Building integrated photovoltaic (BIPV) systems provide for solar panel arrays that can be aesthetically pleasing to an observer. BIPV systems can be incorporated as part of roof surfaces as built into the structure of the roof, particularly as multi-region roofing modules that have photovoltaic elements embedded or incorporated into the body of the module, in distinct tiles-sized regions. Such multi-region photovoltaic modules can replicate the look of individual roofing tiles or shingles. Further, multi-region photovoltaic modules can include hinged support structures along the upper edge of the modules, allowing for lifting of portions of an installed module, giving access to the underlying roof deck for more efficient installation, maintenance, or removal of roofing structures down-roof of the installed module.
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This application is a divisional of application Ser. No. 15/712,113, filed on Sep. 21, 2017, which is incorporated by reference herein.
This generally relates to photovoltaic arrays.
Solar is becoming increasingly popular in the United States and abroad, but penetration remains relatively low versus the number of homes that could benefit from solar. The price per kilowatt for solar is now competitive with or below that of fossil fuel-based utility power in most areas, however, solar largely remains a niche product for those who value saving money, reducing CO2 emissions, or both.
One factor that may limit the adoption of solar technology is aesthetics. Most residential solar systems are installed as modules over an existing tile or composition shingle roof. The solar array, which often only covers a portion of the roof, or even a portion of one mounting plane of the roof, stands out as separate and distinct from the existing roof, both in height and material. This difference is therefore visible from the street level and even over large distances.
Further, the time and complexity of a solar array installation can be an obstacle to the adoption of solar technology. Many improvements have been made to streamline and improve the process of installing, mounting, and connecting individual solar panels, but there remains an opportunity for innovating and even better refining the systems and methods of installing different types of photovoltaic arrays.
Another obstacle to solar adoption in existing homes is the dissonance between the age of the existing roof and the solar system, particularly where the existing roof is made from composition shingles. The expected life of a modern-day solar system is 25 years or more, and the expected life of a composition shingle roof is also about 25-35 years, depending on the local climate and specific materials. At the time a customer is considering going solar, their existing roof may be several years, if not decades, into that lifespan. So the customer may be presented with the dilemma of getting a new roof first, increasing the cost of going solar, or installing a 25-year solar system on a roof which may have a relatively shorter remaining operational lifespan.
Accordingly, there is a need to resolve the dissonance between the expected life of the solar system and the remaining life of the roof that also blends in more aesthetically with the complete roof surface or at least the mounting plane, and that does not require the prospective customer to pay for a new roof and a new solar system over that roof.
Various embodiments provide a new and improved approach to installing solar on new roofs and existing roofs, and in particular, presenting a roof that appears to be a tile roof. Some aspects fit over an existing tile roof and/or other suitable roof surfaces (e.g., a metal roof, composite shingle, roof deck, underlayment or insulation layer). In particular, aspects of the disclosure are modular and flexible, which simplifies installation as well as replacement of individual photovoltaic modules of the system. In addition, some aspects cost less to make and install compared to conventional solar systems. Further, some arrangements of photovoltaic portions (and/or non-photovoltaic portions) of modules can generate a visual pattern and aesthetic that appears consistent with traditional roofing materials. Moreover, with a hinged structure to facilitate installation and assembly of photovoltaic modules, great advantages can be had in reducing the number of (or even eliminating) battens beneath the photovoltaic modules forming a solar array. Indeed, with a hinged structure, photovoltaic modules can be efficiently installed in a down-roof direction. Some solar systems can be installed as a new roof rather than a re-roof or mounted to an existing roof. These and other embodiments are discussed in greater detail in the detailed description and drawing figures.
In some embodiments, the present disclosure is directed toward a hinged multi-section solar or photovoltaic module having a plurality of photovoltaic elements including: two or more photovoltaic tiles, each photovoltaic tile having at least one solar cell; and a support skeleton. In some aspects, the support skeleton is formed having: a spine structure defining a longitudinal axis; a plurality of midsection supports, extending from the spine, configured to extend under gaps between the two or more photovoltaic glass tiles; and one or more flexure hinges extending from the spine, each flexure hinge having a hinge foot configured to secure to a roof deck and a hinge leg configured to bond to one of the photovoltaic glass tiles. In various aspects, the support skeleton can be made of a polymer, where the polymer can be polyphenyl ether (PPE), polystyrene (PS), poly(methyl methacrylate) (PMMA), an acetyl, a polycarbonate, or a combination thereof. In other aspects, each section of the support skeleton can be about two millimeters (2 mm) thick, where for example, each of the hinge foot, the spine, the hinge leg, or the midsection supports as individually measured can be about two millimeters (2 mm) thick. In further aspects, each photovoltaic glass tile can be bonded to two flexure hinges. In some aspects, the spine further includes an inline-brace positioned between adjacent photovoltaic tiles.
In some embodiments the hinge leg and hinge foot of the flexure hinge are connected by a bridge structure. In other aspects, the hinge leg can further have stiffening ribs that extend along of the length of the hinge leg, where in some such aspects, the stiffening ribs can be from about 25% to about 95% of the length of the hinge leg. In further aspects, the hinge leg can be from about 25% to about 100% of the length of the hinge foot. In another aspect, the hinge foot can be about twice, about three times, about four times, or about equal to the length of the hinge leg. In some aspects, the flexure hinge can a range of motion allowing for bending up to a 10°, 20°, 45°, or 90° angle from a flat configuration (or relative to the plane of a roof deck).
In other embodiments, the present disclosure is directed toward course of a building integrated photovoltaic array, including: a plurality of photovoltaic modules, arranged in a horizontal row on a roof deck, wherein the photovoltaic modules are attached through a plurality of flexure hinges to the roof deck; and an electrical box, electrically connected to the plurality of photovoltaic modules. In such aspects, each photovoltaic module can further include: three photovoltaic tiles, each photovoltaic tile having at least one solar cell, each of the photovoltaic tiles being electrically connected to each other; a support skeleton having a spine, wherein the three photovoltaic tiles are arranged linearly along the support skeleton, with the support skeleton coupled to the underside of the upper edges of the three photovoltaic tiles; a plurality of midsection supports, extending from the spine, configured to extend under two gaps between the three linearly arranged photovoltaic tiles; and three pairs of flexure hinges extending from the spine, where each of the three photovoltaic tiles has one of the pairs of flexure hinged adhered to the underside of the respective photovoltaic tile. In some aspects, each flexure hinge can have hinge foot and a hinge leg, where the hinge foot is directly secured to the roof deck, such as with screws. In other aspects, each photovoltaic tile further comprises a sealant material on the underside of the photovoltaic tile, arranged to be in between the midsection supports. In other aspects, the photovoltaic tiles can be held in cantilever by the flexure hinges over a relatively down-roof region of roof deck. In further aspects, the support skeleton can have a tail end flange that is configured to partially support to a horizontally adjacent member of the plurality of photovoltaic modules.
In further embodiments, the present disclosure is directed toward a method of installing a building integrated photovoltaic array, including the steps of: installing framing structures on a roof deck; positioning and securing a first course of solar roofing modules proximate to a ridge of the roof; positioning and securing successive subsequent courses of solar roofing modules, progressively down-roof along the roof deck, according to a slope of the roof deck; positioning and securing a bottom-most course of solar roofing modules proximate to an eave of the roof; and electrically connecting each course of said PV modules to a local power grid. In some aspects, the method can include the steps of lifting the photovoltaic tiles of an up-roof solar roofing module within the range of motion of a plurality of flexure hinges coupled to the photovoltaic tiles; placing and installing the subsequent solar roofing module to the roof deck in a position down-roof of the up-roof solar roofing module; and lowering the photovoltaic tiles of the up-roof solar roofing module into place, such that each of flexure hinges are in a coupled configuration. In other aspects, the method can include the step of placing the progressively down-roof course of solar roofing modules at a variable position along the slope of the roof deck, such that the down-roof course of solar roofing modules has a specifically adjusted reveal area.
Illustrative aspects of the present disclosure are described in detail below with reference to the following drawing figures. It is intended that that embodiments and figures disclosed herein are to be considered illustrative rather than restrictive
FIG. 1A shows an example of a prior art photovoltaic array installed on a roof.
FIG. 1B shows an exemplary prior art photovoltaic module.
FIG. 2A shows a schematic top perspective view of an exemplary hinged multi-section photovoltaic module, in accordance with aspects of the disclosure.
FIG. 2B shows a schematic exploded view of the hinged multi-section photovoltaic module as shown in FIG. 2A, in accordance with aspects of the disclosure.
FIG. 2C shows a schematic bottom perspective view of the hinged multi-section photovoltaic module as shown in FIG. 2A, in accordance with aspects of the disclosure.
FIG. 3A shows a top surface plan of an exemplary hinged multi-section photovoltaic module, having three PV tiles, in accordance with aspects of the disclosure.
FIG. 3B shows a bottom surface plan view of the hinged multi-section photovoltaic module, as shown in FIG. 3A, in accordance with aspects of the disclosure.
FIG. 4A shows a schematic of an exemplary building integrated photovoltaic system having hinged multi-section PV modules, illustrated without PV tiles, in accordance with aspects of the disclosure.
FIG. 4B shows a schematic of an exemplary building integrated photovoltaic system having hinged multi-section PV modules, in accordance with aspects of the disclosure.
FIG. 5 illustrates a foot and leg of a hinged multi-section photovoltaic module, in accordance with aspects of the disclosure.
FIG. 6A illustrates a hinged multi-section photovoltaic module with the hinge in an open configuration, in accordance with aspects of the disclosure.
FIG. 6B illustrates a hinged multi-section photovoltaic module with the hinge in an coupled configuration, in accordance with aspects of the disclosure.
FIG. 7 shows a cross-sectional illustration of hinged multi-section photovoltaic modules mounted to a roof surface, in accordance with aspects of the disclosure.
FIG. 8 is a flowchart illustrating an exemplary process of assembling and installing a building integrated photovoltaic system, in accordance with aspects of the disclosure.
The present disclosure describes various embodiments of photovoltaic roofing systems and associated systems and methods, and in particular building integrated photovoltaic roofing systems. Some embodiments relate to building integrated photovoltaic module assemblies and associated systems and methods. In various embodiments, the systems described herein lower costs of conventional systems in which a photovoltaic (“PV”) system is installed over a roof, and at the same time can provide an improved aesthetic for a PV roof system, and particularly for a building integrated photovoltaic (“BIPV”) system.
Certain details are set forth in the following description and in the Figures to provide a thorough understanding of various embodiments of the present technology. Other details describing well-known structures and systems often associated with PV systems, roofs, etc., however, are not set forth below to avoid unnecessarily obscuring the description of the various embodiments of the present technology.
There is a constant need to improve upon the speed and efficiency of the installation process of PV systems, the visual aesthetic of an installed PV array, as well as the resilience and operational lifetime of PV systems and arrays. Innovations as considered by the present disclosure employ a hinged multi-section PV module, generally spanning a width equal to three PV tiles (or shingles), that provides for a structural component that reduces installation time, is visually appealing, and includes non-rigid features that can improve upon the functional lifespan of each PV module. In particular, the range of motion of the hinge, considered alternatively or in combination with, the flexibility of the multi-section PV modules disclosed herein allows for an ease of installation due to the slack and ability to adjust the edges of the PV modules, and the ability to wedge in hinge structures underneath adjacent up-roof courses of PV modules, as they are being arranged as part of an array. This improves upon the installation and assembly process which generally takes less time than assembly of a traditional, rigid PV structure. Further, the hinged multi-section PV module having a form factor equivalent to having three PV tiles built into the module, but distinct from each other and spaced to appear as if they are physically separate, improves the installation time (installing “three PV tiles” at once as opposed to only one at a time) and reduces connector counts over individual roof tiles, while concurrently presenting a visually pleasing roof structure to an average observer. The flexibility of the hinged multi-section PV modules can result in a structure that can better withstand environmental strains (e.g., wind shear, uplift, thermal expansion & contraction, etc.) and uneven roof surfaces due to the range of tilting freedom provided between paired solar cells or PV tiles of the multi-section PV module. Particularly, the hinged multi-section PV modules of the present disclosure have a spine-like support structure on which hinge-like structures are positioned, providing a degree of between the support structure and the PV tiles coupled to the support structure, allowing the support structure to be secured to a roof deck before positioning the PV tiles into an installed configuration. Further details of these advantages are discussed below.
Many of the details, dimensions, angles and other features shown in the Figures are merely illustrative of particular embodiments. Accordingly, other embodiments can include other details, dimensions, angles and features without departing from the spirit or scope of the present disclosure. Various embodiments of the present technology can also include structures other than those shown in the Figures and are expressly not limited to the structures shown in the Figures. Moreover, the various elements and features shown in the Figures may not be drawn to scale. In the Figures, identical reference numbers identify identical, or at least generally similar, elements.
As used herein, the term “substantially” refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, an object that is “substantially” uniform in height to another object would mean that the objects are either completely or nearly completely uniform in height. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context, however, generally speaking, the nearness of completion will be so as to have the same overall result as if absolute and total completion were obtained.
As used herein, the term “about” is used to provide flexibility to a numerical range endpoint by providing that a given value may be “above” or “below” the value. For example, the given value modified by about may be ±10% relative to the given value.
Wherever used throughout the disclosure and claims, the term “generally” has the meaning of “approximately” or “closely” or “within the vicinity or range of”. The term “generally” as used herein is not intended as a vague or imprecise expansion on the term it is selected to modify, but rather as a clarification and potential stop gap directed at those who wish to otherwise practice the appended claims, but seek to avoid them by insignificant, or immaterial or small variations. All such insignificant, or immaterial or small variations should be covered as part of the appended claims by use of the term “generally”.
As used herein, the term “building integrated photovoltaic system” or “BIPV” generally refers to photovoltaic systems integrated with building materials to form at least a portion of a building envelope. For example, the BIPV system can form the roof or roofing membrane of a building. The BIPV systems described herein can be retrofitted, can be a part of a new construction roof, or a combination of both. Such building integrated photovoltaic structures can be alternatively referred to as building integrable photovoltaic (“BIP”) or building applied photovoltaics (“BAPV”). Components of a BIPV system used, in part, as part of the actual building envelope (e.g., roofing membrane), can provide a watertight or substantially watertight seal for the roof surface.
For the sake of distinguishing between structural elements of the present BIPV system, as used herein, the term “solar cell” refers to the structures of the system with solar energy collecting elements (often silicon elements), the term “PV roof tile” refers to such solar collecting elements as mounted or adhered to a single structural roof tile, and the term “PV module” refers to a set of solar cells, PV regions of a PV module, and/or other PV units that are mechanically and electrically connected to each other as part of a single structural unit. In the context of a PV module, the term “PV section” refers to sections of the PV modules that can each appear similar to a PV roof tile, and are configured to support solar cells similarly to a single PV roof tile.
As used herein, the terms “up-roof” and “down-roof” are used to provide orientation, direction, position, or a reference point relative to or in context of a roof or roofing surface upon which the systems described herein are installed on and/or from a portion of. Up-roof generally refers to an orientation or portion that is relatively closer to the roof ridge while down-roof refers to an orientation or portion that is relatively closer to the roof eave.
As used herein, the term “reveal” refers to the portion of a PV tile or PV module that is exposed sunlight and/or holds or mounts solar energy collecting elements, such as silicon-based solar cells. As used herein, conversely, the term “lapped” or “overlap” region refers to the section of a PV tile or PV module along its upper (up-roof) edge that, as part of a roofing installation, will be physically covered or underneath bottom surfaces (i.e. not exposed to sunlight) of the next adjacent, up-roof course of PV tiles, PV modules, or other roofing components.
As used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.