Patent Description:
A photovoltaic (PV) cell generates electricity in response to light striking a surface of the cell material. In particular, a PV cell may be placed in sunlight to generate electricity from the sunlight striking the cell. Individual PV cells may be arranged in groups in a sheet of material to form a PV panel capable of generating a useful amount of electricity for storage or for immediate use in electrically powered devices. PV generating capacity has grown exponentially within the past few decades and is an ever-increasing percentage of distributed energy production within the United States and around the world.

PV panel arrays are commonly installed on commercial and residential rooftops to make use of that area for power generation. For low-slope roofs (commonly defined as having no more than four inches of rise over every twelve inches of run) a PV panel array may be installed with a racking system that is ballasted with weights to hold it down. There is no need for any rooftop penetrations in these low-slope roofs because the PV panels and racking are held by the weight of the ballast rather than a mechanical attachment to the roof structure. For steep-sloped roofs (commonly defined as having over four inches of rise for every twelve inches of run) PV panel array installation requires a racking system that must be mechanically attached to the roof structure. This mechanical attachment generally requires penetrations to be drilled through the rooftop, so that the system can be bolted to the underlying building structure. The hardware of the penetration is then flashed and waterproofed to the extent possible to prevent leakage.

Both low-slope and steep-sloped roof PV panel installations present problems, both practical and aesthetic. First, any rooftop PV panel installation that requires roof penetrations presents the problem of potential leakage and expensive repairs for leakage damage within the structure and for preventing further leakage. With regard to steep-sloped shingle roofs, the roof penetration and hardware installation may break the mastic sealant which helps hold the rows of shingles in place during high wind events, and thus leave the roof prone to wind damage. While ballasted PV panel racking systems which may be installed on low-slope roofs are typically less expensive to install and may be installed relatively quickly, the ballast weight adds to the load on the roof structure and thus the roof structure must be designed to take the added load. For some buildings a ballasted PV panel racking system may only be added after the building structure is modified to properly support the added weight. Both low-slope and steep-slope roof PV panel installations must also be designed for high and variable wind conditions and dangers from seismic events, and must be tested in order to be certified to UL standards for resistance to wind and seismic events. Additionally, rooftop PV panel installations present relatively dangerous working conditions both for installation work and maintenance since the installations are necessarily at height. The danger for workers is particularly acute for steep-slope installations where a worker may easily slide off the roof and suffer a debilitating or even fatal fall. Rooftop PV panel installations also present problems when maintenance is required for the roof or the roofing material must be replaced. Such roofing repair or replacement may require the entire rooftop PV panel array to be removed and then reinstalled once the roofing repair or replacement is done.

In both low-slope and steep-slope roof installations, the PV panels provide a visual distraction to the roofing surface and the building aesthetic. This is particularly the case for steep-slope roof installations where the PV panels are clearly visible from generally every viewpoint to the building. Even in low-slope PV panel installations, some or all of at least some of the PV panels or the racking system may be visible from at least some points of view to the building and may affect the building aesthetics.

There have been a number of attempts to minimize the visual impact of the PV panel array in rooftop installations. <CIT> discloses a PV module particularly for use in rooftop installations. The PV module, which may include a number of individual PV cells, includes a color layer with pigments that cause the PV module to simulate conventional roofing. Another attempt to make a rooftop PV installation less apparent and visible is to incorporate the PV cells into a roofing material or shingle that is applied into a field of conventional roofing material. This approach is illustrated by Dow Powerhouse® shingles. However, these types of shingles do not blend in well with surrounding roofing shingles, and this may cause the installation to have a negative impact on the building aesthetics. Another drawback of incorporating PV cells into a roofing shingle is that it greatly multiplies the number of electrical connections that must be made in the PV installation, which increases both points of potential failure and installation labor. Yet another drawback of incorporating PV cells into roofing shingles is the heat build-up occasioned by having the PV cells directly on the roof deck and roofing underlayment with no means of cooling the cells. Conventional PV panel array installations rely on air flow beneath each PV panel to isolate the PV cells from the rooftop temperatures which can reach fifty to one hundred degrees hotter than the ground ambient temperature. Preventing undue heat buildup in a PV cell is important because the heat buildup can lead to a large drop in output from the PV cell.

Yet another attempt to hide PV rooftop installations has been developed by Tesla Corporation where the PV cells are incorporated into glass shingles of tiles and these PV-integrated shingles or tiles are installed together with "blank" shingles or tiles which do not incorporate PV cells. This arrangement is intended to provide a single continuous appearance across the entire roofing installation. However, this system requires a large amount of electrical connections and also suffers from the heat buildup problem described above. In addition, the shingles or tiles are relatively heavy and require that the underlying structure be designed to accommodate the additional weight of the roofing material. The labor to install such a system is also more than a standard roof and the economics of the roofing material and labor may make it cost prohibitive.

All rooftop PV device installations also have the disadvantage of having to meet strict code requirements of electrical, fire, mechanical, and other regulations that are triggered when they are placed upon rooftops. If one does not want to deal with the restrictions, limitations and costs associated with mounting a PV panel array on a rooftop, one could consider a ground mounted system where the array is placed on elevating poles or structure on adjacent ground area to the building. However, a major limitation of such elevated ground installations is that residential homes have limited area that is typically reserved for lawns, patios, sidewalks and other features demanded by residential homeowners. Commercial properties too may have limited free ground area for such elevated ground PV panel array installations. Furthermore, elevated ground PV panel arrays in a residential or commercial setting can be more aesthetically distracting than a roof mounted array.

<CIT> and <CIT> both disclose PV panel assemblies which may be used for paving roads, driveways, and walkways. These panel assemblies, however, have a distinctively non-traditional appearance and do not provide a cost-effective or aesthetically pleasing installation that would be readily accepted by commercial building owners or home owners.

<CIT> discloses a photovoltaic road block comprising a frame which encompasses a concrete floor and a photovoltaic module consisting of a power generation assembly provided between two glass layers. The photovoltaic module is provided above the concrete floor and separated therefrom by means of a horizontal part of the frame. A waterproof sealing layer is provided on the upper side of the concrete floor.

It is an object of the invention to provide devices and systems which overcome the above-noted problems and others associated with PV panel installations. These problems are addressed by providing landscape pavers for ground installation of PV panels and by providing PV panel installations using such pavers. By facilitating the installation of PV panels in landscape features such as walkway and patio hardscapes, for example, the pavers and installations according to the present invention allow these hardscape areas to be used for electrical power generation without interfering with the property aesthetics and without taking up property area only for such power generation.

A landscape paver according to one aspect of the present invention as defined in claim <NUM> includes a PV panel and a rigid frame. The PV panel has a panel first surface and a panel second surface each bounded by a panel peripheral edge. The PV panel includes one or more PV cells and is operable to provide electrical power at a panel output terminal in response to operating light incident on the panel first surface. The rigid frame extends along the panel peripheral edge and defines a frame inside surface which, together with the panel second surface, defines a base volume. A molded base material is located in the base volume with a base material backing surface molded against at least a portion of the panel second surface and a base material lateral surface molded against at least a portion of the frame inside surface. A light-transmissive paver cover material extends over the panel first surface and preferably over at least a portion of a frame outside surface which faces away from the base volume.

In a paver structure according to this first aspect of the invention, the molded base material provides a rigid support for the PV panel which allows the paver to be placed on the ground or a prepared sand bed. The rigid frame provides a form for receiving the base material in the manufacture of the paver. The light-transmissive paver cover material extending over the panel first surface provides a tough and wear-resistant material to protect the panel first surface from footsteps and the weight of objects placed on the installed paver. However, light and sunlight in particular may still penetrate through the paver cover material to reach the PV panel first surface and cause the panel to generate electricity. Thus a paver according to this first aspect of the invention may be installed in a landscape, preferably with other such pavers, and the panel output terminal connected to provide electrical generation for current use or storage in an electrical storage system such as a battery system.

As used in this disclosure and the accompanying claims, the designation "PV panel" refers to a device having one or more PV cells which produce a photovoltaic effect in response to operating light incident on a surface of the cell. "Operating light" is used herein to refer to the level of light needed for the PV cell to produce the photovoltaic effect. Such PV cells may be formed in any fashion using any photovoltaic material technology now known or developed in the future. For example, a solar cell which may be used in a PV panel in accordance with the present invention may comprise a monocrystalline, polycrystalline, or amorphous silicon cell, thin film PV cell, multi-junction PV cell, or any other type of PV cell. In accordance with current manufacturing techniques, a number of PV cells which individually provide a small light collection area are typically connected together to form a PV panel which overall provides a large light collection area. However, the designation "PV panel" as used in this disclosure and accompanying claims is not limited to such multiple PV cell arrangements. Also a PV panel as used in this disclosure will commonly include a sheet of backing material and a sheet of transparent upper surface material in the PV panel structure. These backing and upper surface materials serve to protect the PV cells, conductor traces, and other electronic elements which may be included with the PV cells.

The designation "light-transmissive" as used in this disclosure and the accompanying claims means that the material or structure is capable of transmitting operating light to the collection surface of a PV cell, that is, sufficient light to, when the light is incident on the surface of a PV cell, cause the PV cell to generate electricity. A light-transmissive material need not transmit all wavelengths equally, and may essentially block or greatly attenuate some wavelengths in the spectrum of sunlight. Regardless of any such wavelength transmissivity preference, sufficient light at a given wavelength may pass through the light-transmissive material in the thicknesses used in the structures described herein to cause a PV cell operable on that wavelength to produce the photovoltaic effect to generate electricity. Of course, implementations according to the various aspects of the invention may use highly light-transmissive materials to allow for higher levels of electricity generation from installations according to the present invention.

The present disclosure and accompanying claims may use terms such as top, bottom, side, lateral, upper, and lower in reference to a certain feature or structure. These relative positional terms are used with reference to the orientation of the example pavers and paver installations shown in the drawings.

In some implementations of a paver according to the first aspect of the invention, the rigid frame includes a panel support flange extending from the frame inside surface. This panel support flange defines a peripheral sealing surface abutting a portion of one of the panel first surface and panel second surface to facilitate the containment of the base material as it is introduced into the base volume during the molding process. In addition to the panel support flange, the paver may include a panel capture flange to form a panel receiving channel which receives the peripheral edge of the PV panel.

Regardless of how the PV panel is positioned or connected to the frame prior to introduction of the material which forms the molded base material of a paver according to the first aspect of the invention, a portion of the frame may be exposed on a bottom surface of the paver. Where the frame is formed from an electrically conductive material, this exposed portion of the frame provides a grounding point for the paver.

Implementations of a paver according to the first aspect of the invention may also include reinforcing elements embedded in the molded base material to enhance the strength of the composite structure made up of the PV panel, frame, molded base material, and cover material. Such reinforcing elements may be included in spaced apart layers of reinforcing fibers or other elements within the thickness of the molded base material and may extend substantially parallel to the panel plane defined by the PV panel first surface.

The paver cover material included in pavers according to the first aspect of the invention may be a material molded on to the PV panel and frame. In this case, a layer of the molded cover material defines a lower cover material surface which is molded against the panel first surface and defines a cover material upper surface facing away from the panel first surface. Also in these molded cover material embodiments, a cover material inside lateral surface may be molded against the frame outside surface.

A paver according to the first aspect of the invention may include at least one reduced light transmissivity layer located in the cover material between a paver load receiving surface and the panel first surface. Any such reduced light transmissivity layer is formed from a light-transmissive material in which is included low-light-transmissivity granular material. "Low-light-transmissivity" in this sense and as used elsewhere in this disclosure and the accompanying claims means that the granular material transmits less than approximately <NUM>% of incident light in the operating spectrum of the given PV panel. This low-light-transmissivity granular material serves to provide an appearance to the paver that may mimic a traditional landscape paver of concrete, stone, or other traditional paver material. The appearance may be enhanced by the color presented by the panel first surface visible through the light transmissive cover material and by granular material which exhibits a light transmissivity greater than a low-light-transmissivity material and may be included in the reduced light transmissivity layer or elsewhere in the paver above the PV panel. In some cases the low-light-transmissivity granular material may be suspended in the reduced light transmissivity layer, or may be embedded in the paver load receiving surface, or both. In any event the low-light-transmissivity granular material is preferably present in such a concentration that it reduces the light transmissivity of the reduced light transmissivity layer by no more than approximately <NUM>%. That is, the concentration of low-light-transmissivity material in the reduced light transmissivity layer is preferably limited to a concentration in which the low-light-transmissivity material reduces the light transmissivity of the layer by no more than approximately <NUM>% as compared to a case in which no low-light-transmissivity material was included in the layer. Also, the grains which make up the low-light-transmissivity granular material may be limited to a certain size ranges to produce the desired appearance while avoiding undue impact on the amount of light which may reach the PV panel.

A second aspect of the invention as defined in claim <NUM> encompasses a PV panel installation which employs pavers according to the first aspect of the invention. A PV panel installation according to this aspect of the invention includes a PV panel supporting bed and a moisture introduction arrangement in fluid communication with the PV panel supporting bed. The PV panel supporting bed in these installations is formed as a layer of granular material such as a layer of paver sand which produces a porous and permeable layer of material above a suitable subgrade.

According to this second aspect of the invention, the PV panel is integrated with materials to form a paver according to the first aspect of the invention. In these implementations the PV panel is set in the PV panel supporting bed through the integrated paver material such as the frame and molded base material described above.

Regardless of which type of PV panel is used in such an installation, the moisture introduction arrangement allows water to be released into the porous and permeable layer formed by the granular material making up the PV panel supporting layer. This introduced water and the evaporation of the water serves to moderate the temperature of the PV panel supporting bed and thereby moderate the temperature the PV panel in the installation. This moderation of temperature allows the PV panel to operate more efficiently and compensates for any loss of efficiency cause by the reduction of light incident on the panel through the pavers. In particular, the moderation of temperature helps compensate for the reduction of light reaching the PV panel occasioned by any reduced light transmissivity layer in the paver or pavers.

In installations according to this second aspect of the invention the moisture introduction arrangement may include at least one conduit extending through the volume defined by the PV panel supporting bed. The conduit incorporates suitable emitters or is formed at least partially from a water-permeable material to facilitate the communication of water from the conduit to the porous and permeable layer comprising the PV panel supporting bed.

An installation as described above and in further detail below in connection with the drawings, functions to provide a PV panel array that may be identical or very similar in appearance to that of a conventional landscape paver patio, walkway or drive located in a property landscape while simultaneously providing solar generated electricity. The sun energy moves through the atmosphere and strikes the top surface of the light transmissive landscape pavers and travels through the light-transmissive paver materials and then into the PV panel where the electricity is generated. Where included in the installation, the moisture introduction arrangement (which may comprise low volume drip irrigation lines) provides cooling to the PV panels including any associated electronics, such as batteries and micro-inverters, through the heat absorbing capacity of the water and through the cooling occasioned by evaporation of the introduced water. The light-transmissive landscape pavers can be installed in a configuration to form areas of a patio, walkway, or drive of uniform appearance which blends in well or is even indistinguishable from adjacent areas formed from traditional, non-PV generation enabling, paver materials.

The PV panel installation according to the various aspects and feature of the invention has the following advantages:.

These and other aspects of the invention and advantages and features of the invention will be apparent from the following description of representative embodiments, considered along with the accompanying drawings.

<FIG> show embodiments that are not according to the present invention and are present for illustrating purposes only.

<FIG> shows a perspective view of a composite landscape paver <NUM> in accordance with aspects of the present invention in which a PV panel is incorporated into the paver structure. As indicated in the figure, it is not apparent at least from the illustrated perspective that paver <NUM> incorporates a PV panel. The outward appearance from this perspective provides the appearance of a traditional square paver with a top surface <NUM> (representing a load receiving surface for the paver) and in the case of this square example, four side surfaces <NUM> including the two such surfaces visible from this perspective. The hidden lines shown in <FIG> show the outline of a rigid frame <NUM> which is included in composite paver <NUM>. Rigid frame <NUM> is associated with a PV panel included in paver <NUM> and shown and described in connection with the section view of <FIG>. However, depending upon the particular construction of the paver using low-light-transmissivity granular material in the construction of paver <NUM> as discussed in detail below, the rigid frame <NUM> and the PV panel may not be discernable as such from the perspective shown in <FIG>. In this example, the only indication that paver <NUM> incorporates a PV panel is the arrangement of two pairs of leads <NUM> and <NUM> protruding from a bottom surface of the paver not visible in this perspective.

It should be appreciated that the square shape of paver <NUM> is simply provided as an example and that pavers according to the present invention may be formed in any desired shape. Pavers according to the invention may provide a top surface in the shape of an elongated rectangle or other polygonal shape, or a circle, oval, or other non-polygonal shape. Also, although <FIG> shows that the top surface <NUM> and side surfaces <NUM> of paver <NUM> includes slight undulations or contours across the surfaces, each surface remains substantially planar. Various features or roughness may be molded or otherwise provided in particularly top surface <NUM> to provide a generally planar, nonslip surface appropriate for use as a walking surface. Also, pavers embodying principles of the invention such as example paver <NUM> and the other example pavers described herein may have any suitable dimensions, including common traditional paver dimensions. For example, paver <NUM> may be approximately <NUM> inches by <NUM> inches and approximately <NUM> inches thick.

The section view of <FIG> shows that the PV panel shown generally at <NUM> and frame <NUM> are included in paver <NUM> between a molded base material <NUM> and a paver cover material <NUM>. PV panel <NUM> has a panel first surface <NUM> and a panel second surface <NUM>. These two surfaces <NUM> and <NUM> are bounded by a peripheral edge <NUM>. In this example implementation, peripheral edge <NUM> of PV panel <NUM> forms generally a square shape in top plan view to maximize the surface area of panel first surface <NUM> in paver <NUM>. Operating light incident on panel first surface <NUM> produces a photovoltaic effect so that PV panel <NUM> is operable to provide electrical power at a panel output terminal, defined in this case by either of the two pairs of leads <NUM> and <NUM> shown in both <FIG>. The example PV panel <NUM> includes a junction box <NUM> located on the panel second surface <NUM>. Junction box <NUM> may include electronic components associated with panel <NUM> and terminals for the positive and negative wires of leads <NUM> and the positive and negative wires of leads <NUM>. It will be appreciated that PV panels such as panel <NUM> may, depending upon the PV technology employed, be formed from multiple layers of semiconductor materials together with other structures such as conductor traces, all encapsulated between one or more layers of backing material and one or more layers of glass or other transparent cover material. Since the present invention encompasses any PV technology for producing a PV panel, and since in any event the internal structure of the PV panel is not relevant to an understanding of the present invention, each PV panel shown in section in the drawings is shown without any internal detail.

<FIG> shows that rigid frame <NUM> in the example embodiment of <FIG> includes a frame member <NUM> that extends in a height dimension perpendicular to a plane defined by panel first surface <NUM>. In this example, and as is apparent from the hidden lines shown in <FIG>, frame member <NUM> extends along the entire panel peripheral edge <NUM>. A frame inside surface <NUM> together with the panel second surface <NUM> defines a base volume while a frame outside surface <NUM> faces away from the base volume. The molded base material <NUM> is located in the base volume and in this example fills the entire base volume so as to define most of a bottom surface <NUM> of paver <NUM>. In particular, molded base material <NUM> includes a base material backing surface which is molded against at least a portion of panel second surface <NUM> and a lateral surface which is molded against at least a portion of the frame inside surface <NUM>. The example of <FIG> shows two different spaced apart layers of reinforcing material <NUM> include in the molded base material <NUM> to improve the strength characteristics of paver <NUM>, and particularly, improve resistance to bending from a plane parallel to the plane of panel first surface <NUM>.

Paver cover material <NUM> extends over the panel first surface <NUM> and preferably, but not necessarily, over at least a portion of the frame outside surface <NUM>. In this example, paver cover material <NUM> extends over substantially all of the frame outside surface <NUM> to define all of the sides <NUM> of paver <NUM>. Paver cover material <NUM> is comprised of a light transmissive material at least in portions extending over one or more areas of panel first surface <NUM> and preferably over the entire panel first surface. As will be discussed below, paver cover material <NUM> may include a material which is molded over the PV panel and frame to define a lower cover material surface molded against the panel first surface and a cover material inside lateral surface molded against the frame outside surface.

In the example of <FIG> frame <NUM> includes a panel support flange <NUM> extending from frame inside surface <NUM>. This panel support flange <NUM> defines a peripheral sealing surface <NUM> abutting a portion of panel second surface <NUM> in this case. This example frame <NUM> further includes a panel capture flange <NUM> which together with panel support flange <NUM> defines a panel receiving channel which captures peripheral edge <NUM> of PV panel <NUM> around the entire peripheral edge. In the example of <FIG> at least a portion of frame <NUM> is exposed on bottom surface <NUM> of landscape paver <NUM>. Where the frame comprises an electrically conductive material such as aluminum, this exposed portion of frame <NUM> provides a ground point for the PV panel when the paver is placed in an installed position as will be described further below in connection with <FIG>. Alternatively, the entire frame <NUM> may be completely encapsulated within base material <NUM> and cover material <NUM> so that the frame is isolated from the environment.

In order to produce an appearance approximating a traditional landscape paver, paver <NUM> includes a reduced light transmissivity layer <NUM> shown in <FIG> as a thin layer of material which includes the paver top surface <NUM>. This reduced light transmissivity layer <NUM> includes a light transmissive material <NUM> in which is embedded or otherwise included low-light-transmissivity granular material <NUM> as shown in the enlarged view of <FIG>. The low-light-transmissivity granular material may comprise grains of sand, quartz, plastics, combinations of these materials, and or other suitable low-light-transmissivity granular materials to produce the desired appearance. While the grains <NUM> of low-light-transmissivity granular material will block some of the incident light from passing through from paver top surface <NUM> to panel first surface <NUM>, the granular material is preferably included in such a concentration so as to reduce the overall light transmissivity of the reduced light transmissivity layer by no more than approximately <NUM>%, that is, <NUM>% as compared to the light transmissive material <NUM> in layer <NUM> if the material included no such granular material. The low-light-transmissivity granular material positioned over one or more areas of the reduced light transmissivity layer <NUM> may be made up of grains having a maximum dimension between approximate <NUM> microns and approximately <NUM> microns, and preferably between approximately <NUM> microns and approximately <NUM> microns.

<FIG> shows an alternative paver construction in a paver <NUM> including a rigid frame <NUM> having a different configuration as compared to frame <NUM> shown in <FIG>. This alternate embodiment includes a PV panel <NUM>, molded base material <NUM>, and cover material <NUM> similar to the embodiment shown in <FIG>. However, frame <NUM> includes tube structure including an outside member <NUM> and an inside member <NUM>. Outside member <NUM> in this embodiment forms the frame outside surface <NUM> facing cover material <NUM>, while inside member <NUM> forms the frame inside surface <NUM>. Frame <NUM> also includes a base member <NUM> which is exposed at the paver bottom side <NUM>. Base member <NUM> also includes a lip <NUM> which projects from inside surface <NUM>. The example frame <NUM> shown in <FIG> also includes studs <NUM> which may be spaced apart along the frame inside surface <NUM> along the length of the frame to further strengthen the composite structure.

The alternative paver construction shown in <FIG> also includes an access opening <NUM> formed in the molded base material <NUM> to provide access to panel junction box <NUM>. In this alternate construction, lead pairs <NUM> and <NUM> extend through the access opening rather than being embedded in the molded base material as shown in the example of <FIG>.

The example of <FIG> also shows a GPS electronic module <NUM> operatively connected to a battery <NUM> for supplying power to the GPS electronic module. In this example GPS electronic module <NUM> and battery <NUM> are contained in PV panel junction box <NUM> although it will be appreciated that these elements may be located in a separate junction box or placed in another location within the paver structure. A small portion of the PV panel output in this arrangement may be used to charge battery <NUM>. Suitable electronic components for providing the desired charging may be housed within junction box <NUM> or elsewhere in the paver. GPS electronic module <NUM> may be in wired or wireless communication with appropriate receiving hardware located in paver <NUM> or remotely to provide spatial location of the module and therefore the composite paver <NUM> in which it is located. In addition to providing spatial location information, GPS electronic module <NUM>, or a separate electronic module located in junction box <NUM> or elsewhere in the structure of paver <NUM>, may include electronic components for monitoring and collecting performance data for the paver such as power output, paver temperature, and cumulative power output, for example. This performance data for paver <NUM> may be communicated from GPS electronic module <NUM> or other module to monitoring and reporting components for the PV panel system in which paver <NUM> is included.

The alternate paver construction shown in <FIG> also includes a different configuration for the reduced light transmissivity layer as compare to that shown in <FIG>. In the example of <FIG>, all of cover material <NUM> makes up the reduced light transmissivity layer including low-light-transmissivity granular material <NUM>. However, it should be appreciated that implementations according to the present invention are not limited to the two arrangements for the reduced light transmissivity layer shown in <FIG> and <FIG>. For example, another arrangement within the scope of the present invention includes a distinct reduced light transmissivity layer spaced apart from both the paver top surface and from the surface of the cover material facing the PV panel. Additionally, there may be multiple reduced light transmissivity layers in the cover material over the PV panel. More generally, the reduced light transmissivity layer or layers may be formed at any location of the cover material and in any fashion to incorporate the low-light-transmissivity granular material. In any of these arrangements, the granules of low-light-transmissivity material in one or more layers above the PV panel first surface together with coloration of the PV panel first surface (and the coloration of any upwardly facing frame surfaces) allows the landscape paver to match or at least approximate the appearance of a traditional paver appropriate for walkways, patios, and other hardscapes.

Numerous types of materials may be used for forming the frame, such as frames <NUM> and <NUM>, shown in <FIG> and <FIG>, respectively. For example, the rigid frame may be formed from aluminum or other suitable metals. These frames may also be formed from plastics. Also, because the frame may be completely encapsulated and protected within the paver cover material, the frame may be formed from fiber board and similar materials.

Base material such as that shown at <NUM> and <NUM> in <FIG> and <FIG>, respectively, may comprise concrete or any other suitable material which may be molded within the paver frame. Where concrete is used it may include lightening materials and additives to provide the desired strength and weight characteristics for the completed paver.

The cover material which may be used in a composite paver according to the present invention may comprise a suitable clear polymer resin, epoxy, pourable clear plastic polymer, or any clear, moldable material which provides the desired light transmissivity when the material is cured or hardened.

It should also be appreciated that any of the features shown in the two example configurations of <FIG> and <FIG> may be used in other configurations within the scope of the present invention. For example, although reinforcing material <NUM> is shown only in the embodiment of <FIG>, such material may also be included in any other embodiment including the embodiment of <FIG>. Likewise, the studs <NUM> shown in the example of <FIG>, may be included in any other embodiment, including the embodiment of <FIG>.

The composite paver structure shown for example in <FIG> and <FIG> may be formed in any suitable process. One preferred fabrication process includes first forming the PV panel and frame arrangement, and supporting this arrangement inverted from the position shown in the figures so that the frame inside surface (<NUM> in <FIG>) and panel second surface (<NUM> in <FIG>) form an upwardly facing receptacle for receiving base material in liquid or flowable form. Since the base material may be fairly heavy, good support may be needed for the PV panel to prevent bending in the PV panel under the load of the base material before it solidifies. Also, forms may be required to provide any desired features in the base material, such as the access opening <NUM> shown in <FIG>.

Once the base material is placed in the above-noted upwardly opening receptacle formed by the frame and PV panel, and solidifies appropriately, the resulting intermediate structure of PV panel, frame, and base material may be placed in a suitable mold which allows the cover material to be molded on to the structure. For example, the intermediate structure may be placed PV panel side down into a mold which leaves a gap into which the cover material may be poured, injected, or otherwise placed. It is also possible to partially prefill the mold and press the intermediate structure into the partially filled mold to form the desired cover layer. Once the cover material has hardened sufficiently, the resulting structure may be removed from the mold for any further processing or assembly.

Any low-light-transmissivity granular material desired for a give implementation may be introduced into the structure in a number of ways within the scope of the present invention. For example, the granular material may be spread out across the bottom of the mold used to mold the cover material onto the intermediate structure. This process produces a reduced light transmissivity layer generally as shown in the example of <FIG> and <FIG>. Alternatively, the low-light-transmissivity granular material may be mixed uniformly with the cover material prior to being molded on to the intermediate structure to produce a reduced light transmissivity layer as shown in the example of <FIG>. In yet other techniques, the cover material may be molded on in multiple layers, any one or more of which may contain the low-light-transmissivity granular material.

The view of <FIG> may be used to described a landscape paver installation employing PV panel integrated pavers such as those shown in <FIG>. Installation <NUM> includes a PV panel supporting bed <NUM> formed on a subgrade <NUM>. PV panel supporting bed <NUM> includes a layer of granular material above subgrade <NUM>, preferably a granular material such as paver sand. A moisture introduction arrangement is in fluid communication with PV panel supporting bed <NUM>. In this case the moisture introduction arrangement includes at least one conduit <NUM> extending through the volume defined by PV panel supporting bed <NUM>. Conduit <NUM> may include periodic emitters or may be formed in part or in sections of a permeable material to allow water directed through the conduits <NUM> to escape into the granular material comprising PV panel supporting bed <NUM>.

The example of <FIG> shows multiple pavers <NUM> set in PV panel supporting bed <NUM> so as to be supported by the bed of granular material. The PV panels <NUM> integrated in pavers <NUM> are shown connected in series by lead pairs <NUM> and <NUM>. Each of these connections may be formed from a suitable waterproof connector <NUM> such as an MC-<NUM> connector for example. Although not shown <FIG>, it will be appreciated that these lead pairs <NUM> and <NUM> are connected to the leads of other such pavers to form an array of series connected panels which is ultimately connected by suitable means to further equipment associated with the array. In particular, panels such as panels <NUM> shown <FIG> may be connected in series to an inverter as is known in the field of PV panel arrays. However, the present invention is not limited to any particular arrangement for connecting the various PV panels of an array of pavers. For example, PV panels according to the invention may be connected in parallel with each other rather than in series. Also, any additional electrical equipment may be included in an installation such as installation <NUM> to enhance the performance or otherwise affect the performance of the PV panel array including optimizers and other circuitry that may be associated with each panel or groups of panels in the installation.

Regardless of how the PV panels in the composite pavers are connected to equipment for extracting power from the array, the paver provides cover material <NUM> as a light transmissive layer above each panel so that light, especially sunlight, incident on the paver may pass through to the PV panel. The light transmissive layer also serves to protect the relatively fragile PV panel surfaces from contact and also serve as a carrier for the granular material described above which provides the desired appearance for the pavers. Meanwhile, the molded base material <NUM> in each paver <NUM> supports the respective PV panel <NUM> to prevent any bending forces in the panel which might damage the panel structure. Base material <NUM> also functions to transfer any forces applied to the light transmissive load bearing surface <NUM> of the paver to the material making up the PV panel supporting bed <NUM> below. Water may be introduced into the granular material making up the PV panel supporting bed <NUM>, and this introduced water together with the evaporation of that water helps moderate the temperature of pavers <NUM> and PV panels <NUM> incorporated in the pavers. Aside from the water which may be introduced into PV panel supporting bed <NUM>, the thermal mass of the bed <NUM> and subgrade <NUM> in which it is formed also helps moderate temperature swings in PV panels <NUM> due to incident sunlight and atmospheric conditions.

<FIG> shows an alternative landscape paver <NUM> which may be used in installations in which the PV panel is not incorporated in the pavers, but is installed separately from the pavers. Paver <NUM> includes a paver load receiving surface or top surface <NUM>, a paver bottom surface (the edge of which is indicated at <NUM>), and a paver lateral surface <NUM>. In this case the paver lateral surface <NUM> comprises the four lateral sides of the rectangular box shape formed by the paver. The paver body defined between the paver load receiving surface <NUM>, paver bottom surface <NUM>, and paver lateral surface <NUM> is light transmissive so that at least some light incident on the paver load receiving surface <NUM> may travel through the paver body and escape from the paver body through paver bottom surface <NUM>. Paver <NUM> also includes at least one reduced light transmissivity layer extending transverse to a direction from paver load receiving surface <NUM> to paver bottom surface <NUM>. The reduced light transmissivity layer in paver <NUM> includes a light transmissive material in which is included low-light-transmissivity granular material as described above in connection with <FIG> and <FIG>.

In the example paver <NUM> shown in <FIG>, the paver body includes an upper assembly <NUM> and a lower assembly <NUM>. Upper assembly <NUM> in this example is made up of a single layer <NUM> comprising the reduced light transmissivity layer of the paver, and a main layer <NUM> of light transmissive material. Lower assembly <NUM> in paver <NUM> includes a layer <NUM> of light transmissive elastomer material. As will be described below in connection with an installation in which paver <NUM> is used, this light transmissive elastomer is placed facing and perhaps directly in contact with the upwardly facing surface of the PV panel.

While example paver <NUM> includes three layers of material, layers <NUM>, <NUM>, and <NUM>, it will be appreciated that a light transmissive paver in accordance with the aspects of the invention may include more than three layers. Also, it is possible that a bottom elastomer layer may be omitted from the paver and instead applied in an installation as a separate layer of material. In this case a light transmissive paver may include only the reduced light transmissivity layer and one additional layer, or even a single layer of material incorporating low-light-transmissivity granular material. The various layers of material included in the upper assembly <NUM> of paver <NUM> may include any of the light transmissive materials described above in connection with the composite pavers shown in <FIG> and <FIG>. The low-light-transmissivity granular material may also comprise any of the materials described above in connection with the composite pavers.

<FIG> shows an example of a PV panel structure which may be used together with light transmissive pavers such as paver <NUM> to produce a PV panel installation. The illustrated PV panel structure includes a PV panel <NUM> having a panel first surface <NUM> to which light may be directed to produce the desired photovoltaic effect. PV panel <NUM> in this example is mounted in a rigid frame <NUM> which extends around the entire peripheral edge of PV panel <NUM>. Frame <NUM> may have a channel structure similar to that shown in <FIG> and <FIG> for capturing the peripheral edge of PV panel <NUM>. Frame <NUM> also includes a frame member which may be similar to frame member <NUM> shown in <FIG> or a tube structure having frame members similar to frame members <NUM> and <NUM> shown in <FIG>.

<FIG> shows a PV panel installation <NUM> employing pavers <NUM> shown in <FIG> and the PV panel structure shown in <FIG>. Installation <NUM> includes a PV panel supporting bed <NUM> of granular material formed on a subgrade <NUM> similar to the PV panel supporting bed <NUM> shown in the installation of <FIG>. However, in installation <NUM> each PV panel structure including PV panel <NUM> and frame <NUM> is set directly in the PV panel supporting bed <NUM>. That is, PV panels <NUM> are positioned on panel supporting bed <NUM> with panel first surface <NUM> facing upwardly and the panel second surface <NUM> (shown in <FIG>) facing the granular material forming the PV panel supporting bed. Since this example includes frame <NUM> with each PV panel <NUM>, the frame protrudes into the material of PV panel supporting bed <NUM> in position to stabilize the PV panel from lateral movement. PV panels <NUM> in this installation are connected in series via connectors <NUM> similarly to the arrangement shown in <FIG>, although alternative installations may connect the panels differently as described above in connection with the installation shown in <FIG> together with additional circuitry known in the field of PV power generation.

The light transmissive paver <NUM> in this installation is placed with the bottom surface <NUM> formed by elastomer material <NUM> facing the upwardly facing panel first surface <NUM> while the panel second surface <NUM> is supported by the granular material making up the PV panel supporting bed <NUM>. This support from PV panel supporting bed <NUM> below prevents the relatively fragile PV panel <NUM> from bending significantly under loads which may be placed on the top surface of the installation comprising the load receiving surfaces <NUM> of pavers <NUM>.

The example installation <NUM> of <FIG> includes conduits <NUM> similar to those described above in connection with the insulation shown in <FIG>. However other implementations including separately installed pavers and PV panels may omit the conduits and rely on the temperature moderating effect of subgrade <NUM> and PV panel supporting bed <NUM> to moderate the temperatures of the PV panels and thus improve the performance and reliability of the panels.

<FIG> shows a small portion of another installation <NUM> similar to that shown in <FIG>. The view of <FIG> shows that installation <NUM> includes a framed PV panel <NUM> similar panel <NUM> and frame <NUM> in <FIG>, supported on a PV panel support bed <NUM> corresponding to bed <NUM> in <FIG>. Installation <NUM> further includes light transmissive pavers <NUM> above PV panel <NUM>. However, installation <NUM> shown in <FIG> relies on a separate sheet <NUM> of light transmissive elastomer between the upwardly facing surface of PV panel <NUM> and the bottom surface <NUM> of the light transmissive pavers <NUM> placed over the PV panels in the installation. This is in contrast to the arrangement shown in <FIG> using pavers such as those shown in <FIG> which incorporate an elastomer layer as the bottom layer of the paver itself. Yet other implementations may include both an elastomer layer at the bottom of the pavers as in <FIG> and <FIG>, and a separate sheet of elastomer material such as sheet <NUM> in <FIG> that extends over the upwardly facing first panel surface in position to receive the light transmissive pavers.

The PV panel installation shown schematically in <FIG> includes two light-transmissive landscape pavers <NUM> located on top of a PV panel <NUM>. PV panel <NUM> is positioned in landscape ground <NUM> set on top of a PV panel supporting bed comprising a bed of sand <NUM>. An optional layer of landscape fabric <NUM> is located between the PV panel lower surface and the upper surface of sand bed <NUM>. Sand bed <NUM> may contain a series of low volume drip lines <NUM> similar to drip irrigation lines to emit water to sand bed <NUM> in a controlled manner for cooling of PV panel <NUM>, and any associated electronics, such as batteries or micro-inverters <NUM>.

Light transmissive landscape pavers <NUM> in this example embodiment include a glass container <NUM> with an optical, highly light-transmissive coating <NUM> on the upper surface, contained within or below the glass container <NUM> upper surface <NUM>. Within glass container <NUM> is a water clear to clear polyurethane rubber <NUM> which substantially fills the glass container and extends down to the upper surface of PV panel <NUM>. There may be a grout fill material <NUM> which is in between adjacent light-transmissive landscape pavers <NUM>. Sun rays <NUM> pass through the atmosphere <NUM> above pavers <NUM>, through the light transmissive landscape pavers <NUM>, and strike the PV panel <NUM>, allowing solar electric energy to be produced from an aesthetically pleasing landscape paver installation such as a walkway or patio.

The installations according to the preferred embodiment locate conventional PV panels just below the ground, preferably in a sand base such that the sand material butts up to the bottom side surface of the PV panel back sheet or back glass, providing compressive support to the PV panel. The PV panels in the array may be connected together in a typical fashion of any convention multi-panel solar array. All of the necessary electrical connections can be implanted in the sand base beneath the solar modules and waterproofed with conventionally available waterproof connectors. If desired, a water permeable landscape fabric can be installed between the sand layer and the solar panel modules. Additional cooling of the panels can be attained by intermittently running low volume irrigation drip lines installed within the sand base to keep the sand base moist and provide cooling through the latent heat of evaporation as water evaporates from the sand base.

Once the base of sand, optional landscape fabric and irrigation drip tubing is established and the PV panels are laid on top and connected up, the light-transmissive landscape pavers can be laid down over the modules to form the upper patio, walkway or drive surface. The light permeable landscape pavers can be laid in any pattern and extend out past the area of the solar panel modules to create a landscape feature independent of the geometry of the solar array beneath it. In areas of landscape feature where there are no solar modules below the light permeable landscape pavers can be directly laid on a sand base with water permeable landscape fabric on it.

The light permeable landscape pavers can be designed and fit tightly so that no filling grout material is needed between the pavers or they can have an appropriate grout material filled in between the pavers.

The schematic representation of <FIG> shows a composite light-transmissive paver <NUM> with integrally molded concrete back <NUM>, a PV panel <NUM>, and a clear resin or polymer cover material <NUM> providing a top surface <NUM> for the paver. Composite paver <NUM> is placed on sand or the ground surface <NUM> such that it can function as a landscape paver paved patio, walkway or path and an element of a functioning PV panel array.

The integrally molded composite light-transmissive landscape paver may be installed by placing the unit over a sand base like a conventional paver, connecting the leads from the PV panels embedded in the composite light-transmissive landscape pavers, and routing the connections to a string inverter and/or appropriate electrical or panel connections. The electrical inverter could also be located on the back of the PV module and embedded in the concrete on the backside of the composite unit paver.

As used herein, whether in the above description or the following claims, the terms "comprising," "including," "carrying," "having," "containing," "involving," and the like are to be understood to be open-ended, that is, to mean including but not limited to. Also, it should be understood that the terms "about," "substantially," and like terms used herein when referring to a dimension or characteristic of a component indicate that the described dimension/characteristic is not a strict boundary or parameter and does not exclude variations therefrom that are functionally similar. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.

Any use of ordinal terms such as "first," "second," "third," etc., in the following claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another, or the temporal order in which acts of a method are performed. Rather, unless specifically stated otherwise, such ordinal terms are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term).

The term "each" may be used in the following claims for convenience in describing characteristics or features of multiple elements, and any such use of the term "each" is in the inclusive sense unless specifically stated otherwise. For example, if a claim defines two or more elements as "each" having a characteristic or feature, the use of the term "each" is not intended to exclude from the claim scope a situation having a third one of the elements which does not have the defined characteristic or feature.

Claim 1:
A landscape paver including
(a) a PV panel (<NUM>; <NUM>) having a panel first surface (<NUM>) and a panel second surface (<NUM>) with the panel first surface (<NUM>) and the panel second surface (<NUM>) bounded by a panel peripheral edge (<NUM>), the PV panel (<NUM>; <NUM>) being operable to provide electrical power at a panel output terminal (<NUM>, <NUM>; <NUM>, <NUM>) in response to operating light incident on the panel first surface (<NUM>); and
(b) a rigid frame (<NUM>; <NUM>) extending along the panel peripheral edge (<NUM>) and having a frame inside surface (<NUM>: <NUM>) and a frame outside surface (<NUM>; <NUM>),
characterized in that:
(c) the frame inside surface (<NUM>; <NUM>) together with the panel second surface (<NUM>) define a base volume and the frame outside surface (<NUM>; <NUM>) faces away from the base volume;
(d) a molded base material (<NUM>; <NUM>) is located in the base volume, the molded base material (<NUM>; <NUM>) including a base material backing surface and a base material lateral surface, the base material backing surface being molded against at least a portion of the panel second surface (<NUM>) and the base material lateral surface being molded against at least a portion of the frame inside surface (<NUM>); and
(e) a paver cover material (<NUM>; <NUM>) extends over the panel first surface (<NUM>), the paver cover material (<NUM>; <NUM>) being light-transmissive at least in portions extending over one or more areas of the panel first surface (<NUM>).