Patent Publication Number: US-2011073163-A1

Title: Photovoltaic lamination and roof mounting systems

Description:
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to the field of photovoltaic modules and associated mounting systems, and more specifically, to light weight photovoltaic laminations and roof mounting systems configured to permit air flow for cooling purposes and which mount to existing roof structure without compromising the sealing integrity of the roof. 
     2. Background of the Invention 
     The drive for renewable energy alternatives has brought about advances in photovoltaic technology, which has been accompanied by the development of installation environments and mounting systems. Photovoltaic modules, commonly referred to as “solar cells” or “solar panels,” have conventionally included a plurality of modules electrically interconnected and encapsulated between various layers of materials, typically glass, metals and adhesives. While glass as a protective cover layer is advantageous in that it is durable and provides rigidity to a panel, it is disadvantageous in that it is heavy, cannot easily be cut to provide custom on-site installations, and breaks typically result in destruction of the entire panel. Further, glass panels absorb heat, which decreases the performance of the panel, and also increase the heat absorption of the roof structure upon which the glass panel in installed. 
     To mount glass-based photovoltaic modules to roof structures, many conventional designs require elaborate, costly mounting systems capable of supporting the weight of the panels. These conventional mounting systems have further commonly required penetrating the roof structure to locate adequate support to attach the mounting systems and glass panels thereto. While the use of solar panels is environmentally conscious and responsible for both residential and commercial applications, compromising the sealing integrity of the underlying roof may potentially offset the advantages of installing solar panels. 
     Accordingly, what is desired are photovoltaic modules and mounting systems that are readily installed, relatively simple in design, inexpensive to manufacture, durable, and do not compromise the sealing integrity of the underlying roof. 
     BRIEF SUMMARY OF THE INVENTION 
     To overcome the disadvantages of prior art photovoltaic modules and roof mounting systems, in various aspects, photovoltaic laminations including non-glass protective layers and associated systems for mounting the laminations to roof structures and other structures are provided herein. 
     In one aspect, a photovoltaic lamination is provided including a non-glass protective layer. 
     In another aspect, a photovoltaic lamination is provided having a high power density. 
     In yet another aspect, a non-glass photovoltaic lamination is provided that absorbs significantly less heat than glass-based photovoltaic modules. 
     In yet another aspect, various roof mounts for non-glass photovoltaic laminations are provided configured to maintain the lamination in a position elevated from the underlying roof, thus allowing air flow between the roof and module for cooling purposes. 
     In yet another aspect, various roof mounts for photovoltaic laminations are provided that mount without penetrating the underlying roof. 
     In yet another aspect, various roof mounts for photovoltaic laminations are provided configured to position the lamination at a predetermined angle with respect to the underlying roof to optimize performance. 
     In yet another aspect, a photovoltaic system is provided including a top component comprising a lamination of a photovoltaic module and a support panel, and a bottom component for securing the top component to an underlying roof. 
     To achieve the foregoing and other aspects and advantages, various embodiments of a photovoltaic lamination and associated roof mounting systems are provided herein. In one embodiment, the system includes a lamination including a photovoltaic module arranged upon a support panel, the support panel defining a generally planar surface for supporting the photovoltaic module and first and second flanges positioned along opposing sides of the support panel and generally perpendicular to the generally planar surface, the first and second flanges extending in the direction away from the photovoltaic module. The system further includes a roof mount underlying the support panel and configured for attachment to an underlying roof, the roof mount including a generally planar base and first and second flanges positioned along opposing sides of the base and generally perpendicular to the base, the first and second flanges of the roof mount extending in the direction toward the support panel. The corresponding flanges of the support panel and the roof mount are aligned and secured together to attach the support panel to the roof mount to position the photovoltaic module in a position elevated from an underlying roof. 
     In another embodiment, each of the first and second flanges of the support panel and roof mount define at least one opening therethrough for receiving a fastener to secure the support panel and the roof mount together. The base of the roof mount may include an open center portion devoid of material or may include one or more flanges positioned on the base and extending upwardly toward the overlying support panel for support and breaking up the airflow beneath the panel. The support panel may define a surface area larger than the surface area of the photovoltaic module. 
     In another embodiment, the first flange of either the support panel or the roof mount has a length greater than its corresponding second flange in order to position the photovoltaic module at an angle with respect to the underlying roof mount and optimize performance. In one embodiment, the preferred angle is about 15 degrees relative to horizontal. In one method of attachment, the first and second flanges of the support panel are received between the first and second flanges of the roof mount. In another embodiment, ends of the first and second flanges of the roof mount extend beyond the length of the generally planar surface and are accessible for receiving at least one clamp for securing the first and second flanges to roof structure, such as to raised seams of the roof. 
     In another embodiment, the photovoltaic module comprises a non-glass protective cover layer, a photovoltaic layer including one or more photovoltaic cells, and a back film layer, wherein the layers are bonded together with layers of adhesive material to form a lamination. 
     In another embodiment, the photovoltaic system includes a support panel defining a generally planar support surface for supporting a photovoltaic module, and first and second flanges positioned along opposing sides of the support panel and generally perpendicular to the support surface, a photovoltaic module secured to the support surface, and a roof mount underlying the support panel and configured for attachment to an underlying roof, the roof mount comprising a base and first and second flanges positioned along opposing sides of the base and generally perpendicular to the base, wherein the first and second flanges of the support panel and the roof mount are aligned and secured together to attach the support panel to the roof mount to position the photovoltaic module in a position elevated from an underlying roof. 
     In another embodiment, a roof mounts are provided including a vertically extending member having first and second flanges extending laterally therefrom forming a channel therebetween for retaining a photovoltaic module, and further including a their flange extending laterally from the vertical member for attaching the roof mount to a roof. The distance between the channel and the third flange is dependent upon the desired height of the photovoltaic module from the roof. 
     Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects and advantages of the present invention are better understood when the following detailed description of the invention is read with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a photovoltaic mounting system including a photovoltaic module, a support panel and a roof mount in accordance with an embodiment of the present invention; 
         FIG. 2  is a detailed perspective view of the photovoltaic mounting system of  FIG. 1  shown installed upon a roof; 
         FIG. 3  is a perspective view of the photovoltaic mounting system shown disassembled; 
         FIG. 4  is a schematic diagram illustrating the layered construction of the photovoltaic lamination; 
         FIG. 5  is a perspective view of the underside of the support panel including flanges and stiffening ribs; 
         FIGS. 6   a - c  illustrate various lamination methods utilizing a metal support block, metal bars and a shaped heating plate, respectively, for imparting flatness to the support panel during the lamination process; 
         FIG. 7  is a perspective view of the system of  FIG. 1  detailing fastening points for receiving conventional fasteners for securing the support panel to the roof mount; 
         FIG. 8  is a perspective view of the roof mount shown removed from the system and including an optional open center devoid of material; 
         FIGS. 9   a - d  illustrate various alternative roof mounts including a frame for retaining the lamination in an elevated position and flanges for attachment to roof structure; 
         FIG. 10  is an alternative embodiment of a mounting system including a roof mount configured to provide a predetermined slope to the photovoltaic module or lamination with respect to the underlying roof to optimize performance; 
         FIG. 11  is an illustration of an alternative embodiment of a roof mount including upwardly projecting flanges operable for supporting the weight of the support panel and reducing the air flow rate beneath the support panel to minimize air lift effort; 
         FIG. 12  is a detailed perspective view of the construction of a center flange of  FIG. 11  made by cutting the roof mount and bending a portion upward to about a 90 degree angle; 
         FIG. 13  is an alternative embodiment of a mounting system including flanges that extend beyond the lamination configured to receive clamps for securing the system to existing seams of the roof; 
         FIG. 14  is a perspective view of the system embodiment of  FIG. 13  shown secured to a roof including raised seams using a plurality of clamps; 
         FIG. 15  is a perspective view of an alternative roof mount embodiment for providing a slope to the lamination, wherein the roof mount includes laterally extending flanges for securing the system to a roof; and 
         FIG. 16  is a side view of the system of  FIG. 15  detailing the slope of the lamination. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which exemplary embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the representative embodiments set forth herein. The exemplary embodiments are provided so that this disclosure will be both thorough and complete, and will fully convey the scope of the invention and enable one of ordinary skill in the art to make, use and practice the invention. Throughout this detailed description, the roof mount components of the systems are described as being mounted upon a roof of a building, however, it is envisioned that the roof mounts and systems provided herein may be installed upon any structure having any surface with only minor modification to the components being required. 
     Referring to  FIGS. 1-3 , a first embodiment of a photovoltaic lamination and associated roof mounting system are shown generally at  20 . The system  20  includes a first component or “top” component including a photovoltaic module  22  arranged upon a support panel  24 . The photovoltaic module  22  includes a plurality of photovoltaic cells arranged to provide a solar panel having any desired dimension and a generally planar surface. The photovoltaic module  22  and support panel  24  are laminated as described in detail below. 
     The support panel  24  as shown defines a surface area slightly larger than that of the photovoltaic module  22 , thus framing the module to provide protection of the module edges. The support panel  24  may have about the same size as the module  22 , such that the maximum amount of surface available is realized for solar collection. The support panel  24  defines a generally planar top surface  26  dimensioned about corresponding to the dimension of the associated photovoltaic module  22 . The support panel  24  defines first and second downwardly extending flanges  28 ,  30  positioned along two opposing sides of the support panel, and preferably along the opposing sides having the greater dimension in embodiments in which the solar panel is not square. The flanges  28 ,  30  are positioned, such as by being bent, at about perpendicular to the top surface  26 . The flanges  28 ,  30  may have any predetermined height based upon the desired distance of the photovoltaic module  22  from the underlying roof. In one example, a height of about one to several inches in envisioned. The height of the flanges  28 ,  30  partly determine the air gap provided between the underside of the support panel and the underlying roof. The length and width dimensions of the support panel  24  correspond to those of the underlying roof mount  32  to which is it secured. 
     The roof mount  32  underlies the support panel  24  and may have the same or a different shape. As shown, the roof mount  32  defines a generally planar base  34  having first and second flanges  36 ,  38  extending upwardly from the base  34  along two sides, again preferably the sides having the greater dimension in embodiments in which the roof mount  32  is not square. The flanges  36 ,  38  are positioned, such as by being bent, about perpendicular to the base  34 . The flanges  36 ,  38  have a height corresponding to that of the first and second flanges  28 ,  30  of the support panel  24  such that the flanges of the support panel  24  seat upon the top surface of the base  34  for support along the length of the sides of the support panel  24 . When the support panel  24  and roof mount  32  are secured together, the first and second flanges  28 ,  30  of the support panel  24  are preferably received between the first and second flanges  36 ,  38  of the roof mount  32  to prevent the flanges of the support panel  24  from directly contacting the roof surface. 
     The material used for the support panel  24  and roof mount  32  may be any rigid material capable of supporting the weight of the photovoltaic module  22  while maintaining its shape throughout the lifespan of the system. Metal is preferable as it may be readily bent to form the flanges and remains rigid regardless of the temperatures ranges likely to be experienced. Suitable examples of metal include galvanized steel and aluminum. As described below, the thickness of the material needed to prevent sagging across the short dimension of the support panel  24  may be reduced as the lamination of the support panel and photovoltaic module imparts rigidity to the support panel. 
     Referring specifically to  FIG. 1 , the support panel  24  is shown ready to be installed upon and secured to the underlying roof mount  32 . Referring specifically to  FIG. 2 , a detailed view of the support panel  24  being partly installed upon the roof mount  32  is illustrated. Referring specifically to  FIG. 3 , the photovoltaic module  22 , support panel  24  and roof mount  32  are shown disassembled. As described in detail below, the support panel  24  may be secured to the roof mount  32  using any conventional fastener, preferably received through corresponding openings defined through aligned flanges. As shown in  FIG. 2 , a pair of the opposing sides of each of the support panel  24  and roof mount  32 , preferably the shorter dimension side, do not include flanges, thus leaving the assembled system open on the ends to permit air to flow therethrough between the support panel  24  and the roof mount  32 . This airflow removes heat from the photovoltaic module  22  thereby increasing performance, as well as prevents/removes heat build up at the roof surface. 
     Referring to  FIG. 4 , the photovoltaic module  22  is constructed from an arrangement of layers to provide the efficient transmission of sunlight upon one or more solar cells encapsulated within the module. The module includes a plurality of layers adhered or bonded together with layers of adhesive material to form a lamination. The module  22  includes a top, transparent, protective cover layer  40  such as a polymer film, adhesive layers  42 ,  44 , photovoltaic layer  46 , and a back film  48 . The cover layer  40  and photovoltaic layer  46  are adhered or bonded with the first adhesive layer  42 . The cover layer  40  faces the sun and serves to protect the module  22  from exterior contaminants, weather conditions and physically applied damage. The underlying photovoltaic layer  46  includes at least one photovoltaic cell associated therewith for directly receiving sunlight and producing electrical current. 
     Suitable examples of protective cover layer materials include, but are not limited to, fluoropolymer films such as ethylene tetrafluoroethylene (ETFE), perfluoro alkoxy, fluorinated ethylene propylene, polyvinylidene fluoride, tetrafluoroethylene hexafluoropropylene vinylidene fluoride, and other fluoropolymer materials such as Tefzel and polyvinyl fluoride (PVF). Additional materials include PMMA, acrylic plastic film, or combined polyfluoro polymer with other plastic film such as polyester (PET/PEN). These types of preferred films are lightweight, flexible or rigid, inexpensive and have excellent weathering performance results. The cover layer  40  may be optically transparent, possess a matte finish or possess a gloss finish. Each of the photovoltaic cells may be a mono-crystalline cell, multi-crystalline cell, amorphous silicone photovoltaic cell, or a compound semiconductor photovoltaic cell. Preferred photovoltaic cells of the module are of the multi-crystalline type due to cost and their ability to sustain a longer period in which to generate electricity. The plurality of photovoltaic cells are connected by suitable electrical conductors connected to a central electrical network, not forming a part of the invention. The cells may be different colored. The cells are encapsulated within the module by the layers described herein. 
     The adhesive layers function to encapsulate the photovoltaic cells and bond to hold layers to form a unitary structure. The adhesive layers preferably include at least one of a thermoplastic polyolefin, a thermoplastic polyurethane, a thermoplastic polyester and a thermoplastic ionomer. Suitable examples of materials comprising the adhesive layers include, but are not limited to, heat-activated adhesives such as the copolymer film ethylene vinyl acetate (EVA), thermoplastic polymers such as XUS® available from Dow Chemical, Surlyn® available from Ionomer, thermoplastic urethanes such as Baeyer&#39;s Dureflex®, and other polyolefin polymers such as ethylene-methyl acrylate copolymer (FMA), silicone resin, and the like. 
     The back film  48  functions to insulate the electrical current generated from the photovoltaic cells, protect the photovoltaic cells from environmental impact, and maintain the structural stability of the cells. A variety of materials may be utilized for a back film protection layer, the most common of which include a polyfluoro polymer sold under the brand name Tedlar® by DuPont. Alternative materials include EPDM film, polyester polymers, and nylon-based and cotton-based films/sheets are also suitable for use in this application. EPE from Madico is a preferred film. Tedlar is preferred as it is chemically and UV-resistant. The back film  48  may have a thickness between about 0.005 inches and about 0.040 inches in an exemplary embodiment. The back film  48  may be colored to suit the proper solar panel application. 
     Referring to  FIG. 5 , the underside of the support panel  24  is illustrated. The support panel  24  functions to provide rigidity to and protect the photovoltaic cells from bending or cracking, as well as protect the photovoltaic module  22  from environmental impact. As shown, the support panel  24  includes laterally spaced-apart stiffening ribs  50  extending parallel to the longitudinal axis of the support layer and to one another. In alternative embodiments, the support panel  24  may include stiffening ribs extending perpendicular to the longitudinal axis or at an angle to the longitudinal axis, or combinations thereof. In one example, the support panel  24  can support a weight load greater than about 45 lbs/sq. ft, and the stiffening ribs may be provided/arranged to achieve this level of support. The support panel  24  may be constructed from an aluminum composite material, steel sheet or other metal or rigid material as mentioned above. 
     Referring to  FIGS. 6   a - c , illustrations of the construction of the lamination of the photovoltaic module  22  and the support panel  24  are shown. A metal block  52 , or metal bars  53  (see  FIG. 6   b ), having a predetermined thickness is applied to the top of the inverted support panel  24  to ensure flatness of the support panel during lamination. To construct the lamination, ETFE film of a predetermined dimension is laid out on a flat surface. A first layer of adhesive is applied on top of the ETFE film. Several string cells are then laid on top of the adhesive. A second layer of adhesive is applied on top of the solar strings followed by a back film/protection layer. A third layer of adhesive is applied on top of the back film, followed by the support panel  24 . The metal block  52  or metal bars  53  is/are then added atop the underside of the support panel  24 . Metal bars  53  are advantageous in that when placed adjacent the flanges and have a corresponding height, they protect the laminator from the sharp flanges by essentially increasing the surface area of the flange in contact with the laminator. Further, bars in contrast to metal block have a lesser volume and thus function as less of a heat sync, resulting in lesser heating times. The stacked layers of plastic, solar cells, support panel  24  and bars or block are placed into the laminator where they undergo a lamination process at a predetermined temperature, time period and pressure. The lamination is then allowed to cool before being removed. The lamination results in a cohesive photovoltaic module/support panel that can then be secured to a roof mount. 
     Referring to  FIG. 6   c , another lamination method is shown. To construct the lamination, support panel  24  is laid out on the heating plate  55  of the laminator with the flanges  28  and  30  positioned downward toward the heating plate. The heating plate  55  defines two elongate channels  57  for receiving the flanges  28  and  30  such that the underside of the support panel  24  is supported directly upon the heating plate to ensure flatness. In other words, the channels  57  provide clearance for the flanges during lamination, ensuring flatness of the support panel and obviating the need for adding/removing a metal block or metal bar that further absorbs heat, increasing lamination time. A first layer of adhesive is laid on top of the support panel  24 . A back film/protection film of a predetermined dimension is laid out on the surface of  24 . A second layer of adhesive is applied to the top of the back film. Several string cells are then laid on top of the adhesive. A third layer of adhesive is applied on top of the solar strings followed by an ETFE film. 
     Referring to  FIGS. 7 and 8 , a plurality of openings  54  are defined through the flanges  28 ,  30 ,  36  and  38  of the corresponding support panel  24  and roof mount  32  for receiving conventional fasteners for securing the components together. The openings are aligned and the components secured together with the fasteners. The system installation method preferably includes first securing the roof mount  32  to the support panel  24 , then securing the roof mount  32  to the roof. In an alternative installation method, the roof mount  32  may first be secured to the roof before attaching the support panel  24 . Fastening may include using mechanical fasteners that may be removed to replace/uninstall a photovoltaic lamination, as well as permanent fastening methods such as welding. Securing the roof mount  32  to the roof may be accomplished using an adhesive, double-sided tape or one of the methods described in detail below. Referring specifically to  FIG. 8 , the center portion of the roof mount  32  indicated at reference number  56  may be open and devoid of material in order to save material, reduce costs and reduce weight. The open center may further be advantageous for installing the system over a protruding structure, further adding to the installation flexibility of the system. The systems of the present invention are advantageous in that installation at the construction site is simplified and the roof is not penetrated. 
     Referring to  FIGS. 9   a - d , various embodiments of alternative roof mounts are shown. Each of the illustrated mounts may be used to replace both the support panel  24  and roof mount  32  of the embodiment described above. Each roof mount is essentially a frame defining flanges forming a channel for retaining the photovoltaic module therein, and an additional flange spaced-apart from the channel forming flanges for being attached to the roof. Although the roof mounts are shown as having a relatively short length, it is intended that the roof mounts may have a length corresponding to the side to which they support, and may include corner supporting portions. To provide installation flexibility, the roof mounts may have a length shorter than the side that they support, allowing an installer to use multiple supports based on the panel size. Thus, a “universal” roof mount is provided. 
     Each roof mount includes a generally vertically extending member  58  having flanges  60 ,  64  extending laterally therefrom. Vertical member  58  may have any height dependent upon the desired distance of the photovoltaic module from the underlying roof. Flanges  60  together define a channel  62  therebetween for receiving and retaining the photovoltaic module. Flange  64  is secured to the roof, such as with double-sided tape or adhesive. In the embodiments shown, flange  64  defines a length longer than flanges  60  to support the photovoltaic module in the elevated position at the preferred slope for maximum sunlight absorption. The roof mounts are preferably constructed from rigid, corrosion-resistant materials. 
     Referring to  FIG. 10 , an alternative embodiment of a photovoltaic lamination and roof mounting system is shown generally at reference number  70 . The photovoltaic module  22  component of the system is essentially the same as described above in detail. The support panel  72  defines a frame  74  around the photovoltaic module  22  and maintains the photovoltaic module therein. Projecting vertically downward from the support panel  72  about one pair of opposing sides of the support panel are flanges  76 ,  78 . One of the flanges  76 ,  78  has a length greater than the other to position the photovoltaic module  22  at a predetermined angle with respect to the generally horizontal underlying roof. In one example, the preferred angle of the photovoltaic module  22  with respect to the underlying roof and horizontal is about 15 degrees for optimal performance. The system  70  further includes horizontally extending base member  80  bridging the gap between and interconnecting the first and second flanges  76 ,  78 . Again, the system is open on opposing ends to permit airflow therethrough for cooling. In embodiments in which the roof has a slope that does not correspond to the preferred slope of the photovoltaic module  22 , the lengths of flanges  76 ,  78  may be customized to position the photovoltaic module  22  at the preferred slope. 
     Referring to  FIG. 11 , a roof mount  32  configured for use with any of the embodiments described herein is shown removed from its overlying support panel and photovoltaic module. The roof mount  32  includes the base  34  which seats upon the roof and first and second flanges  28 ,  30  extending vertically upwardly from the base, such as about perpendicular to the base. Defined within about the center of the base  34  are internal flanges  82 ,  84  that are cut from the base and bent to about perpendicular thereto. The flanges  82 ,  84  function to aid in supporting the weight of the photovoltaic module, as well as reduce the airflow rate through the system to minimize the air lift effort. Thus, flanges  82 ,  84  may be strategically placed beneath the overlying support panel and may have a length corresponding to the length of flanges  28  and  30 . As shown, flanges  82  are centrally positioned on the base  34  and flanges  84  are positioned radially around the center. It is envisioned that the flanges  82 ,  84  may have any length, and may be cut from and bent upwardly or a component added to the base and secured thereto. Referring to  FIG. 12 , a detailed view of a flange  82  is shown projecting from the base  34  illustrating the material void  86  left in the base  34  when the flange  82  is bent upwardly. 
     Referring to  FIGS. 13-14 , another embodiment of a photovoltaic lamination and roof mounting system is shown generally at reference number  90 . The voltaic module  22  component of the system is essentially the same as described above in detail. The photovoltaic module  22  and support panel  24  lamination has a length less than the underlying roof mount  32  such that the ends of the flanges  36 ,  38  are exposed to receive mounting clamps  92  for securing the system to the underlying roof. As shown installed in  FIG. 14 , the underlying roof is of the type having roof panels intersecting at upwardly extending seams to reduce the potentially for leaks. The system  90  installs between adjacent seams with the flanges of the system  90  positioned adjacent the seams and clamped thereto with clamps  92 . Clamp  92  defines a general C-shape having openings defined through opposing sides for receiving a conventional fastener. In one embodiment, the clamp is positioned over the seam and flange and a fastener is received therethrough. In an installation in which the fastener penetrates the roof, it is preferred that the penetration be through the upwardly extending seam in order to minimize the potential for leaking. Clamps  92  may be positioned at one or more of the corners to secure the system  90  to the roof. The support panel/photovoltaic module lamination may be produced with a width corresponding to the distance between seams. 
     Referring to  FIGS. 15-16 , another embodiment of a photovoltaic lamination and roof mounting system is shown generally at reference number  100 . The photovoltaic module  22  component of the system is essentially the same as described above in detail. The photovoltaic module  22  and support panel  24  are supported upon flanges  102 ,  104  that extend downward to be secured to the roof. At the base of each flange  102 ,  104 , flanges  106  extend laterally therefrom to provide an adequate surface area for mounting to the roof and supporting the weight of the system  100 . As in the previous embodiments, the flanges  102 ,  104  may have different lengths in order to provide a predetermined slope to the photovoltaic module  22  when mounted. This embodiment reduced the amount of material as compared to the embodiments shown in  FIG. 10  in which the base covers the entire area underlying the support panel/photovoltaic module lamination. This embodiment may be further advantageously installed on rooftops or other structure that do not have a planar surface area large enough to accommodate the base  80  of  FIG. 10 . 
     While photovoltaic modules and associated roof mounting systems and methods have been described with reference to specific embodiments and examples, it is envisioned that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description of the preferred embodiments of the invention and best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation. 
     Experimental Results 
     Experiment #1. The lamination of a 140 W solar panel having a panel size of approximately 42″×39″ was performed. ETFE film (5 mil) was laid out on a flat surface. A first layer of XUS film (15 mil) was applied on top of the ETFE film. Several string cells were then laid on top of the XUS film. A second layer of XUS film was applied on top of the solar strings followed by an EPE (10 mil) layer, or a back protection sheet. The third layer of XUS film was applied on top of the back protection sheet. The support panel was added last. The metal block was added atop the underside of the support panel. The stacked layers of plastic, solar cells and substrate panel were placed into a laminator and underwent a lamination process at about 150 degrees C. for approximately 5 minutes an under 1 atmosphere of pressure (14.7 psi). The compressed solar panel was removed from the laminator after 5 minutes. The solar panel lamination was secured to the roof mount, which had been adhered to the roofing membrane at the installation site. 
     Experiment #2. The lamination of an 80 W solar panel having a panel size of approximately 70″×15″ was performed. First, the support panel was properly positioned on top of the heating plate of the laminator. A first layer of XUS film (15 mil) was laid on the surface of the support panel. An EPE (10 mil) layer, or a back protection sheet was laid out on a flat surface of the support panel. A second layer of XUS film (15 mil) was applied on top of the back protection sheet. Several string cells were then laid on top of the XUS film. A third layer of XUS film was applied on top of the solar strings followed by an ETFE film (5 mil) which was the last film added. The stacked layers of plastic, solar cells and substrate panel were placed into a laminator and underwent a lamination process at about 150 degrees C. for approximately 5 minutes an under 1 atmosphere of pressure (14.7 psi). The compressed solar panel was removed from the laminator after 5 minutes. The solar panel lamination was secured to the roof mount, which had been adhered to the roofing membrane at the installation site.