Photovoltaic roof tile feet

Abstract

Foot configurations for photovoltaic (PV) roof tiles are described. The feet include a plurality of retention mechanisms that are engaged by hooks or brackets on adjacent roof tiles to prevent upward movement of the roof tile positioned on the roof from the foot. The feet also position the PV roof tile a fixed distance above the roof substrate without the need to add a set of battens above the roof substrate. Non-PV roof tiles that fit the described feet are also described. The non-PV roof tiles are configured so that they can be cut into smaller pieces as needed to fill small openings in the roof top surface.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. Provisional Patent Application No. 63 / 426,566, entitled "PHOTOVOLTAIC ROOFING TILE FOOT," filed November 18, 2022, the contents of which are incorporated herein by reference in their entirety.

[0002] The present disclosure relates generally to photovoltaic (PV) roof tiles. More specifically, the present disclosure describes a PV roof tile foot having a connection interface configured to be coupled to a PV roof tile and a non-PV roof tile on a roof top side. [Background technology]

[0003] In residential and commercial solar energy installations, the roofs of buildings are typically equipped with PV modules, also called PV panels or solar panels, which may include a two-dimensional array (e.g., 6x12) of solar cells. PV roof tiles (or solar roof tiles) can be a specific type of PV module that provides weather resistance and an attractive aesthetic appearance for the residence while also functioning as a PV module for converting solar energy into electricity. PV roof tiles can be shaped similarly to conventional roof tiles and can include one or more solar cells encapsulated between front and back covers, but typically enclose fewer solar cells than conventional solar panels.

[0004] The front and back covers can be tempered glass or other materials that can protect the PV cells from weather elements. A typical roof tile is 15 inches x 8 inches = 120 square inches = 774 cm 2 and a typical solar cell may have dimensions of 6 inches by 6 inches = 36 square inches = 232 cm 2It should be noted that the dimensions of the roof tile may be different from those of the PV roof tile. Typically, a PV roof tile installation will include a mix of PV and non-PV roof tiles, since incorporating PV structures into every roof tile would typically provide more energy than is required to power a typical home. For this reason, a roofing element that can be used with both PV and non-PV roof tile modules would be desirable and could improve the affordability of PV roof configurations. Summary of the Invention [Problem to be solved by the invention]

[0005] One embodiment may provide a PV roof tile having feet configured to hold the leading edge of the roof tile in place on the roof of the PV roof tile. [Means for solving the problem]

[0006] An individual PV roof tile is disclosed, the individual PV roof tile including: a protective cover; a photovoltaic (PV) tile backer; a plurality of solar cells disposed between the protective cover and the PV tile backer, the plurality of solar cells having a first electrical terminal proximate a first end of the PV roof tile and a second electrical terminal proximate a second end of the PV roof tile; and a plurality of feet, each foot comprising: a standoff disposed at a first end of the foot and coupled to a downwardly facing surface of the PV tile backer; and a coupling assembly disposed at a second end of the foot opposite the first end of the foot, the coupling assembly defining a plurality of adjacent retention features configured to receive and prevent upward movement of one or more portions of the roof tile adjacent the PV roof tile.

[0007] A roof is disclosed that includes a plurality of roof tiles, the roof including: a first roof tile bonded directly to a roof substrate, the first roof tile comprising: a first protective cover, a first PV tile backer, a first plurality of solar cells disposed between the first protective cover and the first PV tile backer, and a plurality of feet, each foot disposed between the PV tile backer and the roof substrate and comprising a coupling assembly protruding laterally from below the PV tile backer; and a second roof tile disposed on the roof from the first roof tile, the second roof tile comprising: a second protective cover, the second PV tile backer, a second plurality of solar cells disposed between the second protective cover and the second PV tile backer, and a tile hook bonded to a downwardly facing surface of the PV tile backer, the second roof tile comprising a hook portion that engages within a retention mechanism of a coupling assembly of a first foot of the plurality of feet.

[0008] A "solar cell strip," "PV strip," "small cell," or "strip" is a portion or segment of a PV structure, such as a solar cell. The PV structure may be divided into several strips. The strips may have any shape and any size. The width and length of the strips may be the same or different from each other. The strips may be formed by further dividing a previously divided strip.

[0009] "Finger line," "finger electrode," and "finger" refer to an elongated, conductive (eg, metal) electrode of a PV structure for collecting carriers.

[0010] A "bus bar," "bus line," or "bus electrode" refers to an elongated, conductive (e.g., metal) electrode of a PV structure for aggregating the current collected by two or more finger lines. A bus bar is typically wider than a finger line and can be deposited or otherwise positioned anywhere on or within the PV structure. A single PV structure can have one or more bus bars.

[0011] "PV structure" may refer to a solar cell, a segment, or a solar cell strip. A PV structure is not limited to a device manufactured by a particular method. For example, a PV structure may be a crystalline silicon-based solar cell, a thin film solar cell, an amorphous silicon-based solar cell, a polycrystalline silicon-based solar cell, or a strip thereof. [Brief explanation of the drawings]

[0012] [Figure 1] 1 illustrates an exemplary configuration of PV roof tiles on a house.

[0013] [Figure 2] 1 illustrates a perspective front view of an exemplary PV roof tile, according to one embodiment.

[0014] [Figure 3A] 1 illustrates an exemplary configuration of a multi-tile module, according to one embodiment.

[0015] [Figure 3B] 1 illustrates a cross section of an exemplary multi-tile module, according to one embodiment.

[0016] [Figure 4A] 1 illustrates a series connection between three adjacent cascaded PV strips according to one embodiment.

[0017] [Figure 4B] FIG. 1 illustrates a side view of a string of cascaded strips according to one embodiment.

[0018] [Figure 4C] 1 illustrates an exemplary solar roof tile, according to one embodiment.

[0019] [Figure 5A] 1 illustrates a top view of an exemplary multi-tile module, according to one embodiment.

[0020] [Figure 5B] 1 illustrates a top view of another exemplary solar roof tile, according to one embodiment.

[0021] [Figure 6] FIG. 1 shows a partial view of a roof with several solar and passive roof tiles.

[0022] [Figure 7A] 1 shows a plan view of the roof substrate-facing surface of a PV roof tile.

[0023] [Figure 7B] A close-up of the foot of a PV roof tile is shown. [Figure 7C] A close-up of the foot of a PV roof tile is shown.

[0024] [Figure 7D] Different views of the PV Luke are shown. [Figure 7E] Different views of the PV Luke are shown.

[0025] [Figure 7F] 1 shows a plan view of a number of PV roof tiles joined together.

[0026] [Figure 7G] 10 shows how the hook portion of the tile hook slides into the retention mechanism of the PV roof tile foot joining assembly. [Figure 7H] 10 shows how the hook portion of the tile hook slides into the retention mechanism of the PV roof tile foot joining assembly.

[0027] [Figure 8A] FIG. 1 shows a plan view of the downward-facing surface of a non-PV roof tile.

[0028] [Figure 8B] FIG. 1 shows a side view of a PV roof tile mounted on a roof substrate.

[0029] [Figure 8C] 8B shows how the rear bracket of a non-PV roof tile under the roof engages the front bracket segment of the non-PV roof tile shown in FIG. 8B.

[0030] [Figure 8D] 1 shows a perspective view of the top surface of a non-PV roof tile, along with a close-up view of the water channels in the non-PV roof tile.

[0031] [Figure 9A] 10A-10C show various views of a joining assembly of a foot of a PV roof tile joined to a front bucket segment of a non-PV roof tile. [Figure 9B] 10A-10C show various views of a joining assembly of a foot of a PV roof tile joined to a front bucket segment of a non-PV roof tile. [Figure 9C] 10A-10C show various views of a joining assembly of a foot of a PV roof tile joined to a front bucket segment of a non-PV roof tile.

[0032] [Figure 10A] Different combinations of PV and non-PV roof tiles are shown. [Figure 10B] Different combinations of PV and non-PV roof tiles are shown.

[0033] [Figure 11] 10B illustrates the configuration shown in FIG. 10A with the addition of a flashing component. DETAILED DESCRIPTION OF THE INVENTION

[0034] The following description is presented to enable any person skilled in the art to make and use the embodiments and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Thus, the disclosed system is not limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features disclosed herein. overview

[0035] Embodiments of the present invention solve at least the technical problem of reducing the number of components required to join PV roof tiles and non-PV roof tiles together. In particular, the present disclosure describes a foot for a PV module that can be attached to and secured to other PV roof tiles and non-PV roof tiles. In particular, the foot defines a first opening for receiving a tile hook of another PV module and two other openings located on opposite sides of the first opening for engaging adjacent front brackets of non-PV roof tiles. In this way, a single type of foot can be used interchangeably to secure both PV roof tiles and non-PV roof tiles together.

[0036] In addition to describing novel PV roof tile feet, several advances are described with respect to forming robust, flexible non-PV roof tiles. In particular, roof tiles can be formed from sheet metal and finished to have the appearance of a PV roof tile. Forming roof tiles from sheet metal material results in non-PV roof tiles that can be efficiently cut to fit portions of a roof surface that would otherwise be unable to accommodate a rectangular roof tile. For example, stock rectangular non-PV roof tiles can be cut into nearly any polygonal shape. Several triangular tiles may be needed near various ridges and / or valleys on a particular roof surface. By making one or two cuts in the non-PV roof tile, triangles of trapezoidal pieces can be formed. The combination of a multi-purpose foot formed from metal with a non-PV roof tile can substantially reduce the number of parts required to perform a PV roof installation.

[0037] A "solar cell" or "cell" is a PV structure capable of converting light into electricity. Cells can have any size and shape and can be made from a variety of materials. For example, a solar cell can be a PV structure fabricated on a silicon wafer, or one or more thin films on a substrate material (e.g., glass, plastic, or any other material capable of supporting a PV structure), or a combination thereof.

[0038] A "solar cell strip," "PV strip," "small cell," or "strip" is a portion or segment of a PV structure, such as a solar cell. The PV structure may be divided into several strips. The strips may have any shape and any size. The width and length of the strips may be the same or different from each other. The strips may be formed by further dividing a previously divided strip.

[0039] "Finger line," "finger electrode," and "finger" refer to an elongated, conductive (eg, metal) electrode of a PV structure for collecting carriers.

[0040] A "bus bar," "bus line," or "bus electrode" refers to an elongated, conductive (e.g., metal) electrode of a PV structure for aggregating the current collected by two or more finger lines. A bus bar is typically wider than a finger line and can be deposited or otherwise positioned anywhere on or within the PV structure. A single PV structure can have one or more bus bars.

[0041] "PV structure" may refer to a solar cell, a segment, or a solar cell strip. A PV structure is not limited to a device manufactured by a particular method. For example, a PV structure may be a crystalline silicon-based solar cell, a thin film solar cell, an amorphous silicon-based solar cell, a polycrystalline silicon-based solar cell, or a strip thereof. PV roof tiles and multi-tile modules

[0042] A PV roof tile (or solar roof tile) is a type of PV module that is shaped like a roof tile and typically encapsulates fewer solar cells than a conventional solar panel. It is noted that such a PV roof tile can function simultaneously as both a PV cell and a roof tile. In some embodiments, the systems disclosed herein may be applied to PV roof tiles and / or other types of PV modules.

[0043] 1 shows an exemplary configuration of PV roof tiles on a house. PV roof tiles 100 can be installed on a house similar to conventional roof tiles or shingles. In particular, PV roof tiles can be arranged with other tiles in a manner that prevents water from entering the building.

[0044] A PV roof tile can encapsulate multiple solar cells or PV structures, and individual PV structures can include one or more electrodes, such as bus bars and finger lines. The PV structures within a PV roof tile can be electrically and optionally mechanically coupled to one another. For example, multiple PV structures can be electrically coupled to one another via their respective bus bars and metal tabs to create a series or parallel connection. Furthermore, electrical connections can be made between two adjacent tiles so that several PV roof tiles can jointly power one another. The exterior features of a PV roof tile can allow the PV roof tile to blend in and appear identical to a non-PV roof tile. In some embodiments, the exterior features can be designed to behave ideally when viewed from angle 102.

[0045] FIG. 2 shows a perspective view of an exemplary PV roof tile, according to one embodiment. Solar cells 204 and 206 can be hermetically sealed between a top glass cover 202 and a PV tile backer 208, which together can protect the solar cells from various weather elements. In the example shown in FIG. 2 , a metal tab strip 212 can contact the front electrode of solar cell 204 and extend beyond the left edge of glass 202, thereby serving as the PV roof tile's first polarity contact electrode. Tab strip 212 can also contact the back surface of solar cell 206, forming a series connection between solar cell 204 and solar cell 206. On the other hand, tab strip 214 can contact the front electrode of solar cell 206 and extend beyond the right edge of glass cover 202, serving as the PV roof tile's second polarity contact electrode. In some embodiments, PV tile backer 208 can be a standard PV tile backer formed from one or more layers of polymer, such as a fluoropolymer or a combination of PET and EVA layers. Alternatively, the PV tile backer 208 can take the form of a rear glass cover.

[0046] In some embodiments, the array of solar cells 204 and 206 may be encapsulated between a top glass cover 202 and a back cover 208. A top encapsulant layer, which may be polymer-based, may be used to seal the top glass cover 202 to the array of solar cells 204 / 206. Specifically, the top encapsulant layer may include polyvinyl butyral (PVB), thermoplastic polyolefin (TPO), ethylene vinyl acetate (EVA), or N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD). Similarly, a bottom encapsulant layer, which may be of a similar material system, may be used to seal the array of solar cells to the back cover 208. The PV roof tile may also include other optional layers, such as optical filters or coating layers, or layers of nanoparticles to provide a desired color appearance. In the example of FIG. 2, the module or roof tile 300 may also include an optical filter layer between the array of solar cells and the front glass cover 202 .

[0047] To facilitate more scalable production and easier installation, multiple PV roof tiles can be manufactured together, while the tiles are joined in a rigid or semi-rigid manner. FIG. 3A shows an exemplary configuration of a multi-tile module, according to one embodiment. In this example, three PV roof tiles 302, 304, and 306 can be manufactured with semi-rigid bonds 322 and 324 established between adjacent tiles. Pre-fabricating multiple tiles into a rigid or semi-rigid multi-tile module can significantly reduce the complexity of rooftop installation, as the tiles within the module are connected by tab strips. Note that each multi-tile module can include more or fewer tiles than shown in FIG. 3A.

[0048] FIG. 3B shows a cross section of an exemplary multi-tile module, according to one embodiment. In this example, multi-tile module 350 may include PV roof tiles 354, 356, and 358. These tiles may share a common PV tile backer 352 and may have three individual glass covers 355, 357, and 359, respectively. Each tile may encapsulate two solar cells. For example, tile 354 may include solar cells 360 and 362 encapsulated between PV tile backer 352 and glass cover 355. Tab strips may be used to provide electrical connections within each tile and between adjacent tiles. For example, tab strip 366 may couple the front electrode of solar cell 360 to the back electrode of solar cell 362, forming a series connection between these two cells. Similarly, tab strip 368 may couple the front electrode of cell 362 to the back electrode of cell 364, forming a series connection between tiles 354 and 356.

[0049] Gaps 322 and 324 between adjacent PV tiles may be filled with encapsulant to protect the tab strips that interconnect the two adjacent tiles from weather elements. For example, encapsulant 370 fills the gap between tiles 354 and 356 to protect tab strip 368 from weather elements. Additionally, the three glass covers, PV tile backer 352, and encapsulant together form a semi-rigid structure for multi-tile module 350. This semi-rigid structure may facilitate easier installation while providing some flexibility between the tiles.

[0050] In addition to the examples shown in Figures 3A and 3B, PV tiles can include various forms of PV structures. For example, to reduce internal resistance, each square solar cell shown in Figure 3A can be divided into multiple (e.g., three) smaller strips, each with edge bus bars of different polarity on two opposing edges. The edge bus bars allow the strips to be cascaded one after the other to form a series-connected string.

[0051] FIG. 4A shows a series connection between three adjacent cascaded PV strips, according to one embodiment. In FIG. 4A, strips 502, 504, and 506 are stacked such that strip 504 partially overlaps the adjacent strip 506 to its right and overlaps strip 502 to its left. The resulting string of strips forms a cascaded pattern similar to roof shingles. Strips 502 and 504 are electrically coupled in series via an edge bus bar 508 on the top surface of strip 502 and an edge bus bar 510 on the bottom surface of strip 504. Strips 502 and 504 can be positioned such that the bottom edge bus bar 510 is above and directly contacts the top edge bus bar 508. The coupling between strips 504 and 506 can be similar.

[0052] FIG. 4B shows a side view of a string of cascaded strips, according to one embodiment. In the example shown in FIGS. 4A and 4B, the strips may be 6-inch square or pseudo-square segments of solar cells, with each strip measuring approximately 2 inches by 6 inches. To reduce shading, the overlap between adjacent strips should be kept as small as possible. Thus, in the example shown in FIGS. 4A and 4B, a single bus bar (both top and bottom) may be placed at or near the very edge of the strip. The same cascading pattern may extend along multiple strips to form a series-connecting string, and several strings may be coupled in series or parallel.

[0053] FIG. 4C shows an exemplary solar roof tile, according to one embodiment. Solar roof tile 412 includes a top glass cover 414 and solar cells 516 and 518. The bottom cover (e.g., a PV tile backer) of solar roof tile 412 is not visible in FIG. 4C. Solar cells 416 and 418 can be traditional square or pseudo-square solar cells, such as 6-inch solar cells. In some embodiments, solar cells 416 and 418 can each be divided into three separate pieces of similar size. For example, solar cell 416 can include strips 422, 424, and 426. These strips can be arranged so that adjacent strips partially overlap at their edges, similar to what is shown in FIGS. 4A-4B. For ease of illustration, the electrode grid of the strips, including finger lines and edge bus bars, is not shown in FIG. 4C. In addition to the example shown in FIG. 4C, solar roof tiles can include fewer or more cascaded strips, which can be of various shapes and sizes.

[0054] In some embodiments, multiple solar roof tiles, each enclosing a cascaded string, can be assembled to obtain a multi-tile module. Electrical coupling between the inner tiles has been achieved by overlapping corresponding edge bus bars of adjacent strips. However, inter-tile electrical coupling within such a multi-tile module can be challenging. Strain relief connectors and long bus strips have been used to facilitate inter-tile coupling. However, strain relief connectors can be expensive, and arranging the bus strips after laying out the cascaded strings can be cumbersome. To facilitate low-cost, high-throughput manufacturing of solar roof tiles, in some embodiments, metal strips can be pre-laid on the back cover of the solar tile to form embedded circuits that can be similar to metal traces on a printed circuit board (PCB). More specifically, the embedded circuits can be configured to facilitate electrical coupling between multiple solar roof tiles within a multi-tile module.

[0055] Furthermore, in some embodiments, a Si-based bridge electrode can be attached to the cascaded string to facilitate electrical coupling between the embedded circuitry and the edge bus bars located on the front side of the cascaded string. The Si-based bridge electrode can include a metal layer covering its entire back side and, optionally, a back edge bus bar. The Si-based bridge electrode can turn itself into an electrode of the cascaded string by overlapping its edge (e.g., the back edge bus bar) with the front edge bus bar of the cascaded string, converting the front-facing electrode of the cascaded string into an electrode accessible from the back side of the cascaded string.

[0056] 5A shows a top view of an exemplary multi-tile module, according to one embodiment. Multi-tile module 600 may include PV roof tiles 502, 504, and 506 arranged side by side. Each PV roof tile may include six cascaded strips enclosed between a front cover and a back cover, i.e., busbars positioned at opposite edges of a string of cascaded strips have opposite polarities. For example, if the left-most edge busbar of a strip in PV roof tile 502 has a positive polarity, the right-most edge busbar of the strip will have a negative polarity. A series connection may be established between tiles by electrically coupling busbars with opposite polarities, while a parallel connection may be established between tiles by electrically coupling busbars with the same polarity.

[0057] In the example shown in FIG. 5A, the PV roof tiles are arranged so that their sun-facing sides have the same electrical polarity. As a result, edge bus bars of the same polarity are on the same left or right edge. For example, the left-most edge bus bars of all PV roof tiles can have a positive polarity and the right-most edge bus bars of all PV roof tiles can have a negative polarity, or vice versa. In FIG. 6, the left-most edge bus bars of all strips have a positive polarity (indicated by a "+" symbol) and are located on the sun-facing (or front) surface of the strip, while the right-most edge bus bars of all strips have a negative polarity (indicated by a "-" symbol) and are located on the back surface. Depending on the design of the solar cell layer structure, the polarity and position of the edge bus bars can differ from those shown in FIG. 5A.

[0058] Parallel connections between tiles can be formed by electrically coupling all left-most bus bars to each other via metal tabs 510 and all right-most bus bars to each other via metal tabs 512. Metal tabs 510 and 512, also known as connection buses, are typically used to interconnect individual solar cells or strings. The metal tabs can be stamped, cut, or otherwise formed from a conductive material such as copper. Copper is a highly conductive and relatively low-cost connector material. However, other conductive materials such as silver, gold, or aluminum can also be used. In particular, silver or gold can be used as a coating material to prevent oxidation of copper or aluminum. In some embodiments, an alloy heat-treated to have superelastic properties can be used for all or part of the metal tabs. Suitable alloys can include, for example, copper-zinc-aluminum (CuZnAl), copper-aluminum-nickel (CuAINi), or copper-aluminum-beryllium (CuAlBe). Additionally, the metal tab materials disclosed herein can be engineered in whole or in part to modify their mechanical properties. For example, all or a portion of metal tabs 510 and 512 may be forged (e.g., to increase strength), annealed (e.g., to increase ductility), and / or tempered (e.g., to increase surface hardness).

[0059] The bond between the metal tabs and the busbars can be facilitated by specially designed strain relief connectors. In FIG. 5A, strain relief connector 516 can be used to bond busbar 514 and metal tab 510. Such strain relief connectors are required due to the mismatch in thermal expansion coefficients between metals (e.g., Cu) and silicon. As shown in FIG. 5A, metal tabs (e.g., tabs 510 and 512) may cross paths with strain relief connectors of opposite polarity. To prevent electrical shorting of the PV strip, portions of the metal tabs and / or strain relief connectors can be coated with an insulating film or wrapped with a sheet of insulating material.

[0060] In some embodiments, stamped metal tabs and strain relief connectors may be used to form a series connection between tiles instead of connecting tiles in parallel within a tile module, as shown in FIG. 5A. FIG. 5B shows a top view of an exemplary multi-tile module, according to one embodiment. Tile module 540 may include solar roof tiles 542, 544, and 546. Each tile may include several (e.g., six) cascaded photovoltaic strips arranged in the manner shown in FIGS. 4A and 4B. Additionally, metal tabs may be used to interconnect PV strips enclosed in adjacent tiles. For example, metal tab 648 may connect the front surface of strip 632 to the back surface of strip 630, forming a series connection between strips 630 and 632. While the example of FIG. 5B shows three metal tabs interconnecting the PV strips, other numbers of metal tabs may also be used. Additionally, each solar roof tile may include fewer or more cascaded strips, which may be of various shapes and sizes.

[0061] For ease of illustration, Figures 5A and 5B do not show inter-tile spacers, which provide support between adjacent tiles and facilitate mechanical and electrical coupling. A detailed description of such inter-tile spacers can be found in U.S. Patent Application Publication No. 20190260328, entitled "INTER-TILE SUPPORT FOR SOLAR ROOF TILES," the disclosure of which is incorporated herein by reference in its entirety. Solar roof tile color matching

[0062] As shown in Figures 4C, 5A, and 5B, the PV structure and external electrodes encapsulated between the front and back covers can appear different from the background when viewed from the side of the transparent, colorless front cover. More specifically, Si-based PV structures often appear to have a blue / purple hue. While coloring the back cover can improve color matching between the PV structure and the background, it cannot solve the problem of color angular dependency. In other words, the PV structure appears to have different colors at different viewing angles, making color matching difficult. Furthermore, apart from solar roof tiles, roofs may occasionally include a certain number of "passive" or "dead" roof tiles, i.e., roof tiles without embedded solar cells. These passive roof tiles may simply include a front and back cover and the encapsulant sandwiched between the covers. The difference in appearance between solar and passive roof tiles often results in a less appealing aesthetic.

[0063] FIG. 6 shows a partial view of a roof with several solar and passive roof tiles. In FIG. 6, roof 600 may include several roof tiles arranged so that the bottom edges of tiles in an upper row overlap the top edges of tiles in a lower row, thereby preventing water leakage. Furthermore, the tiles are offset so that the gaps between adjacent tiles in one row are somewhat aligned with the centers of tiles located in a different row. In the example shown in FIG. 6, tiles 602, 604, 606, and 608 are solar roof tiles that may include a PV structure encapsulated between front and rear covers, while tiles 610 and 612 are passive roof tiles. As can be seen, the color contrast between the rear cover and the PV structure can create a "picture frame" appearance for the solar roof tiles. In fact, the PV structure often appears to "float" on the colored rear cover. Ideally, solar roof tiles 602-608 should have a similar appearance to passive roof tiles 610 and 612. The spacers 614 may fill gaps between adjacent tiles and prevent the passage of water between the PV tiles 602-608. In some embodiments, the spacers 614 may include electrical conductors that accommodate the passage of electricity and / or signals between adjacent PV tiles. In some embodiments, the spacers 614 may define paths along which wires or similar conductors may carry electricity and / or signals between adjacent PV tiles. PV roof tile feet

[0064] 7A shows a plan view of the downward-facing surface of a PV roof tile 700. Multiple feet 702 are shown attached to a PV tile backer 704. Each foot 702 includes a joining assembly 706 and a standoff 708 joined together by a neck 710. In some embodiments, the feet 702 may take the form of an injection-molded polymer part that can cooperate with the other feet 702 to support the weight of the PV roof tile 700 on a roof substrate. The feet 702 may be configured to support additional weight applied to the PV roof tile 700 from someone walking on the PV roof tile or from the PV roof tile 700 itself, which is typically formed from a backing plywood and one or more layers that help improve the overall roof's water resistance in the event of moisture intrusion from an array of roof tiles placed on top of the roof substrate.

[0065] The standoffs 708 are also configured to elevate the PV tile backer 704 above the roof substrate sufficiently to form a gap between the roof substrate and the PV tile backer large enough to accommodate the attachment of multiple electrical components to the downward-facing surface of the PV tile backer 704. In particular, a junction box 712 is shown disposed between feet 702-1 and 702-2. The junction box 712 is configured to accommodate the passage of a cable 714 through one or more openings in the PV tile backer 704. While the cable 714 is shown fixed in place to the PV tile backer 704, it should be understood that, upon installation, the cable 714 includes a male connector 716 and a female connector 718 that can be used to electrically couple adjacent PV roof tiles to one another, thereby allowing energy generated by the PV roof tiles to be collected and output for use by the home or power grid to which they are attached. Solar roof solutions also typically include an inverter configured to convert the DC power generated by the PV roof tiles to AC power ready for use by the home or power grid.

[0066] Also attached to the PV tile backer 704 are tile hooks 720. The tile hooks 720 are located near the under-roof-facing edge of the PV tile backer 704 and are configured to engage retention mechanisms of a coupling assembly disposed from the PV roof tile 700 to the under-roof PV roof tile. The tile hooks 720 also include one or more wire retention mechanisms that help secure the cables 714 to the downward-facing surface of the PV tile backer 704 when the PV roof tile 700 is being transported to a job site. Finally, the PV tile backer 704 also includes several protrusions 722 extending laterally from the roof-facing edge of the PV tile backer 704. The protrusions 722 can be used to attach additional feet to the PV roof tile 700 that are used to join adjacent PV roof tiles to one another. These feet, which also function to connect adjacent roof tiles, are shown in FIG. 7F and are described in more detail in the text describing FIG. 7F. Additional protrusions 722 , hidden by the presence of feet 702 - 1 and 702 - 2 , are also part of PV tile backer 704 and are used to help attach coupling assembly 706 of feet 702 to PV tile backer 704 .

[0067] 7B shows a top perspective view of coupling assembly 706, including a partial cross-section showing how one of protrusions 722 engages with slot 724 defined by coupling assembly 706. In particular, protrusion 722 is retained within slot 724 by cantilever beams 726 and 728, which exert an upward moment on the distal and proximal ends of protrusion 722. Upward movement of protrusion 722 is prevented by cross beam 726, which forms the upper surface of slot 724. As shown, cross beam 726 forms the upper surface of both slots 724 illustrated in FIG. 7B. The illustrated configuration allows coupling assembly 706 to be securely attached to PV tile backer 704, while still allowing for removal of foot 702 from PV tile backer 704. In particular, openings 730 in projections 722 allow a user to press on the distal ends of cantilever beams 728 to disengage them from openings 730, thereby allowing feet 702 to be withdrawn from PV tile backer 704. Once projections 722 are securely seated within slots 724, further movement is prevented by cantilever beams 728 engaged within openings 730 and retention tabs 731 located at the distal end of each projection 722. While this attachment system offers the advantage of removable feet 702, it should be understood that projections 722 can be glued to a flat, upward-facing surface of coupling assembly 706 or within channels sized to receive projections 722. Foot 702 can be secured to PV tile backer 704 only by directly gluing standoffs 708 (see FIG. 7A ) to PV tile backer 704. In some embodiments, the feet 702 may be attached to the PV tile backer 704 by a cantilever configuration as shown in FIG. 7B and by adhering the standoffs 708 to the PV tile backer 704 using an adhesive.

[0068] FIG. 7B also shows the protective cover 732 of the PV roof tile 700 and how it does not extend to cover the protrusions 722 extending laterally from the edge of the PV tile backer 704, which is configured to be oriented in an up-roof direction. FIG. 7B also clearly shows a central retention feature 734 of the multiple retention features defined by the coupling assembly 706. In particular, the entrance to the retention feature 734 is defined by a triangular alignment feature 736 including a chamfered surface configured to guide one of the tile hooks 720 into the retention feature 734. While the illustrated configuration shows the triangular alignment feature 736 including a chamfered (i.e., flat / sloped) surface 738 for guidance, it should be understood that the chamfered surface 738 can be modified to be curved (e.g., convex or concave), which may also help to align the tile hook 720 with the retention feature and facilitate entry of the tile hook 720 into the retention feature 734. The coupling assembly 706 is also configured to accommodate efficient removal of the tiles to which it is coupled. For example, if a PV roof tile requires removal or maintenance, it may be pushed up onto the roof until its hooks disengage from their respective coupling assemblies, after which its wiring is severed and it may be lifted and slid down the roof and out of position.

[0069] 7B shows how the retention feature 734 takes the form of an aperture defined by side walls 742 for establishing the horizontal position of the tile hook 720 received within the retention feature 734 and a top wall 744 for engaging the hook portion of the tile hook 720. Meanwhile, the top wall 744 is shown with a ribbed surface. It should be understood that a flat top wall could also be used to achieve similar results. The retention feature adjacent to the retention feature 734 may also include a top wall with a ribbed or flat surface. In some embodiments, the ribbed surface may reduce the amount of friction when attempting to install a tile hook into one of the retention features.

[0070] The coupling assembly 706 also includes a base 746 configured to rest against a roof substrate. In some embodiments, the base 746 includes one or more fastener openings 748 that allow the base 746 of the coupling assembly 706 to be coupled to the roof substrate using fasteners, for example, in the form of nails or screws. The coupling assembly also includes a cable guide 750 configured to prevent cables routed forward of the coupling assembly 706 from interfering with the tile hooks 720 that enter one of the retention features 734 defined by the coupling assembly 706. All of the retention features 734 may take the form of fully defined apertures to allow the hooks 720 to engage any of the retention features 734. Alternatively, the outer retention features 734-2 and 734-3 may lack outer walls that allow the outer retention features 734-2 and 734-3 to be engaged by a U-shaped bracket of a non-PV roof tile, as demonstrated in more detail below.

[0071] FIG. 7C shows a top view of the coupling assembly 706, more clearly illustrating the shape of the triangular alignment features 736. While FIG. 7C clearly illustrates a configuration including only three adjacent retention features 734, it should be understood that wider coupling assemblies 706 are also possible. For example, a wider coupling assembly may support four, five, six, or seven adjacent retention features 734, with additional triangular alignment features separating adjacent ones of the retention features 734. A wider coupling assembly 706 may be engaged by more parallel protrusions 722. For example, the coupling assembly 706 may include a slot corresponding to each triangular alignment feature.

[0072] 7D-7E show top and perspective views of the tile hook 720. In particular, the tile hook 720 includes deflectable wings 752 configured to deflect when seated between the side walls 742 of the retention feature 734-1. The deflection of the deflectable wings 752 helps to center the hook within the retention feature 734-1. A slight compression of the deflectable wings 752 can also help to establish a secure interference fit within the retention feature 734-1. The tile hook 720 further includes a plurality of wire retention channels 754 positioned on a base portion 756 of the tile hook 720 for retaining electrical cables during transport of the PV roof tile 700. While the deflectable wings 752 are shown as integrally formed at the distal end of the hook portion 756 of the tile hook 720, the deflectable wings 752 may alternatively be formed from an elastomeric material different from the material used to form the remainder of the hook portion 758. For example, rubber bumpers may be placed along opposite sides of the hook portion 758 to allow compression of the rubber bumpers while the remainder of the tile hook 720 remains rigid, preventing deformation or disengagement of the tile hook 720. It should also be understood that the deflectable wings 752 may also have a straight shape, and instead of both ends of the wing being attached to the hook portion 758 as shown in Figures 7D and 7E, only a first end of each deflectable wing 752 may be attached, and the wings may extend linearly at between 15 and 45 degrees to help center the hook portion 758 within the retention feature 734-1.

[0073] Figure 7F shows a plan view of the downward-facing surfaces of PV roof tiles 700-1 and 700-2, plus a portion of PV roof tile 700-3, with all three tiles bonded to one another. Of particular interest, Figure 7F shows how tile hooks 720 of PV roof tile 700-2 engage with retention features of coupling assembly 706 to couple PV roof tile 700-2 to PV roof tile 700-1. Figure 7F also shows foot 760, which includes coupling assemblies 762 that couple to protrusions 722 of roof tiles 700-1 and 700-3. Foot 760 differs from foot 702 because, instead of integral standoffs, foot 760 includes a support structure 764 that extends across the interface between PV roof tiles 700-1 and 700-3. The support structure 764 is configured to capture water passing through the gap between the PV roof tiles 700-1 and 700-3 and guide the water downward toward the roof, thereby preventing the water from reaching the roof substrate below the PV roof tile 700. The support structure 764 may define one or more paths to guide the water captured by the support structure 764. The paths are configured to discharge the water onto the sun-facing surfaces of roof tiles positioned below the foot 760. In addition to capturing and guiding water passing between the PV roof tiles 700-1 and 700-3, the support structure 764 also includes one or more standoffs 766 that provide structural support to the edges of the PV roof tiles 700-1 and 700-3. Incorporating multiple standoffs 766 allows for a more uniform distribution of forces experienced by the foot 760. It should be understood that the foot 760 may also include a single standoff 766 or an elongated standoff 766 to achieve a more uniform distribution of forces. 7F also shows the offset between half-tile roof tile 700-1 and roof tile 700-2. This offset allows hook 720 of PV roof tile 700-2 to engage with the joining assembly of first foot 702, foot 760 of PV roof tile 700-1 and second foot 702 of PV roof tile 700-3, as shown, thereby securely connecting the three PV roof tiles to one another. Note that other offset amounts may be considered configuration options depending on the desired roof configuration.However, the configuration shown in Figure 7F is preferred due to the robust mechanical connection established between the roof tiles.

[0074] 7G-7H show how the hook portion 758 of the tile hook 720 slides into the retention feature 734-1 of the coupling assembly 706. A cable guide 750 is shown to prevent the cable 768 from interfering with the engagement of the hook portion 758 of the tile hook 720 with the retention feature 734-1. Also shown is the neck portion 768 of the foot 702, which connects the coupling assembly 706 to the standoff 708. FIGS. 7G-7H also show how the foot 702 positions the PV roof tile 700 at a non-parallel angle relative to the surface of the roof substrate 772. This tilts the angle of the PV roof tile slightly upward, which allows the leading edge of the PV roof tile to overlap the tile positioned below it.

[0075] 8A shows a plan view of the downward-facing surface of a non-PV roof tile 800. The non-PV roof tile 800 may be formed from sheet metal with an upward-facing surface configured to match the appearance and style of the PV roof tile it will be placed next to. The downward-facing surface of the non-PV roof tile 800 may include a single standoff 802 formed from a plurality of interlocking vertical cross members 804 and horizontal cross members 806. The standoff 802 may be configured to elevate the non-PV roof tile 800 at a similar distance from and angle relative to the roof substrate as the feet 702 of the PV roof tile 700. While a single standoff 802 is used here, it should be understood that the standoff 802 may be replaced with a plurality of smaller standoffs distributed across the downward-facing surface of the non-PV roof tile 800. The standoff 802 may be adhesively bonded to the downward-facing surface of the non-PV roof tile 800. The cross-members 804 and 806 that form the standoff 802 may be formed from a polymeric material, although other materials such as ceramics and lightweight metals may also be used to form all or part of the standoff 802.

[0076] 8A also shows the non-PV roof tile 800 including a rear bracket 808 configured to engage one or more tile hooks on a PV roof tile on the roof of the non-PV roof tile 800, or alternatively, to engage one or more front bracket segments on a non-PV roof tile on the roof of the non-PV roof tile 800. The non-PV roof tile 800 includes front bracket segments 810-1 through 810-4. The front bracket segments 810 are spaced apart by a distance sized to allow passage of the coupling assembly 706 of the foot 702 or 760 of the PV roof tile 700. The non-PV roof tile 800 also includes a water channel 812 that obviates the need to equip the non-PV roof tile 800 with a separate foot 760 configured to join the non-PV roof tile 800 to an adjacent roof tile. In this manner, the water channel 812 may extend below the gap between adjacent non-PV roof tiles. The water channels 812 may be formed by bending protruding edges of the sheet metal forming the majority of the non-PV roof tiles 800 to form a path configured to collect water passing between adjacent non-PV roof tiles. In some embodiments, a lower portion of the rear bracket 808, which is configured to be secured to the roof substrate, may include a notch 814 that helps prevent damage to the rear bracket 808. The notch 814 allows a packaging team to thread a packaging strap through the notch, thereby reducing the amount of stress placed on the rear bracket 808 when securing the non-PV roof tiles 800 to a pallet for transport.

[0077] FIG. 8B shows a side view of a non-PV roof tile 800 mounted on a roof substrate 772. The shape of the rear bucket 808 shows how the rear bracket 808 has a U-shaped configuration that allows it to capture one of the tile hooks 720 and / or one or more of the front bracket segments 810. In some embodiments, the rear bracket 808 may include one or more fastener openings that allow the non-PV roof tile 800 to be secured directly to the roof substrate 772. The side view provided by FIG. 8B also shows how the vertical cross members 804 and horizontal cross members 806 may be interconnected by engaging slots defined by each of the respective cross members, which allows each cross member to extend across a majority of the width or height of the non-PV roof tile 800, as shown in FIG. 8A. FIG. 8B also demonstrates how the vertical cross member 804 may extend from one of the front bracket segments 810 all the way to the rear bracket 808. FIG. 8C shows how rear bracket 808 of under-roof non-PV roof tile 800 engages front bracket segment 810 of non-PV roof tile 800, thereby preventing upward movement of the under-roof-facing end of non-PV roof tile 800 in the event of high winds or other natural phenomena.

[0078] 8D shows a perspective view of the top of non-PV roof tile 800 along with a close-up view of water channel 812. The close-up view of water channel 812 shows how excess material at the edges of the sheet metal forming non-PV roof tile 800 can be formed to form a channel 816 configured to guide any rain or moisture from reaching the roof substrate and making its way between adjacent non-PV modules 800. Water channel 812 also includes a lip 818 configured to interlock with adjacent non-PV roof tiles and prevent inadvertent lateral movement of the non-PV roof tile during the installation process. Note that if the opposite side of non-PV module 800, which does not include water channel 812, abuts PV roof tile module 700, feet 760 can be used to prevent rain from passing between the roof tiles.

[0079] 9A-9C show various views of the coupling assembly 706 of the foot 702 of a PV roof tile 700 coupled to the front bucket segment 810 of a non-PV roof tile 800. FIG. 9A shows a top view of the coupling assembly 706-1 extending through the gap between the front bracket segments 810-3 and 810-4 such that portions of the front bracket segments 810-3 and 810-4 are secured within the retention feature 734 of the coupling assembly 706-1. While not specifically shown, it should be understood that the foot 760 attached to the PV roof tile 700 extends through the gap between the front bracket segments 810-1 and 810-2 to further secure the rear end of the PV roof tile 700 to the front end of the non-PV roof tile 800. FIG. 9B shows a close-up perspective view of the foot 702 engaging the front bracket segments 810-1 and 810-2.

[0080] FIG. 9C shows a perspective view of the underside of a PV roof tile positioned among multiple non-PV roof tiles. The coupling assembly 706 of foot 702 is shown engaged within the gap between front bracket segments 810-2 and 810-3. FIG. 9C also shows the U-shaped configuration of front bracket 810-3. FIG. 9C also includes foot 760, showing a perspective view of an exemplary foot 760. FIG. 9C illustrates the difference between standoffs 708 of foot 702 and standoffs 766 of foot 760. FIG. 9C also shows cable guides 902 of foot 702 protruding from standoffs 708 and enabling cables to remain secured to the PV tile backer 704 during transportation and the initial stages of installation of the PV roof tile 700. FIG. 9C also demonstrates how front bracket segment 810-1 fits within the rear bracket 808 of the non-PV roof tile on the roof.

[0081] 10A-10B show different combinations of PV roof tiles and non-PV roof tiles. In particular, FIG. 10A shows how PV roof tile 700 engages with non-PV roof tile 800-1, and non-PV roof tile 800-1 engages with non-PV roof tile 800-2. The connection between PV roof tile 700 and non-PV roof tile 800 in FIG. 9A functions in the same way as the connection between PV roof tile 700 and non-PV roof tile 800-1 in FIG. 10A. The connection between non-PV roof tile 800-1 and non-PV roof tile 800-2 is achieved by front bracket segments 810-1 and 810-2 of non-PV roof tile 800-2 engaging with an opening defined by a U-shaped rear bracket 808 of non-PV roof tile 800-1. Note that this connection configuration is shown in more detail in FIG. 8C.

[0082] Figure 10B shows another combination of PV and non-PV roof tiles where PV roof tiles 700-1 and 700-2 are offset by half a tile relative to non-PV roof tiles 800-1 and 800-2. Figure 10B also shows how water channels 812 cover the gaps between adjacent non-PV roof tiles 800-1 and 800-2. Note that examples of two, three, or four roof tiles joined together are shown; it will be understood that a larger mixture of PV and non-PV roof tiles could be arranged side by side in rows or courses, with the roof tiles in each row offset from the rows immediately above and below.

[0083] FIG. 11 illustrates the configuration shown in FIG. 10A with the addition of trimmed non-PV roof tiles 1102, 1104, and 1106. The trimmed non-PV roof tiles 1102, 1104, and 1106 may be manufactured by cutting full non-PV roof tiles to fit smaller areas than would otherwise be possible. While the trimmed non-PV roof tiles 1102, 1104, and 1106 are shown cut into triangular, trapezoidal, and rectangular shapes, many other shapes are possible. For example, holes can be drilled in the non-PV roof tiles to accommodate exhaust vents and other roof-surface obstructions. If the upper tier of tiles would otherwise extend beyond the roof peak, the height of the non-PV roof tiles can be reduced, resulting in rectangular roof tiles with a larger aspect ratio. Non-PV roof tiles work particularly well because they include a standoff, or in some embodiments, a plurality of standoffs, which allows the trimmed non-PV roof tile cut from the non-PV roof tile to include a sufficient amount of standoff material to maintain the desired amount of standoff from the roof substrate. In some embodiments, the non-PV roof tile can be cut as shown on-site using a circular saw or other portable saw to achieve the desired geometric shape.

[0084] 11 also shows non-PV roof tiles 800-1 and 800-2 and how they fit together with the trimmed non-PV roof tiles. In particular, the non-PV roof tile water channels are shown covering the gaps between trimmed non-PV roof tiles 1104 and 1106 and non-PV roof tiles 800-1 and 800-2.

[0085] The foregoing description of various embodiments has been presented only for purposes of illustration and description. They are not intended to be exhaustive or to limit the system to the precise form disclosed. Accordingly, many modifications and variations will be apparent to those skilled in the art. Additionally, the above disclosure is not intended to limit the system.

Claims

1. 1. A photovoltaic (PV) roof tile comprising: A protective cover and PV tile backer and a plurality of solar cells disposed between the protective cover and the PV tile backer; A foot portion, the foot portion comprising: a coupling assembly disposed on a first end of the foot, the coupling assembly defining a plurality of adjacent retention features configured to receive and prevent upward movement of one or more portions of a roof tile adjacent the PV roof tile; a foot comprising: a standoff coupled to a downwardly facing surface of the PV tile backer and positioned closer to a second end of the foot than the coupling assembly, the second end of the foot being opposite the first end of the foot; PV roof tiles comprising:

2. 10. The PV roof tile of claim 1, wherein said coupling assembly further comprises a plurality of fastener openings, each of said plurality of fastener openings configured to receive a fastener that secures said foot to a roof substrate.

3. 10. The PV roof tile of claim 1, wherein the coupling assembly comprises a plurality of angled surfaces configured to guide the one or more portions of the adjacent roof tiles into one or more of the plurality of adjacent retention features during roof installation.

4. 10. The PV roof tile of claim 1, wherein the coupling assembly comprises a plurality of triangular alignment features that separate a plurality of adjacent retraining features and serve to guide the one or more portions of the roof tile into one or more of the plurality of adjacent retention features.

5. 5. The PV roof tile of claim 4, wherein each of said triangular alignment features comprises a cable guide that prevents wires routed in front of said coupling assembly from blocking said plurality of adjacent retention features.

6. 10. The PV roof tile of claim 1 further comprising a tile hook attached to the downwardly facing surface of the PV tile backer.

7. 7. The PV roof tile of claim 6, wherein the tile hook is configured to engage a central one of a plurality of adjacent retention features of a PV roof tile foot coupling assembly under the roof of the PV roof tile.

8. 7. The PV roof tile of claim 6, further comprising a plurality of hooks attached to the downwardly facing surface of the PV tile backer.

9. 7. The PV roof tile of claim 6, wherein the tile hook comprises one or more deflectable surfaces configured to flex to form an interference fit between the tile hook and an opposing wall defining one of the plurality of retention features of the coupling assembly.

10. The PV roof tile of claim 6 , wherein said tile hook defines a plurality of wire retention paths.

11. 2. The PV roof tile of claim 1, wherein an upwardly facing surface of the coupling assembly defines a plurality of adjacent slots, and wherein the PV tile backer comprises a plurality of parallel protrusions extending laterally from one side of the PV tile backer, and a subset of the plurality of parallel protrusions extending into the plurality of adjacent slots of the coupling assembly to secure the coupling assembly to the PV tile backer of the PV roof tile.

12. 12. The PV roof tile of claim 11, wherein a first slot of said plurality of slots is defined by a first cantilever beam, a second cantilever beam, and a cross beam.

13. 13. The PV roof tile of claim 12, wherein a first protrusion of a subset of said plurality of parallel protrusions extends within said first slot, said first cantilever beam exerts a first force in a first direction on a distal end of said first protrusion, said second cantilever beam exerts a second force in the first direction on a proximal end of said first protrusion, and said cross beam is opposedly disposed between said first cantilever beam and said second cantilever beam and exerts a third force in a second direction opposite said first direction.

14. 10. The PV roof tile of claim 1, wherein each foot further comprises a neck portion that joins the standoff to the coupling assembly and leaves a gap between the neck portion and the PV tile backer, the gap being sized to accommodate the passage of one or more electrical cables.

15. 10. The PV roof tile of claim 1, wherein an outer retention feature of the plurality of adjacent retention features is configured to receive an adjacent front bracket segment of a non-PV roof tile on a roof from the PV roof tile.

16. 10. The PV roof tile of claim 1, wherein said plurality of solar cells comprises a first edge bus bar located near an edge of a first surface and a second edge bus bar located near an opposing edge of a second surface, said plurality of solar cells being arranged such that the first edge bus bar of a first solar cell overlaps the second edge bus bar of an adjacent solar cell, thereby resulting in said plurality of solar cells forming a string coupled in series.

17. 10. The PV roof tile of claim 1, wherein the standoff comprises a first surface that directly contacts the PV tile backer and a second surface opposite the first surface that is configured to contact a roofing substrate.

18. 18. The PV roof tile of claim 17, wherein said first surface is anti-parallel to said second surface.

19. 10. The PV roof tile of claim 1, wherein said plurality of retention features comprises a central retention feature defined by opposing side walls and a raised top wall, said raised top wall configured to engage a hook portion of a tile hook disposed on said PV roof tile from said PV roof tile to a PV roof tile on a roof.

20. 10. The PV roof tile of claim 1, wherein said plurality of retention features comprises: a first outer retention feature comprising a first raised top wall and a first side wall facing in a first direction; and a second outbound retention feature comprising a second raised top wall and a second side wall facing in a second direction opposite said first direction.

21. a first roof tile directly bonded to a roof substrate, said first roof tile comprising: a first protective cover; a first PV tile backer; a first plurality of solar cells disposed between the first protective cover and the first PV tile backer; a first roof tile comprising a plurality of feet, each foot being positioned between the PV tile backer and the roof substrate and comprising a coupling assembly projecting laterally from beneath the PV tile backer; a second roof tile positioned on the roof from the first roof tile, the second roof tile comprising: a second protective cover; a second PV tile backer; and a second plurality of solar cells disposed between the second protective cover and the second PV tile backer; a second roof tile coupled to a downwardly facing surface of the second PV tile backer and comprising: a tile hook comprising a hook portion that engages within a retention feature of the coupling assembly of a first foot of the plurality of feet; A roof with a.

22. a third roof tile positioned on the roof from the first roof tile and abutting the second roof tile; 22. The roof of claim 21, wherein a third roof tile comprises a plurality of front bracket segments positioned proximate a first edge of the third roof tile, a first front bracket segment of the plurality of front bracket segments being positioned within a first retention feature of the joining assembly of a second foot of the plurality of feet, and a second front bracket segment of the plurality of front bracket segments being positioned within a second retention feature of the joining assembly of the second foot of the plurality of feet.

23. 23. The roof of claim 22, wherein the first front bracket segment is separated from the second front bracket segment by a gap sized to accommodate passage of at least a portion of the second foot of the plurality of feet.

24. 23. The roof of claim 22, wherein the sun-facing surface of the third roof tile has a non-rectangular shape.

25. 23. The roof of claim 22, wherein the third roof tile does not include a solar cell.

26. 23. The roof of claim 22, wherein the third roof tile comprises standoffs formed from a plurality of vertical and horizontal cross-members spanning a majority of the downwardly facing surface of the third roof tile.

27. 22. The roof of claim 21, wherein the second protective covering overlaps a portion of the first protective covering.

28. 22. The roof of claim 21, wherein the coupling assembly comprises a plurality of adjacent retention features.

29. 22. The roof of claim 21, wherein the retention feature of the coupling assembly of the first foot is defined at least in part by a raised upper wall that impedes upward movement of the tile hook.

30. 22. The roof of claim 21, wherein each foot of the plurality of feet further comprises a standoff coupled to the coupling assembly by a neck.

31. 23. The roof of claim 22, wherein the second roof tile comprises a second foot comprising a support structure that supports a first lateral edge of the second roof tile and a second lateral edge of the third roof tile, the support structure defining one or more channels configured to capture and direct rain passing between the first roof tile and the second roof tile.

32. 32. The roof of claim 31, wherein the support structure comprises a plurality of standoffs.

Images