity to emissivity can be obtained while still maintaining appreciable absorption. In addition, the honeycomb structure illustrated in FIG. 1 reduces convection losses because the air above the heat exchanging portion 14 is compartmentalized. Furthermore, the top of the honeycomb structure 56 can be covered with a light transmitting panel which may, for example, be the bottom sheet 22 of the window portion to enhance the compartmentalization of the air above the heat exchanging portion 14.
In other embodiments, the top panel 58 of the absorber may have V-grooves similar to those shown for the optical valves 36, for example. In still another embodiment, referring more particularly to FIG. 8, the top panel 58 has a plurality of upstanding metallic fibers 64. These fibers 64 absorb the heat energy from the incident light and conduct it to the panel 58. They also reduce heat loss due to convection by trapping the air immediately above the panel 58. The fibers 64 are preferably coated to more effectively absorb the heat energy of the light while reducing the infrared emission.
The panel embodiments have been described above as generally flat but in other embodiments they may be curved to give a concentrated effect. In such embodiments, either or both the window and heat absorbing portions 10 and 12, respectively, may be curved. Thus, for example, referring more particularly to FIG. 9, the honeycomb dimpled top panel 66 of the heat absorber 14 may have a curved cross section.
Although the insulation backing for the heat exchanger 14 is shown as being fiberglass in FIG. 1, in other embodiments the insulation may be composed of a multilayer structure of alternating sheets of reflective and dielectric material. In still other embodiments the insulating portions may be segmented plastic sheets of the type described above in reference to the window portion 10 with a reflecting surface below.
While the panel of the invention has been described above for use in converting solar radiation into heat, it should be apparent that it may also be used for converting incident radiation from other sources, both natural and man made, into heat.
The terms and expressions which have been employed here are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described, or portions thereof, it being recognized that various modifications are possible within the scope of the invention claimed.
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|Aug 24, 2004
|Mar 2, 2006
|General Electric Company
|Photovoltaic integrated building component
|Oct 12, 2006
|Oct 4, 2007
|David Bayne
|Greenhouse insulation system
|Dec 5, 2006
|Jun 5, 2008
|Nix Martin E
|Use of renewable energy like solar, wind, geothermal, biomass, and hydropower for manufacturing combustion air for a fossil fuel burner and firebox
|Apr 19, 2007
|Jun 12, 2008
|Sunmodular, Inc.
|Modular solar panels with heat exchange & methods of making thereof
|Apr 20, 2007
|Jun 12, 2008
|Sunmodular, Inc.
|Photovoltaic cells, modules and methods of making same
|May 18, 2007
|Jun 12, 2008
|Sunmodular, Inc.
|Interlocking solar roof tiles with heat exchange
|May 18, 2007
|Jun 12, 2008
|Sunmodular, Inc.
|Solar roof tiles with heat exchange and methods of making thereof
|May 18, 2007
|Jun 12, 2008
|Sunmodular, Inc.
|Photovoltaic roof tiles and methods of making same
|Jan 22, 2007
|Jul 24, 2008
|Wal-Mart Stores, Inc.
|Solar heating system and architectural structure with a solar heating system
|Jun 2, 2006
|Dec 18, 2008
|Barry Clive
|Solar Concentrator
|Sep 9, 2009
|Mar 11, 2010
|David Bayne
|Greenhouse insulation system
|Dec 15, 2009
|Jun 17, 2010
|Pvt Solar, Inc.
|Method and structure for hybrid thermal solar module
|Aug 14, 2009
|Aug 18, 2011
|Derek Montgomery
|Solar collector panel
|Mar 19, 2010
|Sep 22, 2011
|John Randall Schwarz
|Method and Apparatus for Collecting Solar Energy
|May 27, 2010
|Dec 1, 2011
|Paul August Jaster
|Thermally insulating fenestration devices and methods
|Mar 14, 2014
|Sep 18, 2014
|George E. Taylor
|Solar heating system
|Apr 23, 2015
|Aug 13, 2015
|Mark W. Miles
|Solar flux conversion module
|Apr 23, 2015
|Aug 13, 2015
|Mark W Miles
|Solar flux conversion module
|Feb 2, 2000
|Sep 3, 2008
|Multiflecting light directing film
|May 30, 1978
|Feb 15, 1979
|Union Carbide Corp
|Sonnenheizgeraet fuer luft
|Sep 11, 1978
|Mar 22, 1979
|J Kravitz
|Solar panel unit
|Jun 4, 1997
|Dec 11, 1997
|Pertti Anterow
|Solar collector
|Nov 6, 1998
|Feb 3, 2000
|Moseshvili Aleksandre S
|Solar radiant energy concentrator
|Jul 7, 1999
|Feb 3, 2000
|Moseshvili Aleksandre S
|Radiant energy concentrator
|Feb 2, 2000
|Aug 9, 2001
|Trivium Technologies, Inc.
|Multiflecting light directing film
|Nov 1, 2004
|May 11, 2006
|Zhores Ivanovich Alferov
|Photovoltaic module
|Apr 20, 2015
|Oct 29, 2015
|Babcock & Wilcox Power Generation Group, Inc.
|Method to construct and support tube module assemblies for solid particle solar receiver
|U.S. Classification
|126/687, 52/306, 428/179, 136/248, 52/789.1, 126/643, 126/907, 359/596
|International Classification
|Cooperative Classification
|European Classification
|Apr 18, 1986
Owner name: KAPANY CORPORATION, 3460 WEST BAYSHORE ROAD, PALO
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KAPTRON, INC., A CORP OF CA.;REEL/FRAME:004535/0859
Effective date: 19860228


text:
I've been sleeping earlier and earlier the past few days. I went to bed at midnight yesterday, before 1am the day before, and before 2am the day before that. And there were times in the weeks that preceded that I was sleeping at maybe 3am. The result would be that I would wake up tired and groggy– this would never seem too terrible at the moment of waking. It would seem like the same as any other day. But after I get to work, I would be tired and groggy.
The worst part is, it's never completely clear that this is actually the case. I think I took a 20 minute nap at work yesterday and I felt a little bit refreshed, but really, it's no substitute for good, deep sleep. Which makes me want to take a little time to explore my experience and history with sleep, just as a while ago I found myself thinking about my history with food.
I read a quote recently– I'm not sure if it was on Reddit or Hacker News or somewhere– maybe Tumblr, maybe an Imgur picture quoting Tumblr (that's probably it– it's all the same, it's all a blur now, the nature of modernity is that everything from everywhere is happening all at once)– about someone talking about their experience staying up late. Between 1am and 4am, he or she said, the world is quiet and still, and you can ignore your obligations, your responsibilities, the consequences of your actions. It's the romance of late nights, the time out of time, where you are completely free to do as you please. In Singapore, if you like, you can even go out and have supper.
When I look back on my life, there have been times where time spent with friends between 1am and 4am was some of my favorite times. I used to play video games at friends houses, or smoke at void decks and drink beer and talk about what life had in store for us ahead, or talk about relationship problems, and wonder if we'd ever figure it all out– or if we'd get any better at this whole living thing. I think for younger folks– teenagers, especially, the night has a certain sense of freedom calling. Your parents are asleep, your teachers are asleep, the witching hours are the time where you can be free. These are probably the times where teenage boys and girls sneak out of their homes to go and make out in the playgrounds– spaces which enable children's play in the daylight would afford semi-privacy for quivering, wandering hands, fingers, lips.
For me, the late nights were the quiet times, the downtime away from all the pesky people who fill up my day like swarms of insects, buzzing and yapping and moving around in their clunky, obtuse ways. I have to admit, these are my feelings as I write this– people often annoy and frustrate me. I like persons– George Carlin said that when you catch an individual in person, you can see the Universe in his eyes if you're really looking. But groups of people, swathes of people, they can be sickening and overwhelming.
I don't mean that personally. Every person must feel the same way about my role in the crowd, too. We are all traffic. We are all the plague on our own houses. And every day I feel worn down and abused by the throngs of people on the trains. Some people are fine, but there are always those who are loud and obnoxious and abrasive, and a part of me always wants to lash out at them, speak up and put them in their place somehow.
But I know that that would itself be unnecessary provocation, that my expression of annoyance would further annoy and frustrate others, and so I just allow it to boil inside me, hopefully distracting myself with things on my phone, maybe listen to some music, maybe try to be a little bit meditative. Nothing quite works, and the commutes just wear you down. Perhaps someday I will be able to afford taking a cab, perhaps driverless cars will soon be a thing (I wish for this so hard), or perhaps I will move somewhere that isn't as inaccessible as where I am right now.
But I have to remember to be thankful and grateful and all that, yadda yadda. Suspending that for now to think harder about late nights. I remember the house that my family lived in was always tense. My parents worked out of a home office, and so they were always concerned about work. There was no clear demarcation between work and home in my house, and I didn't want to be a part of it very much.
So I'd typically head out– either stay late in school, or go to friends' homes, or hang out in the library, I don't know. It seems a little neat and tidy to say that I was avoiding home. Was I really? I know that I was never in a rush to go home. There were always some people who would linger– sometimes different people every time, and a few who would linger throughout. And I would stick around to see who would stick around, and to see what would unfold, what fuckery we'd get up to.
I'd notice the same thing happening on Facebook years later, when Facebook came around. You'd see all those green lights in the sidebar, people who're online. And as the night goes on, you'd see more and more of the lights go off, and you'd feel a certain affinity to the last few people who remained. Sometimes people from the other side of the Earth.
I remember chatting from time to time with a friend of my wife's, who was studying in New York. We'd typically chat around 3am or so. I enjoyed our conversations– there was something about tired late nights, something about the darkness, something about the quiet that would bring out something introspective and honest about me. I wouldn't be surprised if– when I someday become a novelist or writer of some sort– I actively sometimes choose to stay up late at night to write.
But lately I've been contemplating the inverse, which I've never fully explored. Sleeping early so that I can wake up late, arising BEFORE the world, allowing the world to come to me. It seems like a much more confident, strong proposition. We'll see how that plays out. It's 1040pm now, and I'm going to bed. It's rather uncharacteristic of me.

subset: commoncrawl


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im 6 months along now and around 4 and a half months i got this really sharp cramping like pain in my lower abdoman and the dr said it was probably just adhesions. well it happened again the other night in the middle of the night i was sleeping and it happened. anyone else experience this? is my dr too indifferent??Answer Question
Asked by disheveled at 4:43 PM on Apr. 15, 2009 in PregnancyLevel 3 (17 Credits)
Answer by Mrs.Owen86 at 4:44 PM on Apr. 15, 2009
Answer by disheveled at 4:52 PM on Apr. 15, 2009
Answer by Mz.PhatPhat at 5:01 PM on Apr. 15, 2009
Answer by newmom092009 at 10:08 PM on Apr. 15, 2009
Answer by disheveled at 3:24 PM on Apr. 16, 2009
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28 Apr
Cardiff Blues finished their home season with a victory over Italian outfit Zebre in the Guinness PRO12.
Mike Brown
Email: mailto:firstname.lastname@example.com Contact: 07886396973
Ben Daniels Participation Officer Rhondda and Merthyr, my role is to run the Primary schools programme for Rhondda and Merthyr where they receive coaching throughout the School year. They also compete in rugby festivals pre and post Christmas. Touch rugby within the secondary schools for girls. After numerous sessions each school has an opportunity to play in the Blues North Touch Festival at the University of Glamorgan. Run Little Stars Programmes for 3-5 and 5-7 year old throughout different venues across my area. Run Rugby Stars Camps throughout the School Holidays all over the Blues Region.


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Now, however, Inn Business has to prove it can actually make some decent money out of its new estate by jazzing up its outlets. The game plan is to create "The Local's Local" pub. In other words, it is not going the whole hog by rebuilding the pubs, changing their character and names in the process. Instead it is sprucing up the tattiest part of its estate - adding a lick of paint or building new loos - and providing a more extensive pub grub menu.
It is also seeking to gradually build up its managed estate and roll out Hooden Horse, the eight-strong branded chain it bought earlier this year, across the South-east. As part of this shake-up, at least 50 or so less well-favoured pubs inherited from its buying spree will be sold off, including the 17-strong Welsh estate.
So far the plan is working. Ignoring acquisitions, operating profits for the six months to May jumped to pounds 2.68m (pounds 1.54m), leaping from pounds 386,000 to pounds 2.92m at the pre-tax level. House brokers Peel Hunt are forecasting current year pre-tax profits of pounds 6.45m, putting the shares, which edged up 1.5p to 66.5p yesterday, on a prospective p/e ratio of under 10.
On the face of it, that looks an unjustifiably wide discount to the sector which is trading on a prospective p/e ratio of more than 15. But Inn Business cannot afford to make another acquisition without issuing paper. Until it can prove it can make a good and sustainable return from its investment programme, the shares are no more than a hold.Reuse content


text: '╗┐ Josh Fields (infielder) : Ask Biography RSS Josh Fields (infielder) MLB Player informationNameJosh FieldsPositionThird baseman / Left FielderBatsRightThrowsRightMLB debutSeptember 13, 2006 for the Chicago White SoxCareer statisticsBatting average.234Home runs34Runs batted in107Teams *Chicago White Sox (2006 ¢ 2009) *Kansas City Royals (2010) *Yomiuri Giants (2011 ¢ present) (NPB) Home | Baseball | Josh Fields (infielder) Joshua Dean Fields (born December 14, 1982, in Ada, Oklahoma) is an American professional baseball infielder for the Yomiuri Giants of Nippon Professional Baseball. He was selected as the 18th overall pick in the first round of the 2004 Major League Baseball Draft by the Chicago White Sox. He has also played for the Kansas City Royals. Warning: simplexml_load_file(http://gdata.youtube.com/feeds/api/videos/-/Josh/Fields/(infielder)?orderby=viewCount&max-results=10) [function.simplexml-load-file]: failed to open stream: HTTP request failed! HTTP/1.0 410 Gone in /home/askbio/public_html/index_bio.php on line 257 Warning: simplexml_load_file() [function.simplexml-load-file]: I/O warning : failed to load external entity "http://gdata.youtube.com/feeds/api/videos/-/Josh/Fields/(infielder)?orderby=viewCount&max-results=10" in /home/askbio/public_html/index_bio.php on line 257 Fatal error: Call to a member function children() on a non-object in /home/askbio/public_html/index_bio.php on line 260


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Can You Beat the Time of These Celebrity Triathletes?
Triathlons are no joke. It involves a rigorous course of swimming, cycling, and running all in one race -- a true test of endurance and strength!
What to know more about Obstacle Races?
Want to know more about Obstacle Races in the Philippines? Catch one of the upcoming events hosted by the Philippine Obstacle Sports Federation (POSF) together with Team Reebok Philippines!
Under Armour 3×3 Southeast Asia 2017 Tournament
High performance sportswear label Under Armour announces registration sponsorship for the U18 participants of the Under Armour 3x3 Southeast Asia 2017 Tournament in Philippines.
Kuya Kim Atienza Conquers The Boston Marathon
Kuya Kim Atienza finished strong with the time of 3 hours, 57 minutes and 55 seconds (3:57:55) in Eastern Massachusetts, Boston.
Run Happy Crew at Kerry Sports Manila
Run Happy Crew is a collaboration between Brooks, 2XU and Pace Prehab & Recovery. It is the first co-branded weekly running clinic that focuses on specific running topics weekly.
5 Best Natural Sources of Protein
Protein is essential for muscle growth and can prevent weight gain as it gives a sense of fullness because it breaks down slower than 'quick carbs', which digest instantly. In the recent years health shops have also sprouted like mushrooms supplying easy-to-prepare supplements like Protein Bars and Whey Protein powder.
Run United Exceed 21K 2017 Race Results
Congratulations to all the participants and finishers of the recently concluded Run United Exceed 21K held in Bonifacio Global City! How was your race on the Skyway? Here are the race results and some photos.
Raje Fama and Joyce Reboton won the Under Armour Test Of...
The Philippine leg of Under Armour's 'Test of Will', took place last weekend at Glorietta Activity Center in Makati City.
Kerry Sports Vertical Run 2017 in Shangri-La Fort
One of Manila's tallest buildings, Shangri-La at the Fort, will once again host the city's only international stair climbing race – the Kerry Sports Manila Vertical Run!
Ralph Du: From Fat to Effin' Fit
"Kapag gusto mo ang isang bagay, laging may paraan," Ralph says. "Sabi nga ni Papa, ang tao nga nakalakad sa buwan – so walang imposible."
Behind the Scenes with Claire Adorna
The Olympics is a cut-throat competition for only the elite triathletes on the planet. Every athlete dreams of representing their country in the Olympics.
6 Commandments of Running with a Buddy
Running with a buddy can be so much fun! Enjoy the experience to the fullest by keeping these basic rules in mind.
7 Tips on how you can Find more Time to Run
7 Tips on how you can Find more Time to Run If you make health and fitness a priority, you will find a way to...
7 Bad Habits Runners have to Break
Magbago na tayo, bes. Be a smarter, healthier runner this year (and beyond!) by breaking these habits that hinder you from being the best you can be.
9 Runner-Approved Places to Run within Metro Manila
Are you a newbie looking for a place to run, are you a veteran just bored of your usual route?
42k Do's and Don'ts – before Running a Marathon
Here's a thread that has been getting some attention in the Community Forums so I decided to highlight it with it's on post here in the main site! A good read if you are currently training to run for your very first marathon or already a seasoned marathoner. Check it out!


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From this page you can purchase our standard sized Superweb swimming pool winter debris covers. If your cover is not one of our standard sizes then you can calculate the cost on our Cover Cost Calculator and see details of how to order.
The Superweb (sometimes called a criss cross) Cover is the top of the range winter debris cover.
The Superweb is made from high quality, woven,UV stabilised polyethylene fabric. The webbing of the straps is one continuous piece that is sewn to the body of the cover and continues across to form the fixing on the opposite side. Thus the straps criss-cross the cover like a web.
The cover comes with a 5 year warranty.


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11-05-2014 #1
Illuminati Xposed In Pakistan (The Biggest Secrets Of All Time) 2014
Vimeo Link (Must Watch High Quality Link):-
Dailymotion Link:-
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A peek behind the pop:
the science and nutrition
of popcorn
We didn't believe her at first but food scientist Dr Rachel Edwards-Stuart has convinced us that popcorn isn't magic, but science. Really, really delicious science.
So, don your lab coat and goggles and join us as we take a look at the science behind the pop. Plus, we'll answer the age-old question: can something so delicious really be good for me?
The king of corn
There are many different types of corn – flint corn, dent corn, flour corn, sweetcorn, the list goes on and on. But only one very special kind pops to form the delicious fluffy snack we all love so much: the variety known as popcorn.
What makes popcorn pop?
Like most grains, popcorn contains a certain amount of naturally occurring water. As the popcorn kernel is heated, this water boils and becomes steam, causing the inside of the kernel to expand. Once the internal pressure reaches as much as seven times the outside pressure, the outer layer can no longer withstand the build up and gives way. The kernel breaks open… and pops!
Because of the sudden drop in outside pressure, the inside immediately expands to fill the space, puffing up into delicious, fluffy white popcorn.
There are two main types of popcorn kernel: butterfly and mushroom. Butterfly popcorn is so called because of its irregular shape and many jutting "wings". Mushroom popcorn is rounder, larger and has a more uniform shape. Because of this, it needs a higher temperature and will usually take longer to pop.
We love both but because of its slightly larger surface area, mushroom popcorn is often favoured for sticky toppings like caramel or chocolate.
Speedier when wet
If you soak popcorn kernels in water just before you heat them, more steam will be produced and they'll pop faster and more efficiently.
Enough science, is it good for me?
Air-popped popcorn is naturally high in fibre and antioxidants, low in calories and fat and completely free from sugar and sodium. So, in short, yes – homemade popcorn can be a great choice if you're trying to cut down on sugary snacks, counting calories or want to help lower your cholesterol by boosting your fibre intake.
Of course, you can also go wild and make your popcorn as decadent as you like with an indulgent topping!