PHOTOVOLTAIC MODULE FASTENING SYSTEMS II

Abstract

A PV module alignment or attachment system and method that contains multi-connectors that interact with the modules along rows or columns of an array of the modules. In some versions, the multi-connectors connect to frames of the modules in a row or column and maintain the module-to-module height between modules. The multi-connectors connect to flanges on the frames, which flanges are molded into the frames or bolted to the frames.

Claims

1. A method comprising: supplying PV modules having faces; and installing an array of the modules in an earth mount configuration on an earth surface having a contour, wherein the array comprises a multi-connector and the multi-connector joins at least some modules at adjoining corners.

2. The method of claim 1, wherein the multi-connector maintains a module-to-module edge alignment.

3. The method of claim 2, wherein the multi-connector interacts with a module through a frame.

4. The method of claim 3, wherein the array comprises a row of greater than 25 or 50 modules.

5. The method of claim 4, wherein the array comprises a column of greater than 6, 17, 14, 29, or 50 modules.

6. The method of claim 5, wherein the frame comprises holes.

7. The method of claim 6, wherein the array comprises a leading edge.

8. The method of claim 7, wherein the multi-connector maintains module-to-module edge alignment for face-to-face angles of 0 to 30 degrees.

9. The method of claim 8, wherein the multi-connector connects to flanges on the frame.

10. The method of claim 9, wherein flanges are on the frames of two sides of the module.

11. The method of claim 10, wherein the multi-connector comprises four flexible arms.

12. The method of claim 11, wherein the four flexible arms are composed of two pairs of wire rope connected at a midpoint of each pair.

13. The method of claim 12, wherein the multi-connector further comprises a wire connection that extends to an equipment ground connection or the array.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0024] FIG. 1 is a perspective view of a multi-connector.

[0025] FIG. 2A is a perspective view of a PV module.

[0026] FIG. 2B is a cross-section view of the PV module frame of FIG. 2A.

[0027] FIG. 3A is a perspective view of a PV module.

[0028] FIG. 3B is a perspective view of a PV module.

[0029] FIG. 3C is a perspective view of a PV module.

[0030] FIG. 4A is a perspective view of an array of PV modules with a multi-connector.

[0031] FIG. 4B is a magnified view of part of FIG. 4A.

[0032] FIG. 5A is a perspective view of a PV module.

[0033] FIG. 5B is a magnified view of part of FIG. 5A.

DETAILED DESCRIPTION

[0034] Unless defined otherwise, all technical and scientific terms used in this document have the same meanings as commonly understood by one skilled in the art to which the disclosed invention pertains. Singular forms—a, an, and the—include plural referents unless the context indicates otherwise. Thus, reference to “fluid” refers to one or more fluids, such as two or more fluids, three or more fluids, etc. When an aspect is to include a list of components, the list is representative. If the component choice is limited explicitly to the list, the disclosure will say so. Listing components acknowledges that exemplars exist for each component and any combination of the components—including combinations that specifically exclude any one or any combination of the listed components. For example, “component A is chosen from A, B, or C” discloses exemplars with A, B, C, AB, AC, BC, and ABC. It also discloses (AB but not C), (AC but not B), and (BC but not A) as exemplars, for example. Combinations that one of ordinary skill in the art knows to be incompatible with each other or with the components' function in the invention are excluded, in some exemplars.

[0035] When an element or layer is called being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected, or coupled to the other element or layer, or intervening elements or layers may be present. When an element is called being “directly on”, “directly engaged to”, “directly connected to”, or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between”, “adjacent” versus “directly adjacent”, etc.).

[0036] Although the terms first, second, third, etc., may describe various elements, components, regions, layers, or sections, these elements, components, regions, layers, or sections should not be limited by these terms. These terms may distinguish only one element, component, region, layer, or section from another region, layer, or section. Terms such as “first”, “second”, and other numerical terms do not imply a sequence or order unless indicated by the context. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from this disclosure.

[0037] Spatially relative terms, such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” may be used for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation besides the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors interpreted.

[0038] The description of the exemplars has been provided for illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular exemplar are not limited to that exemplar but, where applicable, are interchangeable and can be used in a selected exemplar, even if not explicitly shown or described. The same may also be varied. Such variations are not a departure from the invention, and all such modifications are included within the invention's scope.

TECHNOLOGY

[0039] The disclosed technology provides a technique for generating electricity using commercially available utility-scale PV (e.g., CSi, CdTe, CIGS, CIS) modules, new and novel adaptations of these modules, or new module technologies. A group of modules is mounted in direct contact and parallel with the Earth's surface. This mounting establishes an earth orientation of the PV modules, as distinguished from a solar orientation. But contouring of the soil and other mounting considerations will account for the sun's angle.

[0040] The modules are tiled into a grid pattern edge to edge and end to end. This technology does not limit how the modules attach to one another or the Earth. This arrangement of modules substantially reduces the wind loading effects of the modules. The electrical arrangement of the modules allows for both series and parallel connections and eliminates, but does not preclude, the need for discrete wiring harnesses and harness supporting means used by traditional utility-scale solar plant PV power plant systems. This module arrangement provides significant advantages when used with string or microinverters but is equally suitable for industry-standard central inverters or alternate power conversion and transmission technologies.

[0041] Modules using prior art conductive module-support structures require module bonding and grounding to meet code.

[0042] This module arrangement dispenses with steel and steel structures in the power plant and their corrosion while increasing power plant life sometimes to greater than 40 years. But steel, coated or otherwise, may be used with these systems.

[0043] The arrangement of modules allows for both commercially available and new techniques for module cleaning and dust removal, increasing the effective energy production rate.

[0044] The module arrangement reduces high wind (sometimes hurricane strength) forces on the modules, which increases the cost of or often precludes construction of solar power plants in high-wind regions. Since high winds easily damage the modules, removing them from high winds reduces repair and replacement costs.

[0045] This technology allows for module cooling methods such as evaporative cooling, applying high emissivity coatings, adding “air vents” on module edges, adding heat transfer materials, or using heat transfer methods, increasing the modules' energy production rates. In addition, ground positioning avoids module heating from indirect sunlight and sunlight-heated ground. This positioning transforms the ground from a heat source to a heat sink.

[0046] The disclosed technology increases the power density per acre of land. As a result, the quantity of acres used per power production unit is reduced by over 50% from traditional utility-scale solar plant PV power plants. In addition, this technology eliminates row to row spacing as required to prevent shading of rows of modules.

[0047] Since the disclosed technology allows the PV array to follow existing land contours, the typical need for mass grading, plowing, tilling, cutting, and filling within arrays can be reduced or eliminated.

[0048] While not tracking the sun reduces module performance, the overall cost savings from reduced electrical losses in wiring, removal of the structural steel racking system, energy increases from increased module cleaning, reduced material cost, and reduced construction schedule and risk costs yields a reduced produced energy price (LCOE) of greater than 10% over current technologies.

[0049] This adjacent positioning allows wiring connections or harnesses to take advantage of the adjacent relationships across two or more rows, reducing the need for harness connections. Module to module string connection distances are reduced in a particular arrangement because adjacent rows can be connected without “skip stringing” or “leapfrog wiring”. DC Homerun connections, commonly called “whips,” are reduced due to eliminating row-to-row spacing requirements. In an alternate arrangement, sequential connections can be made with “next” panels in adjacent rows, reducing the length of connections required for “skip stringing” or “leapfrog wiring”.

[0050] Eliminating structural racking affords an additional advantage with wire harnessing. Since there are no racks, there is no need to consider racks and associated wire management when designing wire harnesses. Thus, module strings can terminate at both ends of the strings close to the inverters. Multiple strings closely terminating allows inverter positioning close to string end terminations.

[0051] Multi-Connectors

[0052] The multi-connector system is a flexible module retaining and mounting system used in Earth-mounted solar PV utility-scale installations. The multi-connector mechanically and structurally retains PV modules of an array and electrically bonds or grounds module frames to each other. This interconnection is between one to four adjacent modules. The interconnection is flexible, which facilitates more significant module-to-module grade changes. Thus, the array will not be damaged by mounting on soils that have a marked change in nature over the array, such as changing between expansive and contractive soils. In addition, the electrical connectivity creates a redundant ground or bond between adjacent modules that extend module-wise across the entire array.

[0053] In some exemplars, the multi-connector system facilitates incorporating more modules into arrays or islands than some systems using perimeter blocks, which decreases the costs of the perimeter blocks.

[0054] The multi-connector system flanges provide pivot points to better tolerate module to module grade changes without increasing the gap between module frames caused by more significant grade changes.

[0055] The multi-connector component inhibits module overlap while remaining flexible for grade changes. In addition, this system or racking method creates automatic lateral spacing between adjacent solar modules.

TABLE-US-00001 multi-connector 100 flexible arm 200 electrical connector 300 ferrule 400 tap 410 bonding hole 450 flange-short 500 flange-long 600 module 12 frame 13 bolt 14 equipment grounding conductor 15 wire connection 16 perimeter block 50 frame profile 700 weep hole 114

[0056] FIG. 1 depicts multi-connector 100. Multi-connector 100 has, in this exemplar, four flexible arms 200 extending from ferrule 400. Electrical connectors 300 terminate each arm 200.

[0057] FIG. 2A depicts a portion of the PV module 12 having frames 13. This version shows frame 13 with weep hole 114 and flange-long 600. Bonding hole 450 pierces flange-long 600. FIG. 2B depicts a profile of the extrusion that forms frame 13. In this exemplar, frame 13 has flange-long 600.

[0058] FIG. 3A depicts a perspective view of a corner of module 12 showing the electrical connectors 300 of a single flexible arm 200 of the multi-connector 100 attached to frame 13 of module 12 using bolt 14. In this figure, bolt 14 threads into bonding hole 450. The figure shows module 12 with flange-long 600. FIG. 3B depicts four of module 12 arranged as the modules would be arranged in an array 20 of modules. Array 20 contains modules 12 nominally mounted flat on the ground, such as in an Earth Mount system. Four modules 12 meet at the corners of each module 12 with a flexible arm 200 connected to each module 12. This arrangement creates a connection among all four modules 12.

[0059] FIG. 3C depicts an arrangement of modules like that of FIG. 3B except that FIG. 3C depicts flange-short 500 instead of flange-long 600.

[0060] FIG. 4A depicts an edge of array 20 abutting perimeter block 50. In this arrangement, two flexible arms 200 connect to flange-long 600, and two flexible arms 200 connect to perimeter block(s) 50. Equipment grounding conductor 15 runs along the perimeter of array 20 along perimeter block(s) 50.

[0061] FIG. 4B is an expanded view of the collection of FIG. 4 A. It shows wire connection 16 connecting between multi-connector 100 and equipment grounding conductor 15. In this exemplar, wire connection 16 and equipment grounding conductor 15 are joined with tap 410.

[0062] FIG. 5A shows module 12 having a bolted-on version of flange-long 600. Flange-long 600 connects to frame 13 with bolts, screws, or other connectors. FIG. 5B shows module 12 having a bolted-on version of flange-short 500. Flange-short 500 connects to frame 13 with bolts, screws, or other connectors.

[0063] In operation, the multi-connector creates a mechanical connection and electrical bond between adjacent modules in an array of modules.

[0064] The multi-connector component captures all four corners of adjacent modules, retaining them within horizontal and vertical height tolerance requirements for mounting and wind loading.

[0065] The multi-connector system can be installed on existing module frame technology using a bolt-on flange to module frame or be employed by using a new Erthos designed extruded module frame.

[0066] The multi-connector flange is threaded to meet NEC grounding requirements for the number of threads per inch of metallic contact.