Patent Publication Number: US-2005141153-A1

Title: Solar tile assembly

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
      This application is a continuation of U.S. patent application Ser. No. 09/980,471, filed Mar. 26, 2002, which is the national stage of International Patent Application No. PCT/GB00/02159, filed Jun. 14, 2000, the disclosures of which are hereby expressly incorporated by reference. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates to a solar tile assembly and is concerned particularly with a two part solar roofing tile and a method for providing electrical connection between the respective parts of the two part solar roofing tile.  
     BACKGROUND OF THE INVENTION  
      It is known to use solar panels comprising photovoltaic modules that may be placed onto the exterior of a building or replace the existing roof tiles. Examples of such photovoltaic modules are described in U.S. Pat. No. 5,590,495, U.S. Pat. No. 5,112,408 and EP 0710806. The photovoltaic modules systems normally comprise a plurality of solar panels that are electrically connected to form a circuit. The solar panels may require routine maintenance that necessitates the removal of one or more of the solar panels.  
     SUMMARY OF THE INVENTION  
      According to a first aspect of the present invention there is provided a solar tile assembly comprising a removable outer panel that comprises photovoltaic means and a first electrical connector, and an inner support structure that comprises a second electrical connector, the arrangement being such that in use an electrical connection between the first electrical connector and the second electrical connector is achieved by bringing together the outer panel and the inner support structure.  
      The electrical connection between the first electrical connector and the second electrical connector is preferably broken by the removal of the outer panel from the inner support structure.  
      Preferably, the outer panel is slidably attached to the inner support structure by attachment means comprising a channel section formed to receive an attachment element.  
      Preferably, the outer panel comprises the attachment element and the inner support structure is formed with the channel for receiving and retaining the attachment element of the outer panel.  
      The outer panel conveniently comprises a pair of attachment elements and the inner support structure is formed with a pair of channels for receiving and retaining the attachment elements of the outer panel.  
      The electrical connection between the first electrical connector and the second electrical connector is preferably broken by sliding the outer panel in a direction that is substantially parallel to plane of outermost surface of the outer panel.  
      Preferably the outer panel is removed from the inner support structure by first sliding the outer panel in a direction that is substantially parallel to plane of outermost surface of the outer panel and then lifting the outer panel in a direction perpendicular to the direction of the slide direction.  
      In use the inner support structure can be attached to the outer surface of a structure such as a building. If necessary a damaged outer panel can be easily removed from the solar tile assembly whilst still leaving the inner support structure fixed to the building. A new outer panel can then replace the damaged outer panel. Also, the outer panel and the inner support structure can be easily inspected by removing the outer panel.  
      The inner support structure preferably comprises an electrical junction box comprising the second electrical connector.  
      The electrical junction box of the inner support structure preferably comprises an electrical input terminal and an electrical output terminal, the arrangement being such that the electrical input terminal and the electrical output terminal provide electrical communication between corresponding solar tile assemblies. In use the photovoltaic means of the respective solar assemblies generate electrical energy and there may be an electrical network provided between the plurality of solar title assemblies.  
      It is preferable that the outer panel comprises an electrical junction box formed with the first electrical connector, the arrangement being such that in the assembled state of the solar tile assembly the first connector and the second connector provide electrical communication between the two electrical junction boxes.  
      The solar tile assemblies may be conveniently fixed to roof battens of a conventional roof structure and may replace the roofing tiles.  
      According to an embodiment of the first invention the support structure comprises means for providing electrical connections between adjacent solar tile assemblies.  
      The means for providing electrical connections between adjacent solar tile assemblies preferably comprises an electrical connector on opposite sides of the support structure.  
      According to a second aspect of the present invention there is provided a removable solar tile comprising photovoltaic means and an electrical connector, the arrangement being such that in use an electrical connection between the electrical connector of the removable solar tile and a second electrical connector of an inner support structure is achieved by the bringing together of the outer panel and the inner support structure.  
      According to a third aspect of the present invention there is provided an inner support structure for a removable tile comprising photovoltaic means, the inner support structure comprising an electrical connector, the arrangement being such that in use an electrical connection between the electrical connector of the inner support structure and an electrical connector of the removable tile is achieved by the bringing together of the removable tile and the inner support structure.  
      According to a fourth aspect of the present invention there is provided a method for providing an electrical connection for a solar tile assembly comprising a removable outer panel that comprises photovoltaic means and a first electrical connector, and an inner support structure that comprises a second electrical connector, the method comprises sliding the outer panel towards the inner support structure in a direction substantially parallel to the plane of the outer panel until the first electrical connector contacts the second electrical connector.  
      Preferably the electrical connection between the respective parts of the solar tile assembly is broken by sliding the outer panel in the opposite direction.  
      The invention may include any combination of the features or limitations referred to herein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The invention can be put into practice is various ways, but an embodiment will now be described by way of example only with reference to the accompanying drawings in which:  
       FIG. 1  is an isometric view of a solar tile assembly in a closed assembled condition;  
       FIG. 2  is an isometric view of the solar tile assembly shown in  FIG. 1  and shows the assembly in a partially open condition;  
       FIG. 3  is an isometric view of the solar tile assembly shown in  FIG. 1  and shows the outer panel separated from the inner support frame;  
       FIG. 4  is an isometric view of the solar tile assembly shown in  FIG. 1  and shows the outer panel removed from the inner support frame; and  
       FIG. 5  is an isometric view of the solar tile assembly shown in  FIG. 1  and shows more detail of a variable gauge clip, more detail of the outer panel structure and three partial cut-away sections of the outer panel. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      With reference to the FIGS.  1  to  5 , a solar tile assembly  1 A comprises a removable rectangular outer panel  1  that comprises ten photovoltaic cells  3  disposed on the outermost surface thereof, and a substantially rectangular inner support structure  2 . The photovoltaic cells  3  cover the lower portion of the outer panel  1 . Any suitable photovoltaic means may be used for the solar tile assembly.  
      The outer panel  1  is secured to the inner support structure  2  using two fasteners  5   a ,  5   b  disposed at the front end of the solar tile assembly  1 A. The fasteners  5   a ,  5   b  may typically be quarter or half turn captive fasteners. These types of fasteners have the added advantage of being retained by the outer panel  1  during assembly/disassembly processes.  
      The inner support structure  2  comprises a framework at one of which there is formed a lower stepped interlockable section  4 . In use the interlockable section  4  is disposed under a portion of an adjacent tile assembly, as is well known in the art of roof tile design. The inner support structure  2  is formed with three sets of holes  6 . These holes  6  allow fixing nails or screws to be used to attach the inner structure  2  to roof tiling battens located underneath the inner structure  2 . For certain roof designs no fixing nails or screws will be needed to hold the tile assembly  1 A onto the roof. Disposed within the frame of the support structure  2  there is an electrical junction box  7 . The inner support structure  2  comprises two parallel end members  7   a ,  7   b  (shown in FIGS.  3  to  5 ). Formed within each of the respective end members  7   a ,  7   b  there are respective slide channels  8   a ,  8   b . At one end of the slide channel  8   a  there is formed a cutaway access port  9   a . At the corresponding end of the slide channel  8   b  (not shown) there is formed a cutaway access port  9   b.    
      The outer panel  1  comprises a pair of attachment elements  17   a ,  17   b  fixed to the inner surface of the outer panel  1  (see  FIG. 5 ). The attachment elements  17   a ,  17   b  are a triangular wedge shape. A heel portion  17   c  extends from each of the respective vertical faces of the wedge shapes. The attachment elements  17   a ,  17   b  are shaped to be received by the access ports  9   a ,  9   b.    
      Also formed in the inner support structure  2  there are two substantially parallel channels  10  (shown in  FIGS. 4 and 5 ). At one end of each channel  10  there is provided an access port  10   a ,  10   b . Each port  10   a ,  10   b  has a greater width than the width of the remaining portions of the respective channels  10 . The ports  10   a ,  10   b  provide access to the channels  10  for two variable gauge clips  11   a ,  11   b.    
      It will be appreciated by the skilled person in the art that the channels  10  may be used in place of the slide channels  8   a ,  8   b . Channels  10  can operate to perform the function of channels  8   a ,  8   b  by comprising two sets of slide fixtures, one set being attached to the outer panel  1 .  
      Should added retention for the solar tile assembly be required, for example in high winds, the clips  11   a ,  11   b  may slide along the channels  10  and are used to fix the outer panel  1  to an outer panel of an adjacent solar panel assembly located below.  
      The electrical junction box  7  of the inner support structure  2  comprises a pair of electrical connectors  13 , an electrical output lead  14  and an electrical input connector  15 . The outer panel  1  comprises an electrical junction box  19  that comprises a pair of electrical connectors  19   a . In the assembled closed condition off the solar tile assembly  1 A (as shown in  FIG. 1 ) the electrical connectors  13  are in electrical contact with the electrical connectors  19   a.    
      To disassemble the solar tile assembly  1 A the outer panel  1  is first slid in a direction Z and this causes a break in the electrical connection between the connectors  13  and the connectors  19   a . The outer panel  1  is slid in the direction Z until the attachment elements  17   a ,  17   b  abut the respective lowermost ends of the channels  10 . The outer panel  1  will stay in this position without sliding completely off the support structure  2  (as shown in  FIG. 2 ). In order to separate the outer panel  1  from the inner support structure  2  the outer panel  1  is moved back a small distance in the opposite direction to direction Z until the attachment elements  17   a ,  17   b  align with the respective access ports  9   a ,  9   b . The outer panel  1  can then be lifted away from the inner support structure  2  (as shown in  FIG. 3 ).  
      When the solar tile assembly  1 A is reassembled and the outer panel  1  is slid back up into position, the inwardly-extending lip  20  on the front underside of the outer panel  1  fits under a recess  12  that is formed in the lowermost edge of the inner support structure  2  so providing secure anchorage against high wind.  
      The outer panel  1  is constructed typically of two planar sheets of material (see  FIG. 5 ). The uppermost sheet is a transparent material  22   a  that permits sunlight to reach the photovoltaic elements. In the embodiment shown, the uppermost sheet  22   a  is larger on three sides than the lowermost sheet  22   b  and all the fixing arrangements are mounted underneath and inside this area. Hence, no joints exist which could cause water ingress when exposed to the weather. The materials that may be used for the construction of the parts of the solar tile assembly  1 A include metallic or non-metallic including plastics, glass, metal and ceramics/clay/cement.  
      The underside of the inner support structure  2  has location points to allow it to be easily positioned on the roof of a building and also to retain it in position whilst fixing down. The variable gauge clips  11   a ,  11   b  may be used to fix the outer panel  1  to a tile assembly located in a row below, should added retention be required for example in high wind speed areas.  
      The electrical connection between the outer panel  1  and the inner support structure  2  of the solar tile assembly  1 A is made as the outer panel  1  is assembled onto the inner support structure  2 . The electrical connection between the outer panel  1  and the inner support structure  2  of the solar tile assembly  1 A is broken as the outer panel  1  is disassembled from the inner support structure  2 .  
      It will be noted by those skilled in the art that electrical connection between the outer panel  1  and the inner support structure  2  can be broken without the complete separation of the parts because the outer panel  1  has a sliding arrangement with the inner support structure  2 .  
      When the solar tile assembly  1 A is assembled, the electrical connection between the connectors  13  and the connectors  19   a  is retained by use of fasteners  5   a ,  5   b  located on the front edge of the outer panel  1 . When the fasteners  5   a ,  5   b  are undone and outer panel  1  is released the electrical connection will be broken as the outer panel  1  slides in direction Z. When the outer panel  1  stops at the lower part off the channels  10  the junction box  7  will be exposed, therefore allowing access to all necessary electrical components.  
      Flying leads  14  may be used to connect adjacent solar tile assemblies together to complete a circuit. Fixed connections  16  may also be used on the sides of the inner support structure  2  such that as a solar tile assembly is positioned adjacent to another solar tile assembly, an electrical connection can be made because the two parts of the connector  16  (male and female) are integral with the parts of adjacent tiles assemblies.  
      As a row of tile assemblies is completed in the horizontal plane and the next row started, a cable would normally have to run from the end of the last row along the roof to the start of the second row. This uses a considerable amount of cable and therefore incurs electrical losses. An alternative arrangement may be made where the wiring of the connections is reversed in alternate rows. The end tile assembly can then be directly connected with a short wire to the next row above or below. In order to distinguish between the tile assemblies with the two types of wiring, the inner support structure  2  of the tile assembly may be colour coded so that during assembly it is easy to lay alternative rows with the correct wiring arrangement.  
      The dimensions of the solar panel assembly  1 A can be made to correspond with the dimensions of conventional roof tiles. Hence, the solar tile assembly can be easily fitted onto an existing roof. The roof may be partially covered by an array of solar tile assemblies and partially covered by conventional roof tiles. Due to the construction and configuration of the solar rile assembly  1 A, the outer panel  1  of an assembly  1 A can be removed from the array of assemblies without disturbing the other assemblies.  
      When there is an array of assemblies, the upper portion  40  of the outer panel  1  that is not formed with photovoltaic cells  3  because this area is normally covered by a lower portion of an upper adjacent solar tile assembly.  
      It will be appreciated that the solar tile assembly can be attached to any suitable structure outside or inside a building.