MOBILE PHOTOVOLTAIC PANEL STRUCTURE AND ASSEMBLY
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present invention is a Non-provisional Application of U.S. Provisional
Application Serial Number 61/205,951, entitled "MOBILE PHOTOVOLTAIC PANEL STRUCTURE AND ASSEMBLY" filed January 26, 2009, which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a mobile panel support structure for supporting photovoltaic panels or panel arrays installed on buildings. The mobile structure permits relocation of the panel(s) for easy maintenance, repair or replacement of the underlying substrate.
BACKGROUND OF THE INVENTION
[0003] In cases where photovoltaic (PV) panels or arrays are installed on a roof the panels prevent access to maintain or replace the underlying substrate or roof system. If the panels/array have to be disassembled along with the racking system, the electrical system has to be taken off line, resulting in a loss of power generation. Most roofs require 5-15 service calls in a span of 1 - 3 years at the end of their life cycle prior to replacement. One manufacturer of panels estimates maintenance costs to be as high as $0.60 to over $1.00 per watt. What is needed is an easy method of relocating the panels for the necessary maintenance.
SUMMARY OF THE INVENTION
[0004] According to the invention, there is provided a mobile photovoltaic panel support assembly, as defined in claims 1 - 20.
[0005] The present invention solves the above problem by providing a mobile panel support structure for a PV panel or panel array that permits the panel(s) to be quickly moved, lifted, or tilted to allow maintenance, repair, or replacement of the underlying areas, without
disassembling the array components or interrupting power generation. Lifting or folding the racking system permits minor maintenance on the roof system without the need for complete removal of the panel array.
[0006] For a better understanding of the present invention, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention is illustratively shown and described in reference to the accompanying drawings, in which:
[0008] Figures 1-6 are illustrations of photovoltaic panel flat structure supports, lifting and moving mechanisms.
[0009] Figure 7 are illustrates of various embodiments of the present invention in the which panels are tilted at different angles;
[0010] Figure 8 is an illustration of an embodiment of a photovoltaic panel array flat structure system with three separate mobile panel support structures indicating a placement of lifting mechanism assemblies;
[0011] Figure 9 is an illustration of an example of photovoltaic panel array flat structure system relocation schematic;
[0012] Figure 10 is an illustration of an example of a ballast and ballast tray configuration for a photovoltaic panel array flat structure system;
[0013] Figure 1 1 is an illustration of an example of photovoltaic panel array flat structure system; and
[0014] Figures 12-14 are illustrations of embodiment of photovoltaic panel array tilting and storage mechanisms.
DETAILED DESCRIPTION OF THE INVENTION
[0015] As used herein in the specification and claims, including as used in the examples and unless otherwise expressly specified, all numbers may be read as if prefaced by the word "about", even if the term does not expressly appear. Also, any numerical range recited herein is intended to include all sub-ranges subsumed therein.
[0016] The present invention of a solar array or panel rack system IA (Fig. 1), I B (Fig.
2) includes a mobile panel support structure 2 in removable engagement with a pedestal 10 secured to roof 15 by bearing plate assembly 13A (Fig. 1), 13B (Fig. 2).
[0017] One embodiment of the mobile panel support structure 2 of the present invention is shown in Figs. 1 and 2 including a plate 4 attached to end 5 of support post 6 at joint 8 by conventional attachment means such as a continuous weld, where support post 6 slidable engages pedestal 10 for installation and detachment purposes of the solar array structure 7 attachable to plate 4, and pedestal 10 is attached to a flat structure 15, such as a roof. Pedestal 10 can be attached to a bearing plate 1 1 B (Fig. 2) that is directly attached to the flat structure or a bearing plate assembly 13A (Fig. 1). Support post 6 can have a small outer diameter 12 than an inner diameter 14 of pedestal 10 as shown in Figs. 1 and 2 such that support post 6 freely slides within pedestal 10 for quick removal and insertion of support post 6. Another embodiment of the engagement between support post 6 and pedestal 10 can include a support post 6 with a large outer diameter than an inner diameter of pedestal (non-shown). The support post bottom 16 can rest on the platform 18A (Fig. 1), 18B (Fig. 2) where the weight of the solar arrays or panels, plates 4, and support posts 6 are sufficient to be retained in place under maximum normal wind conditions. A securement mechanism can be included for further assurance that the solar array or panel will not lift off the pedestals 10 during extreme wind conditions such as a hurricane or tornado. One example of a securement mechanism is a quick-release connection including a bolt (with or without a nut) or pin 20 and cooperating hole 22, 24 of the support post 6 and pedestal 10, respectively, sized to receive cotter pin 20. The support post bottom 16 does not have to rest on platform 18 where the shear load strength or capacity of bolt or cotter pin 20 is sufficient to sustain the weight of the solar arrays or panels, plates 4, and support posts 6. An alternative embodiment of the support post 6 includes a plurality of securement mechanism cooperating
holes 22 along length L of support post 6 for height H adjustment of the solar arrays or panels 7 above flat structure 15.
[0018] Plate 4 and support post 6 of the present invention can be made from metal (such as aluminum), thermoplastic, electrometric, fiber composite, or any combination thereof having sufficient physical and structural properties.
[0019] Securement mechanisms like pin 20 can be classified as quick-release mechanisms. Other suitable quick-release mechanism for the present invention includes cotter pins, threaded fittings, cam lock, paddle latches, pivot pawl latches, slotted cam latches, T handle latches, or other similar components.
[0020] Bearing plate assembly 13 A can be attached to roof 15 as shown in Figure 1.
Bearing plate assembly 13A can be a plurality of components including bearing plate 1 1 , Platform 18A, fasteners 26, and roof attachment device 28. Roof attachment device 28 can be secured to flat structure 15 directly with a single or multiple fasteners 30. Fasteners 30 can be screws (as shown in Figs. 1-6) or commercially available fasteners or other suitable devices (not shown). Roof attachment device 28 is slidably engageable with platform 18A using conventional sliding mechanisms (such as dovetail/groove configuration shown in Fig. 1 ) to provide for easy removal of platform 18A. Bearing plate 1 IA includes a base width Wl . Roof attachment device 28 includes a base width W2. Base width Wl being larger then base width W2 provides for greater lateral stability of solar array or panel rack system IA. Therefore, base width Wl does not have to be sized for stability can be sized to provide maximum expose of roof 15 without the detachment of roof attachment device 28.
[0021] Bearing plate assembly 13B can be attached to roof 15 as illustrated in Fig. 2.
Bearing plate assembly 13B can be a single integrated component including bearing plate 1 I B, platform 18B, and roof attachment device 28. Platform 18B can be secured to flat structure 15 directly with a double row of fasteners 30. Bearing plate 1 I B includes a base width W3. Base width W3 is sized for lateral stability of solar array or panel rack system I B, which can be greater than the base width W2 of roof attachment device 28 with the same sized solar array or panel rack system.
[0022] Thus, mobile panel support structure 2 with or without solar array structure 7 attached to plate 4 can be easily lifted as an entire array (after disconnecting the support posts) vertically with the lifting device to temporarily removed from pedestal 10 so that the underlying roof area can be accessed. Further, bearing plate assembly 13A can be removed if a roof portion less than the entirety of roof 15 needs maintenance. Roof attachment device 28 and bearing plate assembly 13A can be removed if the entire roof 15 needs maintenance.
[0023] Now turning to Fig. 10, alternative solar array or panel rack systems (not shown) may be laid on the roof and held in place with ballasts 32 in ballast pans 34 or by its own weight without being fastened to roof 15. Ballast for PV panels is well known in the art, and is used to provide a counter-weight in windy conditions to prevent panels/racks from becoming dislodged. In one embodiment, the mobile panel support structure includes a mechanism for utilizing ballast to secure the racking against wind loads. The ballast can take the form of stones, concrete pavers or blocks, sand, liquids, or other materials of sufficient weight. Appropriate vessels (hoses, trays, containers, etc) for holding the ballast are incorporated into the rack and/or support structure, for example, as trays on the underneath side of a panel.
[0024] Now turning to Figs. 3-6, further embodiments of the present invention include jacking or lifting mechanism 36 attached by mounting brackets 44 to a mount bracket 38 of the solar array or panel rack system 1 to raise solar array or panel rack system 1 vertically to any desired height H2 to lift the solar array or panel rack system 1 off pedestal 10 and bearing plate assemblies 13 A, 13B. In Fig. 5, the wheel 42 can be lowered or caster support extended, as in operation, for example, by lifting mechanism 36 to raise the racking system off its attachment to the structure and the entire array (racking system included) can be collapsed to expose the underlying area. This allows limited movement of the array for minor maintenance.
[0025] In an additional embodiment, the present invention comprises additional mounting plates, clamps, attachments to solar array or panel rack system 1 that allow insertion of cradles with locking pins for attachment of at least one wheel, skid, or other device that permits rolling or sliding of solar array or panel rack system 1 , to move solar array or panel rack system 1 to another location of roof 15 without damaging the roof substrate, disassembling the array components, or interrupting power generation.
[0026] The jacking or lifting mechanism 36 can be, for example, via a lever jack, pneumatic jack, screw jack, hydraulic jack, inflating a pneumatic tire, or other lifting means. Additional embodiments of the present invention can include both the jacking or lifting mechanism 36 and quick-release mechanism 20 for lifting and removing solar array or panel rack system 1. One embodiment of the jacking or lifting mechanism 36 includes a castor assembly 40 and wheel 42 to ease of movement of solar array or panel rack system 1 around roof 15 once support post 6 is fully disengaged from pedestal 10 (Figs. 5 and 6) when solar array or panel rack system 1 is lifted to height H2 providing clearance C between support post base 16 and pedestal top 48. One embodiment of the jacking or lifting mechanism 36 includes a pivotal mount 46 that locks substantially parallel with solar array or panel rack system 1 (Fig. 4) to move the jacking or lifting mechanism 36 out of the way when the solar array or panel rack system 1 is in position. Jacking or lifting mechanism 36 pivots along a path of rotation from actuated position to rest position.
[0027] Electrical connections (not shown) with pigtails of sufficient length allow movement of solar array or panel rack system 1 while maintenance is being performed to the underlying substrate, panels, or racking system while still generating energy.
[0028] Now turning to Figs. 7, 12, 13, and 14, one embodiment of solar array or panel rack system 1 includes a mechanism for tilting and/or lifting the racking system and photovoltaic panels vertically to allow maintenance of areas under the racking system.
[0029] Fig. 7 illustrates solar array or panel rack system 1 being tilted 30 degrees, 20 degrees, and 10 degrees. Tilting one or more individual panels address problems of limited scope of access under one or more panels. There is no need to disconnect the support posts for this access.
[0030] Fig. 12 illustrates photovoltaic panels 52 pivotally attached at pivot point 50 to frame 58. Photovoltaic panels 52 are held at a predetermined tilt angle α based on length L of support post 52 and connect point 56.
[0031] Fig. 13 illustrates a foldable rack support 69 including hinged sections 78 connected by articulating mechanism 60 that fold up accordion style. Articulating mechanism 60
can include a hinge, ratchet, or other device near the mid point 80 of the main members 82 of a row 84 related to the array rows 86. Photovoltaic panels 54 can be fixedly or pivotally attached at pivot point 76 to photovoltaic panel support assembly 66. Photovoltaic panel support assembly 66 that are attached pivotal with, for example, a hinge at the front 64 that allows photovoltaic panel support assembly 66 to tilt up so the main frame 58 can collapse. Support post 52 connect to foldable rack support 69 at disconnect point 78. The pivot angle γ can be an angle from 0° to 90°. Other embodiments of the foldable rack support 69 provide a panel support structure comprising for moving or rolling device 72, such as at least one wheel, skid, or other device, attached to alternating articulating mechanisms 60 that can facilitate folding accordion style and moving the foldable rack support 69 without damaging the substrate or disassembling the array components. The plurality of hinged sections 74 can be locked together to form a ridge frame 71.
[0032] Another embodiment of the present invention is illustrated in Fig. 14 tilts the entire array by a hinge mechanism attached to the front or rear of the rack. Tilting the entire rack to the near vertical position allows access for repair or maintenance below a large section of the panel array. The array tilt embodiment includes support post 62 with a hinge at one end of frame 50 and a detachable support post 68 at the other end of frame 50 enabling the pivot of frame 50 to an angle β vertical or near vertical position for routine maintenance. Frame 50 includes pivotal photovoltaic panel support assembly 66 with photovoltaic panel 54. The solar array or panel rack system 1 can be ballasted and wheels/skids 72 can be attached prior to folding.
[0033] Now turning to Figs. 8, 9, and 1 1 that illustrate examples of a plurality of solar array or panel rack systems 1 of the present invention arranged in various configurations for flat structures. Fig. 8 illustrates three (3 - 3 by 1) solar array or panel rack systems 1 , each including six (6) rows of mobile panel support structures 2 attached to frame member 58. Lifting mechanism 36 attachment locations to frame 58 are also shown. Each solar array or panel rack system 1 and mobile panel support structure 2 can include lifting and/or tilting mechanisms discussed above. Fig. 9 is an example of the installation of the present invention on a flat structure. A plurality of solar array or panel rack systems 1 illustrated in Fig. 8 can be laid out or arranged with at least one open space 88 sized to accommodate a solar array or panel rack system 1 when it is moved from its initial position. Arrows indicated in Fig. 9 are examples of
solar array or panel rack system 1 relocation direction. As a solar array or panel rack systems 1 is moved to an open space, it creates an open space to enable movement or relocation of adjacent solar array or panel rack system 1 thereto. Fig. 9 also illustrates that solar array or panel rack systems 1 can be arranged by tilt angle (such as 0°, 5°, 10°, 20°, 30°) in different array sections 9OA, 9OB, 9OC, 9OD, 9OE. The tilt angles can be determined based on latitudinal/longitudinal coordinates and time of year. Fig. 1 1 illustrates twenty-four (24 - 6 by 4) solar array or panel rack systems 1 , each including six (6) mobile panel support structures 2 attached to frame member 58.
[0034] Any of the embodiments of solar array or panel rack system 1 discussed above can be folded and all attachment points released allowing the entire array to be lifted off the roof, placed on a trailer, and moved to another location.
[0035] In some embodiments the racking system includes a commercially available mechanism to allow tracking of the sun's movement to ensure maximum irradiation. Tracking systems are well-known, and the various embodiments of the present invention can be designed for use on an array having such a system.
[0036] The invention is preferably designed as an integral part of a new racking system, but can also be attached to an existing racking system.
[0037] While the disclosure has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the embodiments. Thus, it is intended that the present disclosure cover the modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalents.