Abstract:
The invention consists of an improved heat exchange conduit formed between pre-fabricated building panels and a daylighting section integral within pre-fabricated, structural panels. The daylighting section has the capability to take ceiling air (or air below free-standing arrays) and either return it to the building during heating months, reject the heat, or shunt it for other uses after being warmed through a dual pane glazing assembly with infrared rejection. During summer days, this allows for dramatic reduction in building cooling demand. 
     Heat exchange surfaces within the conduit are thermally tied to the exterior components of the panels to allow heating by solar insolation or cooling to night sky or air. An advanced insulation system adds to thermal performance and sealed insulation cavities prevent moisture degradation of R-Values. Passage through the heat exchange conduit allows for active whole roof solar collection in spring/fall and night cooling capability during summer night operation.

Description:
[0001]    The following is a utility application by Paul H. Hartman for a system to improve heating and cooling performance in buildings converting provisional Pat. No. 61/796,523 filed on Nov. 13, 2012 under the title ‘Daylighting and Night Cooling System’. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to specifically to arrays of pre-fabricated structural panels to improve the efficacy of daylighting, heating, ventilation and air conditioning systems used in building operations. 
         [0004]    2. Description of the Prior Art 
         [0005]    Key metal building roofing improvements of in the areas of reducing moisture vapor permeation of through the roof deck, (to limit corrosion and maintain insulation values) and improving roof insulation, are not addressed in many current metal building roof decks. One area of the prior art in double roof plenum air source solar collectors such as Pulver (U.S. Pat. No. 3,994,276) and Johnson (U.S. Pat. No. 4,054,246) exacerbates these problems. While the roof deck amounts to about 23% of heating load in commercial buildings, the net effect is very small on the cooling load in commercial buildings (Huang 1999 and  FIGS. 10   a ,  10   b ). Because of poor insulation in commercial roofing, typically R-9.9, the net effect of the roof deck on cooling load is negligible compared to other loads such as equipment (Lee 2013), lighting, and vertical glazing. 
         [0006]    Cooling as a major peak summer load factor, along with daytime lighting can be seen as the major cause of grid failures/brownouts and is very important to a number of cooling intensive applications e.g. computer server centers, retail stores, offices, hospitals and supermarkets. 
         [0007]    While Hartman (U.S. Pat. No. 6,959,520) effectively addresses the issues of improved insulation and vapor transmission/corrosion; the daylighting section there uses air flow between an upper and lower glazing for the primary purpose of removing heat buildup from that section i.e. not melting the thermoplastic upper glazing. Venetian blind louvers are used between the two glazing lites to modulate entry of both visible and infrared (IR) components of natural light entry into the building envelope. Either or both of these strategies/equipment approaches are used in the prior art of Murray (U.S. Pat. No. 4,730,552), Howe (U.S. Pat. No. 4,577,619), Cummings (RE 33,720) Dittmer (U.S. Pat. No. 5,062,247), Ayles (U.S. Pat. No. 5,435,780), Kastner (U.S. Pat. No. 8,068,282) and surprisingly the 2008 state of the art NY Times facility, (Lee, 2013). Miller (U.S. Pat. No. 4,468,899) and Christopher (U.S. Pat. No. 5,617,682) do not provide for movement of air between two parallel glazing components. 
         [0008]    While the Times facility is not a systems or low-slope flat roof building, some important figures highlight the interactions between artificial/natural lighting, the advanced under floor air HVAC supply method and the cooling load. In a bar chart comparison to an ASHRAE 90.1-2001 compliant system, the new system showed very little reduction in cooling load, although the electrical lighting load was reduced to 56% of the control case. Daylighting influx of heat is the logical source of this equal cooling load as equipment demands are the same and waste heat from the artificial lighting has dropped. 
         [0009]    Artificial and natural lighting make up between 87% and 97% of the total cooling load loads in commercial buildings with other factors such as the floor, building envelope, air infiltration, equipment and occupants being of a lower magnitude and acting to cancel each other out,  FIGS. 10   a / 10   b . In direct sunlight, only about 45% of the energy is in the visible part of the spectrum, while diffuse light (cloudier conditions, North light and winter) contains about 75% of the energy in the visible spectrum, (Duffle, 1991). The balance between shorter days during the heating season and increased visible content comes into play and moves daylighting performance toward a more equal footing (with the same roof daylighting aperture) between the seasons when IR filtering is used. Improved daylighting, heating and cooling systems for commercial structures should take these factors into account, ideally as integrated building envelope solutions. 
         [0010]    In general, the double dome skylights commonly used to illuminate the interior of flat roof buildings do not filter the infrared component of exterior light. They therefore do not afford a significant improvement in air conditioning loading over artificial lighting. Double wall acrylic or polycarbonate plastic prior art leading to the present offerings includes examples such as York (U.S. Pat. No. 6,695,692). For this reason, daylighting codes, (where they are present), limit the percentage of daylighting aperture to 5% of the roof to prevent excessive cooling demand additions, [e.g. California Title 24]. California code recognizes the importance of daylighting in big box stores by requiring daylighting in any ‘room’ over 25,000 SF. It does not take into account IR filtering at present. 
         [0011]    Several skylight systems using a roof mounted dome communicating through a reflective tube to a ceiling fixture, (primarily used in residential or low rise wooden construction) do have IR rejection built into the system. Representative prior art in this area is Jaster (U.S. Pat. No. 7,954,281). Parallel flat plate glazing of this type is represented by Dittmer (U.S. Pat. No. 5,062,247). Both these devices simply vent heated air flow to the exterior, rather than managing the use of the heat inside when it might be needed, again primarily using air flow to prevent melting of outer glazing. Jain (U.S. Pat. No. 6,014,845) uses an unusual diffract grating solution with only one (outer) glazing. 
         [0012]    Other prior art that does not deal with infrared rejection but uses parallel room ventilation with separate glazing units is seen in York (U.S. Pat. No. 6,695,692) and Han (U.S. Pat. No. 6,142,645). In the mix of many very similar elements of prior art in the area of skylights and ventilating devices what is missing is a system focused on day to day and season to season heating and particularly cooling needs. 
         [0013]    Daylighting curbs in the prior art are not often utilized for sloped roof building applications because of a difficult transition and sealing task between commonly used standing seam roof surfaces and the curbs. They are rarely used in retrofit applications for flat roofs as the sealing of the field cut hole for the device is another area of concern. Positive sealing of the glazing against the roof deck is therefore an important property for any improved daylighting/HVAC system. 
         [0014]    Bringing some of the features of an improved system to bear on utilizing night sky cooling techniques, (Martin, 1984), the system could be utilized in a wide variety of buildings with high cooling needs, such as supermarkets and computer server facilities. This would also expand on the very early prior art of solar pioneer Harold Hay in this area. 
       OBJECTS AND ADVANTAGES OF THE INVENTION 
       [0015]    Accordingly, several objects and advantages of the invention are:
   a. An air source solar thermal/night sky cooling system for a roof deck that reduces the deleterious effects of moisture vapor permeation in use while improving roof insulation.   b. A daylighting system with infrared filtering that allows rejection of heat when desired and re-capture of heat for later and alternative uses when desired.   c. A system that integrates the use of night sky cooling and other off peak cooling capability with existing HVAC equipment, while not significantly adding to building cost.
 
Further objects and advantages of the invention will become apparent through consideration of the specifications and drawings:
   
 
       SUMMARY OF THE INVENTION 
       [0019]    The invention consists of an improved heat exchanging conduit formed between pre-fabricated building panels that is fed by a novel daylighting section integral with the panels. The daylighting section has the capability to take ceiling air (or air below free-standing arrays) and either return it to the building during heating months or shunt it for other uses after being warmed through a dual pane glazing assembly with infrared rejection. 
         [0020]    Heat exchange surfaces at the interior of the conduit that are thermally tied to the exterior components of the panels allow transfer to or from the air flows passing through the conduit. This allows for whole roof solar collection in the spring/fall and night cooling capability during summer night operation. Both these operations return conditioned air to the building rather than depending on expensive thermal storage. Optionally, particularly in the case of free-standing arrays for cooling, storage can be used to augment the performance of a nearby HVAC system. Further aspects of the invention can be seen from the specifications. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is an isometric drawing of a panel array for roofing or other structural uses. 
           [0022]      FIG. 2  is a cut away, detail drawing of a panel illustrating features of a thermal plane 
           [0023]      FIG. 3  is a detail section through a cross brace viewed from within the panel of  FIG. 2 . 
           [0024]      FIG. 4   a  is an initial assembly drawing for an inter-panel joint assembly. 
           [0025]      FIG. 4   b  is a cross section of the thermal conduit formed between panels  32  and  33  of  FIG. 1 . 
           [0026]      FIGS. 5   a  and  5   b  are field assembly illustrations of the upper part of the thermal conduit. 
           [0027]      FIGS. 5   c  and  5   d  are assembly illustrations of structural connections to systems and flat roof buildings. 
           [0028]      FIG. 6   a  is an isometric assembly drawing of a daylighting section including components and settings. 
           [0029]      FIG. 6   b  is an operational listing of typical seasonal and daily settings accompanying  FIG. 6   a.    
           [0030]      FIG. 6   c  is an isometric drawing of the basic structure of the same daylighting section 
           [0031]      FIG. 7  is a process flow drawing of the overall daylighting and night cooling system 
           [0032]      FIG. 8   a  is a top view of a daylighting section as indicated in  FIG. 1 . 
           [0033]      FIG. 8   b  is an assembly drawing of the connection between outside glazing and a bulkhead 
           [0034]      FIG. 8   c  is an edge view of the outside glazing 
           [0035]      FIG. 9  is an isometric of an alternate interior glazing including a lower carrier frame for glazing 
           [0036]      FIGS. 10   a  and  10   b  are comparative performance charts of the prior art based on LBL Pub&#39;n 37208 
       
    
    
     DETAILED DESCRIPTION 
       [0037]    1.  FIGS. 1 through 7  show the structure and function of a thermal plane  24  at the exterior of a panel array  21  that can transmit heat to and from a conduit assembly  30  for the purpose of reducing the heating and cooling demands of a building. 
         [0038]    2.  FIGS. 6   a  through  9   b  show the structure and function of an integral daylighting section  68  in: 1) Cutting the infrared (IR) heat content of solar insolation  22  before it enters a building, 2) Removing heat arising from artificial lighting and equipment within the building during peak electrical and air conditioning periods, 3) Drastically reducing the artificial lighting demand of a building during peak summer usage periods, 4) Utilizing the night cooling capabilities of thermal plane  24  to provide off-peak cooling of a building, and 5) Providing for enhanced fire and violent storm resistance. 
         [0039]    3.  FIG. 1  shows a panel array  21  utilizing the invention where specific panels  32  and  33  are tied structurally to frame components ( FIGS. 5   c  and  5   d ) and one another ( FIGS. 4   b  through  5   b ) to form conduit assembly  30 . Solar insolation is illustrated by arrow  22 . Night cooling losses from the array  21  through convective and radiative heat transfer are illustrated by arrow  23 . Panel surfaces preferably comprise a highly emissive coating  118 , commonly made using PVDF polymer, which facilitates night sky cooling by radiation to the night sky. 
         [0040]    4. Conduit assemblies  30  are formed between individual panels such as  32  and  33  ( FIG. 4   b ) and transmit air flows  47  arising from daylighting sections  68  to plenums  78 . In turn, one or more louvers  94  can vent flows outside  79  the building envelope  91  or return thermally modified air flows  80  to inside the building envelope. (See  FIG. 7 ) Air flows into the daylighting sections, arrow  65 , are supplied from below panel array  21 . Inter-panel joints have a weatherstrip seal  38  affixed between them which is shown in  FIGS. 1 ,  4   a ,  4   b  and  5   a  to  5   d.    
         [0041]    5. The panel array  21  can comprise the roof of a systems (sloped roof) metal building as shown in  FIG. 5   c . It can be attached to truss beams  119  of a flat roof metal building (with a slight pitch for drainage) as shown in  FIG. 5   d . It can also be utilized with residential, small office or pole barn wooden construction (not shown) or used as a free-standing energy structure (as indicated in  FIG. 7 ) in parking lots or atop existing flat roofing. 
         [0042]    6. The area indicated by dashed lines  2  in  FIG. 1  is expanded in  FIG. 2  to illustrate the operating components and principles of the invention within panel  32  and the formation of thermal plane  24 . Cross braces  49  tie an up-slope flange  34  and a down-slope flange  35  together both mechanically and thermally, as they are preferably made from aluminum extrusions. Exterior skin layer  36 / 37  is bonded to the flanges at the dotted areas and completes thermal plane  24 . 
         [0043]    7. The strong mechanical tie provided by the cross braces also improves resistance to racking distortion in the panels. As shown in  FIGS. 3 and 4   b , cam levers  74  are secured by screws  74   a  within the slots  74   b  at the lower surfaces of the cross braces. As shown in  FIG. 4   b  the action of levers  74  against flange angles  34   b  during assembly of the panel frame, (not numbered) acts to urge the shaped end of braces  49  against the interior surfaces of flange  34 , improving heat transfer represented by arrow  31   c.    
         [0044]    8. Composite web portions  40 / 41  and insulation layer  48  thermally isolate exterior skin  36 / 37  and thermally conducting flanges  34 / 35  from the lower flanges (not numbered) and interior skin layer  66  (see  FIG. 6   c ). Insulation values exceeding R-40 were achieved in bench testing of a 4 inch thick panel made with compressed conventional fiberglass having special processing used as layer  48 . The present commercial building stock in the country has only R-10 roof insulation. Ashrae 90.1 requires R-30 for systems buildings in most areas of the country. 
         [0045]    9. Web portions  40  and  41  are preferentially made from phenolic resin/fiberglass fabric composites having UL (fire) and NEMA (electrical) ratings. As all of the components in the panels are fire resistant, panels  32  and  33  are intrinsically fire resistant. Considering also the insulating properties discussed above, use in fire prone areas such as parts of the western U.S. could be helpful in reducing damage to property and life loss. 
         [0046]    10. The combination of composite webs, (0.125″ thick), and aluminum flanges results in strong structural characteristics for the panels. In deflection testing similar to ASTM E72, it was found that 4″ thick by 20″ wide panels had a projected deflection of only 1/240 L/d for a uniform load of 35 pounds/SF over a span of 14.5 feet. This is a typical load requirement for most areas of the U.S. 
         [0047]    11. The spacing between cross braces  49   a  relative to the thickness of exterior skin  36 / 37  and the width of the panel  32   a  is chosen to optimize heat transfer  31   a  through skin  36 / 37  while attempting to minimize the material costs of the panel. An initial estimate of a usable ratio between dimensions  49   a  and  32   a  is 1 to 1.5. The central area  37   a  between these structural/major heat transfer components transmits heat through exterior skin  36 / 37  as indicated by dash dot arrows  31   a.    
         [0048]    12. Skin area  36  directly transfers heat to or from flange  34  through a significant overlap area (dotted line on the up-slope side) and skin area  37  directly transfers heat to or from flange  35  through a significant overlap area there. (See  34   a  and  35   a  in  FIG. 4   b ) Heat readily transferred from area  37   a  to cross braces  49 , is transferred through the larger cross section of the braces, (See  FIGS. 3 and 4   b )) to the flanges as indicated by dash dot arrows  31   c.    
         [0049]    13.  FIG. 4   b  is a cross section of the completed conduit assembly  30  showing components enclosing a channel  46 . Dense fiberglass duct board type insulation  45  is field installed from the inside of the building to snugly fit between composite webs  40  and  41  in the inter-panel space. It preferably has a foil-scrim-kraft, (FSK) laminate  42  on the side facing the channel. The FSK laminate both provides a radiant barrier to reflect heat towards the upper part of the conduit assembly and an aerodynamically rough surface to enhance turbulence in air flow  47 , thus improving convective heat exchange. It is commercially available from CertainTeed, Owens Corning and others in 1″ thickness. 
         [0050]    14. Composite web sections  40  and  41  form the left and right sides of channel  46 . The upper surface of the channel provides the capability to selectively add or remove heat from air flows  47  based on heat flows, arrows  31   a,    31   b  and  31   c,  arising from thermal plane  24 . The upper surface of channel  46  is formed from angle portions  34   b  of flanges  34  and  35 , clips  96  that secure top plate  39  against the flanges, portions of top plate  39  and periodically spaced brackets  95  that prevent clips  96  from moving out of position once secured as shown in  FIGS. 5   a  and  5   b.    
         [0051]    15. All the upper surface components are preferably made from 6063 T5 alloy aluminum extrusions for low cost, light weight and good thermal conductivity. The large extended (wetted) surface at the upper part of the conduit and short distance between laminate  42  and clips  96  serves to decrease the hydraulic radius and increase the velocity of air flows  47  within channel  46 , thus increasing the heat transfer coefficient between conduit  30  and air flow  47 . 
         [0052]    16. A key factor in the heat flow indicated by arrow  31   b  is a good congruence/contact between bulbs  39   b  at the edges of plate  39  and the internal radius (not numbered) of flanges  34  and  35 . Optionally, thermal caulk  104  can also improve heat transfer to conduit  30  from thermal plane  24 . 
         [0053]    17. The thermal plane at the lower part of the panels, illustrated by cross brace  49   b  and interior skin  66  ( FIG. 6   c ) is thus well insulated from the exterior thermal plane  24  comprising cross braces  49 , skin layer  36 / 37  and flanges  34 / 35 . As many of the components of panels  32 / 33  are present in conventional roof decks, but configured differently with appropriate materials in the present invention, this can be achieved at a relatively low cost increment compared to standard construction methods. 
         [0054]    18.  FIGS. 4   a  through  5   d  show the sequence of assembly of the panels to one another and to structural members such as I beam girders  109  and truss joists  119 .  FIG. 4   b  is the completed weatherstrip assembly  25  and structural assembly. In contrast to five passes across the roof deck from the outside common for assembling conventional (stick built) systems buildings, the new system can be assembled as shown in  FIGS. 5   a - 5   d  by workers operating off of a scissors lift from inside the building in two passes across the roof deck. In contrast to driving self-drilling screws through insulation foam into corrugated metal from the outside for flat roof buildings; the roof membrane is not perforated with the new system. The later change has important implications for better fire resistance by eliminating paths for liquefied foam materials to contribute to a fire under ‘flashover’ conditions. 
         [0055]    19.  FIG. 4   a  shows the first step in the assembly sequence of attaching panel  33  to panel  32  in the creation of panel array  21 . Top plate  39  is moved into dovetail shaped channel  34   d  as shown by arrow  28 . Plate  39  has a notched ridge  39   a  at the bottom and bulb portions  39   b  at both edges. Weatherstrip seal  38  has a flat portion  38   b  extending between the bulbs and a flap portion  38   a  at what will become the down-slope side of the joint. Seal  38  is preferably made from a closed cell, fire resistant foam with high compression recovery such as Neoprene™. As plate  39  moves into channel  34   d,  it clears flange bulb  34   c  above and stops when it arrives at the back surface of channel  34   d.  Flat portion  38   b  is slightly compressed between bulb  34   c  and angle portion  34   b  of flange  34  at this point. 
         [0056]    20. Moving to  FIGS. 5   a  through  5   d;  clips  96  are inserted between the lower surface of plate  39  at the down-slope side of joint being formed and temporarily locked in place using a screw driver  99  with a twisting motion of the blade between notched ridge  39   a  and projection  96   a  of the clips. When the shallow notch  96   b  reaches the corner  34   e  of angle portion  34   b  it will click into place. Clip  96  will compress flat portion  38   b  of seal  38  below flange bulb  34   c  and above plate bulb  39   b  to form the primary seal of assembly  25 .  FIG. 5   a  illustrates completed weatherstrip assembly  125 .  FIG. 5   b  illustrates assembly method for clips  96  within the invention.  FIG. 5   c  illustrates structural connection  126  to a sloped roof building girder.  FIG. 5   d  illustrates structural connection  124  to a low slope (flat roof) structural truss joist. 
         [0057]    21. The area of former flat portion  38   b  between these two points is indicated by  38   c  in  FIG. 4   b  and resembles in some ways a compressed o-ring in a circular seal. Flap portion  38   a  comprises the secondary weather strip seal in the case of systems buildings or other sloped roof assemblies. It has not yet been determined if flap portion  38   a  should be used in the case of low pitch flat roof assemblies or if other secondary sealing means should be used. As shown if  FIG. 5   d , panels are oriented perpendicular to truss joists  119  when used in low slope (flat roof) buildings. A pitch of up to 2 inches per foot of run should preferably be used in conjunction with these types of installations. 
         [0058]    22. The temporarily locked exterior components and the structural ties to girders and trusses are established as shown in  FIGS. 5   c  and  5   d  before lifting, placing and engagement of panel  33 . A shortened section of plate material  39 , indicated by  107   b  or  107   a  is welded to a spacers  105  or  105   a  and mounted to a girder  109  or a truss joist  119 . Shorter carriage bolts  106   a  rest in a gap of notched ridge  107   a,  pass through spacer plate  105  and the upper flange of girder  109  (opposite side of upper flange not shown but used) and are loosely secured with nuts  106   b  below the top flange. As with top plate  39 , section  107   b  is temporarily held parallel to the girder flanges by a clip  96 . 
         [0059]    23. The width of the spacers,  105   w,  determines the spacing between panels  32  and  33 . Panel  33  is then lifted up to the roof deck and moved in place, as indicated by arrows  108 . After positioning the new panel, clips  96  are place on the up-slope side of the joint and brackets  95  secured to studs  97  with nuts  98  to secure assembly  25 . The free ends of the clips cannot move downward loosening the contact/seal at area  38   c.  When position into and out of the plane of the drawings is confirmed, bolts  106   a  or longer bolts  106   d  are tightened, locking the panels to building frame components. 
         [0060]    24. Instructions relating to  FIG. 5   c  apply to  FIG. 5   d  with the exception that longer carriage bolt  5   d  is threaded between the upper angle iron parts  119   a  and  119   b  of truss joist  119  and a nut  106   b  and fender washer  106   c  are used to secure the panels. Part  123  is a diagonal brace in truss joist  119 . Without perforating the panels with self-drilling screws the panels can be easily removed and re-used/modified or replaced with alternates. The modular nature, light weight and expandability of the panels from a shipped container like configuration make it ideal for use in refugee or disaster relief around the world. It is also suited for developing country use for village buildings to counter the rising problem of migration to urban slums. 
         [0061]    25.  FIG. 6   c  is a cut-away structural isometric of a daylighting section  68  within a roof mounted panel, such as panel  32  or panel  33 . Bulkhead assemblies  52  delineate the area of the section along the long axis of the panels and are locked into the angle I beam side rails of the panel  34   s  and  35   s.  (Reference U.S. Pat. No. 6,959,520 for Demand Side Management Structures) Stringer sections  53  are anchored to and span the bulkhead assemblies dividing the daylighting section into three compartments. The view is from the exterior of the roof deck and the exterior skin  36 / 37  is cut away to reveal the structure. Exterior skin  36 / 37  in the completed panel covers the entire exterior surface (viewed from the outside) up to the perimeter of exterior glazing  54 . The preferred material for glazing  54  is ¼″ thick acrylic plastic.  FIG. 8   b  provides additional details on surface options. 
         [0062]    26. One key feature of the invention is the use of an exterior glazing at the center compartment in conjunction with an interior pane  55  shown below it in this view. During development work it was found that the IR content of ambient day light passing through the assembly as shown could be cut from 50+% at the exterior to 8-14% infrared in the total light entering the building space below. This greatly reduces the air conditioning load of a building as the vast majority of this load comes from artificial lighting and vertical glazing as shown in  FIGS. 10   a  and  10   b . In turn, artificial lighting and air conditioning load during summer days, (when daylighting can be used) are the straw that breaks the electric grids&#39; back. This is occasionally referred to as ‘the energy crisis’. 
         [0063]    27. Two preferred materials for interior pane  55  are 1″ double lite units of PPG Solarban™ 70XL on Starphire (clear) combined with another lite of Starphire in the first case and a second lite of Atlantica (tinted) 0.25″ thick glass in the second case. There was 0.5″ between the two panes. Atlantica resulted in only 8% IR entering the building envelope while the Starphire resulted in about 14% entering the building. Potent visual evidence supporting this heat rejection was provided by the bright red color emerging from the edges of pane  55  during the day. 
         [0064]    28. Both double pane units had R values of 3.4, which combined with rejection of IR content and removal of warm air flow  65  from the ceiling of the building amount to an extremely significant amount of air conditioning reduction. As detailed in  FIGS. 6   a  and  6   b , the routing and management of air flow  65  across interior pane  55  and conditioning through thermal conduit  30  are two powerful tools for resolving some of ‘the energy crisis’. 
         [0065]    29.  FIG. 6   a  shows functional components applied to the structure shown in  FIG. 6   c .  FIGS. 6   a  and  6   b  together provide a controls  90  and operation logic sequence for the solar, daylighting and night cooling system  100  of the invention. Two small blowers  57  are mounted on the left stringer section  53  in the view. Three small blowers, indicated by dashed arrows from character  57  are located on the right stringer section  53  in the view. 
         [0066]    30. The area indicated at bottom of the left compartment,  64 , is open to the area below the array to allow air flow  65  from below array  21  to readily enter daylighting section  68 . After moving past lighting strip  63  in the left compartment, the pair of two blowers moves this air flow (arrows  56 ) across the surface of interior pane  55 . During daytime operations, IR sourced heat rejected by pane  55  is picked up by the flow and moved towards the three blowers on the right. 
         [0067]    31. Normal stratification in the building will allow much of the heat generated inside building envelope  91  by equipment, other artificial lighting and even the heat generated by the visible light allowed to enter the building to be taken up along with air flow  65 . 
         [0068]    32. A module  60  containing battery storage, controls electronics and power supplies supplies power through the connector (not numbered) at the far left of the view to the two blowers at left. It is mounted on far bulkhead  52 . A near module  60  indicated behind near bulkhead  52  supplies power to the three blowers at the right. 
         [0069]    33. Photovoltaic (PV) strips  60   a  mounted at the interior surfaces of both modules both quantify the amount of natural light available (for switching and control purposes) and supply DC power to the batteries for night operations. Lighting strip  63  is preferably an LED device and can be sourced either from modules  60  and/or ordinary grid supplied AC power. Blowers  57  can be conventional electronic units designed for the higher heats expected to be encountered in the central compartment. 
         [0070]    34. Drying agent cartridge  59  is shown at right and installed per dash dot arrow  59   e  in the right compartment of daylighting section  68 . It has a semi-circular face  59   d  which faces the three blowers mounted on right stringer  53 . Two gasket strips  59   a  and  59   b  separate face  59   d  from a roughly right angle surface  59   b  which faces web portion  40  with two holes (not numbered) connecting the right compartment with conduit assembly  30 . 
         [0071]    35. Cartridge  59  contains a packed bed of drying agent  58  having the characteristic of dehydrating in a flow of warmer air and absorbing moisture from a cooler stream of air. This is desirable to prevent condensation of moisture in air flow  47  during night cooling operation and formation of mold within conduit assembly  30 . Surfaces  59   d  and  59   b  of the cartridge are made from perforated metal or high temperature plastic sheet. Gasket strip  59   a  meets upper skin  36  at the top. Gasket strip  59   b  meets web  40  requiring passage of air flow  56  through cartridge  59  and out through holes  40   a  into channel  46 . 
         [0072]    36. Lower plate  67 , ( FIG. 6   c ) contains movable gates  61  which are part of the overall control scheme ( FIG. 6   b ) and is hinged (not shown) for the normal installation of cartridge  59  from below. Positions of gates  61  are ‘o’ for open and ‘c’ for closed. These are enabled by an actuator, (not shown). The second element of the control scheme, louver(s)  94  in  FIG. 7 , are characterized by the dashed illustration of assembly  30  and plenum  78  at the upper right of  FIG. 6   a.    
         [0073]    37. Positions for louver(s)  94  are ‘I’ for directing flow  47  to the inside of the structure, (shown as ‘ 79 ’ in  FIGS. 1 and 7 ), ‘O’ for directing flow  47  to outside the structure, (shown as ‘ 80 ’ in  FIGS. 1 and 7 ) and ‘X’ for blocking flow through plenum  78  to enable bypass through open gates  61 . The ‘X’ position creates a return flow  99  to the building interior originating at semi-circular face  59   d.  Ideally the lower edges of gates  61 , (not shown) are designed to disrupt some stratification within building envelope  91  using return flow  99 , much like a ceiling fan. 
         [0074]    38. A control logic chart for the operation of solar, daylighting and night cooling system  100  is shown in  FIG. 6   b . While the invention is not limited to this control scheme, it represents a reasonable approach to utilizing the system components in a large number of ordinary applications. 
         [0075]    39. Two control settings/operational modes that are central to functionality of system  100  are: Summer-Day and Winter-Day. In the Summer-Day mode: Interior air flow  65  below panel array  21  carries excess heat from the interior of the building past lighting strip  63  which should be off during peak cooling hours of the summer. Passing over pane  55  moved by fans  57  significant amounts of heat energy arising from IR rejection and some visible light absorption by the pane are gained. This amounts to roughly 53% of the light wattage entering below upper pane  54  in the case of the two lite Starphire™ pane cited above. Roughly 40% of this wattage reaches the interior of the building as visible light. As gates  61  are closed, air flow  47  moves through cartridge  59 , conduit assembly  30  and is vented to the outside, (louvers  94  set at ‘O’). 
         [0076]    40. In the heating season, solar insolation  22  is very roughly 40% of summer values on a daily basis through a typical November to March heating season. A very rough estimate of the visible light content of insolation  22  shows that it could go up to 79% from the 44 to 47% encountered during cooling months due to a higher proportion of diffuse light in the mix. 
         [0077]    41. In the Winter-Day mode of operation: Air flow  65  from just below the ceiling carries artificial lighting heat and equipment heat up past lighting strip  63  which may be partially on, contributing heat to the flow depending on the measurements at PV strips  60   a.  Due to the higher proportion of visible light coming in and the shorter daytime use hours, the amount of visible light entering building envelope  91  will stay about the same. About 42% of solar insolation  22  rejected by pane  55  will be returned by means of fans  57  to within the building via air flow  99  below open gates  61 . Contributions made from lighting strip  63  and heat sourced within the building are returned as well. Louvers  94  are in the ‘X’ closed position enabling this flow. Both the improved insulation of the panels discussed earlier and this return of heat to within the building should provide for a significant reduction of heating demand. 
         [0078]    42. Radiative night sky cooling during the summer can contribute between 250 and 600 W hr of heat sink capacity per night per meter squared of panel array  21  surface to an HVAC system or other refrigeration system within a building. This range does not consider contributions from convective cooling and is arrived at looking at climate data from 30 cities scattered across the country. The Summer-Night mode of operation of system  100  would therefore be important to a number of buildings with high cooling needs such as data centers, hospitals, or supermarkets. 
         [0079]    43. In the Summer-Night mode, operating in early morning hours for best effect, air flow  65  from inside the building passes light strip  63  which is typically off. Little effect occurs passing across the top of pane  55  and blowers  57  force the air through drying agent  58  which has been dehydrated from warmer air passing through during the day. Dry air flow  47  passes through thermal conduit  30  and cools due to heat flows  31   a,    31   b  and  31   c  toward thermal plane  24 . Cooled dry air returns through flow  80  to the interior of the building as louvers  94  are set to the ‘I’ interior positions. 
         [0080]    44. While the description above is for an integral roof mounted array/plenum, a similar mode of operation is possible for potential free-standing arrays described at  FIG. 7 . The same cooling intensive applications described above could also be served by system  100  configured in parking lot arrays or over-roof arrays mounted on top of existing roofing. 
         [0081]    45. In a fire or other extreme weather condition such as a hurricane, it is desirable to vent the air at the interior of the building as much as possible. This removes smoke from the building in the first case and reduces the pressure in the building in the second case, limiting uplift forces on the roof. In the Fire mode, louvers  94  are in the ‘O’ outside position and gates are in the ‘c’ closed position. It would also be desirable to add a whole building blower (not shown), downstream of louvers  94  to enhance this protection. 
         [0082]    46. During some intermediate weather conditions, indicated by the ‘Spr/Fall’ mode, thermal plane  24  could be used to increase heat in the building during the day. Heat acquired passing over pane  55  would add additional solar heat from the thermal pane moving through conduit  30  and be returned to the building with louvers  94  set to the ‘I’ inside flow setting. This mode of operation would also be advantageous to applications where drying of material or crops would occur, e.g. timber dehumidification or tobacco. 
         [0083]    47.  FIG. 7  is an additional process flow diagram that illustrates the operational modes discussed above along with some optional features that are pertinent to other applications e.g. free-standing arrays mounted in parking lots or on roof tops. Solar heat or night sky cooling capacity sourced from thermal plane  24  can be stored in tank  75 , ideally buried beneath the parking lot. 
         [0084]    48. In a free-standing array configuration building envelope  91  does not apply, nor does air flow  79  to inside the building. Louvers  94  are not necessary and all flows  47  emerge from plenum  78  as flow to the exterior  80 . Plenum  78  in this case contains finned heat exchanger  92  having an inner tube  82  within an exterior tube  81  construction. Fins  83  are brazed to the outer tube. This type of exchanger is commonly used in greenhouses and is readily available. 
         [0085]    49. Heat transfer fluid  93   a  is heated or cooled by conditioned air  47  that has passed through thermal conduit  30  and takes a path through exchanger  92  and around fins  83 . Pump  75   a  circulates fluid  93   a  through tank  75  and exchanger  92  via transfer lines  93 . Heat or cooling capacity is stored in thermal media  75   b  within the tank for use in nearby buildings, (not shown). 
         [0086]    50. Cooling capacity is a critical component in the operation of computer server farms which are burgeoning across the world. The additional cooling capacity provided by the free-standing configuration would come at a lower cost than conventional air source heat pumps and would not disrupt the critical operations. Use of optional photovoltaic layers  136  on top of panels such as  33   p  and battery storage (not shown) would add to facility reliability in the event of ever more common power outages. Cooling and emergency power are also critical to operations of hospitals and other operations such as computer server farms, food services and sales. 
         [0087]    51.  FIGS. 8   a  through  8   c  show the structure and mounting of outer glazing  54  shown earlier. As fear of leakage around conventional daylighting curbs is a primary limitation on customer use, establishing a positive, reliable seal around the perimeter as illustrated in the figures is a requirement.  FIG. 9  is an isometric assembly view of an alternate pane  55   a  to that described in earlier figures and a carrier frame  133  for both interior pane  55  and alternate pane  55   a.    
         [0088]    52.  FIG. 8   a  is a top view of panel  32 / FIG. 1  in the area of daylighting section  68 . Compressed insulation  48  is shown filling the space between inside skin  66  of the panel and the outer skin in the compartment adjacent to section  68 , (not numbered). Exterior glazing  54  is seen through exterior film  54   d,  which is laminated around the periphery of the lite to exterior surface  118 . A preferred material for film  54   d  is Arkema 502-CUH-HC (or equivalent) which can be thermally or adhesively bonded to exterior surface  118  when panel  32  is produced at the factory. 502-CUH has a visible transmittance of 95% but absorbs significant amounts of UV light, reducing light aging of materials below it. Film  54   d  provides a reliable seal at the exterior of the roof deck. The lack of such a seal has been a major factor limiting the use of daylighting in buildings of all types. 
         [0089]    53. Perimeter double line  112   c  is shown in  FIG. 8   b  below as the bulb portion of flange  112  at bulkhead  52 , (not shown to scale).  FIG. 8   b  is an assembly drawing of joint  115  between glazing  54  and panel frame members. Flange  112  is basically half of earlier flange type  34 / 35  either made separately or cut from the earlier flanges. Soft gasket  113  is adhesively bonded to the bottom surface of flange  112  and compressed to form a secondary seal when rounded projection  54   a  of outer glazing  54  is pushed against it by plastic clip  129 . Plastic clip  129  is nearly identical to earlier metal clip  96 . Notch  129   b  in the clip is engaged from below by a flat hand tool and urged (arrow  114 ) into the space between angle  112   b  and ledge  54   b  of the glazing. Shallow notch  129  engages the square edge of angle  112   b  and the vertical edge of clip  129 , (not numbered) engages the square edge of ledge  54   b.    
         [0090]    54. As shown in  FIG. 8   c , rounded projection  54   a  is thin compared to the overall thickness of glazing  54  and would likely fail in the completed assembly (as a chemical burst disk would on a pressure vessel) under the larger pressure differentials between the interior and exterior encountered in a hurricane or tornado. This would allow air flow  65  from below the daylighting section to vent air rapidly from inside and prevent uplift of the roof with subsequent failure of the building as a whole. 
         [0091]    55.  FIG. 8   c  is an edge view of glazing  54 . Solar insolation  22  is shown at the right. After passing through the layers of glazing  54 , the light emerges from textured surface  56   c  and is spread from its original linear beam to form a cone of light  121 . Surface  56   c  is illustrated as pyramidal parts separated by planar parts as it may be desirable to have some view of the exterior while also diffusing the light to obtain fairly uniform illumination at floor level in the building. Film  54   d  in this view is shown parallel to the other parts and bonded to acrylic glazing sections  54   e,    54   a  and  54   b  at surface  54   f.  During installation to surface  118  at the outside, flexible film  54   d  would be deformed to fit through the panel aperture defined by  112   c  and then bonded to surface  118 . 
         [0092]    56. The sections listed above are preferably formed by contouring the edges of a single piece of material. After contouring, the edge surfaces at the top of  FIG. 8   c  are preferably polished to allow return of visible light occasionally piped out to the edges by the ‘light pipe’ effect between the lower refractive index  54   d  and the higher refractive index of the other sections. 
         [0093]    57.  FIG. 9  shows the use of a single pane  55   a  as an alternative to the double lite interior pane  55  used in the preceding drawings. The single pane unit would have reduced cost at some detriment to overall performance. Preferential IR reflection and refraction at the upper surface, indicated by  55   c  would be maintained. An optional alternative to placing diffusing surface  54   c  at glazing  54 , diffusing surfaces could be placed below pane  55   a  as indicated by dashed arrow  55   d.    
         [0094]    58. In the final steps of field installation of system  100 , either pane  55  or pane  55   a  is lowered onto carrier frame  131  and it is raised into position below the otherwise completed daylighting section  68 . Hinge fittings  135  engage mating fittings at a structural component of section  68 , and latch  32  is closed against a mating connector on the daylighting section to complete system  100 . 
         [0095]    59. The solar, daylighting and night cooling system  100  overcomes the inherent limitations of prior art systems in dealing with solving the key cooling load problem of lighting contribution to peak loads shown in  FIGS. 10   a  and  10   b . Additionally, it advances the field of daylighting beyond the approaches seen in the state of the art NY Times building in the area of enabling night sky cooling of buildings.