CN102804402A - Solar shingle system - Google Patents

Abstract

The present invention consists of asphalt roof shingles integrated with thin film solar cells that are easy to install and can be varied for each specific application. The system of the present invention comprises a standard asphalt roof shingle with integrated thin film solar cells connected to two electrodes disposed on opposite sides of the shingle. The shingles form the dimensions of standard asphalt shingles. The roof nails used to mount the shingles to the roof physically connect the shingles to the roof and also establish electrical connections between the electrodes of the individual shingles, creating a unified electrical circuit between the fixed solar shingles.

Description

Solar Shingle Systems

Cross References to Related Applications

This application claims priority to U.S. Provisional Patent Application U.S. 61/220,539, filed June 25, 2009, and U.S. Utility Model Application U.S. 12/823,006, filed June 24, 2010, the disclosures of which are incorporated herein by reference Applying.

technical field

The present invention relates generally to photovoltaic roofing systems, and more particularly to roofing materials capable of generating electricity. More particularly, the present invention relates to a roof shingle structure and wiring system that is compatible with conventional shingles and capable of generating electricity.

Background technique

Description of related fields

Environmental pollution and energy shortage are current global concerns. Increasing interest is focused on solar energy, which promises an unlimited source of clean energy. Solar power is clean and an affordable solution to growing energy demands. Solar energy is a renewable energy resource and has gained worldwide popularity due to the awareness of the limitations of fossil fuels and the safety of nuclear fuels. The part that can now be done is converting light energy into electricity. Such "photovoltaic cells" generally consist of semiconductor-type materials such as doped silicon in monocrystalline, polycrystalline or amorphous form.

The energy generated by a photovoltaic device is proportional to the incidence of light on it, requiring a considerable collection area if relatively large amounts of energy are generated. The roof and upper areas of the building structure are well lit, but are generally not converted to productive use. Placing solar thermal and photovoltaic collectors on top of buildings has been known for some time. Roofs mounted with photovoltaic devices, for example, are shown in U.S. Patents U.S. 5,092,939, 5,232,518 and 4,189,881. These concrete photovoltaic roof structures are of the plank and joint type.

These photovoltaic cells for rooftop use are becoming extremely common and an important source of electricity, especially improving the performance of the device. Over the past 15 years, demand for photovoltaic (PV) solar energy has grown by at least 25% per year. Worldwide photovoltaic installations grew from 1086MW installed in previous years (representing a 34% annual increase) to 1460MW (megawatts) in 2005, compared with 21MW in 1985.

Photovoltaic (PV) materials are now well known and commercially available in a variety of forms. Recent advances in photovoltaic processes have enabled the large-scale fabrication of low-cost, light-component, thin-film photovoltaic devices. Large scale thin film silicon and/or germanium alloy materials with balanced electrical and optical properties and in many ways superior to their single crystal counterparts can now be fabricated. These alloys can be deposited at high speed and economically over relatively large areas and in a variety of device setups, so they can be readily used in the fabrication of low-cost, large-area photovoltaic devices. U.S. Patents U.S. 4,226,898 and 4,217,364 both disclose specific thin film alloys that can be used in the manufacture of photovoltaic devices of the type used in the present invention. It should be understood, however, that the present invention is not limited to any particular type of photovoltaic material and may be used with a variety of semiconductor materials including crystalline, polycrystalline, microcrystalline and amorphous materials.

Developments in the field of solar energy have focused on solar modules that are fixed to existing roofs. The roof provides direct exposure of light radiation to the structural support of the solar cells and photovoltaic devices. Despite growth, the widespread use of conventional roof-mounted solar modules has been limited by installation difficulty and cost, aesthetic appearance and especially their low conversion efficiency.

Many traditional roof-mounted solar modules are largely constructed of glass seals, designed to protect the fragile silicon solar cells. These modules are complex systems comprising discrete mechanical and electrical interconnections and then installed into existing roofs, requiring significant installation time and skill. Additionally, since the existing modules do not provide roof weather protection, the homeowner bears the cost of materials and labor for the modules and the protective roofing material they are installed on. The various modules also detract from the aesthetics of residential and commercial buildings, resulting in limited use. For example, in FIG. 1 , a conventional solar panel power generation system 100 generally includes one or more rigid solar panels 106 , 108 mounted on a roof 104 of a residential structure 102 . In addition to being expensive to install and maintain, solar panels 106 , 108 have the potential to detract from the aesthetics of residential structure 102 .

Wood shingle roofs are popular in many situations, typically for residential structures, and in those cases quite complex roof geometry problems are often encountered. For example, asphalt shingles account for nearly two-thirds of the U.S. residential roofing market. In typical shingle construction, the roofing material is supplied in rolls or in pre-sliced forms that are then placed in an overlapping arrangement. Sometimes the roof is extruded with relatively thick tiles, which may be flat or curved. It should be noted that integrated photovoltaic energy generation with a shingled roof structure is required.

Photovoltaic roof elements are often difficult to install as they not only need to be physically connected to the roof in a manner that provides weather protection, but also need to be electrically interconnected to elements connected to the larger photovoltaic generation system such as inverters, batteries and meters wiring system. These installations often require circuit specialists to perform the electrical interconnection, which is difficult in proportion to the time it takes to physically install the photovoltaic roof elements. Also, relatively large voltage differences (eg, 100-600V) are generated in many photovoltaic rooftop systems. As such, electrical interconnections need to be protected from weather to avoid arcing and short circuits.

U.S. Patent U.S. 4,040,867 describes a photovoltaic shingle structure comprising a variety of individual shingle components, each of which has a number of electrically interconnected single crystal photovoltaic devices thereon. To obtain high energy from such devices, a single shingle must be large or several shingles need to be electrically interconnected. The first method presents problems with wind loads, the second method results in a structure requiring extensive weatherproof electrical interconnections; moreover, the spread of moisture between adjacent shingles due to capillarity can lead to leaks. Another photovoltaic shingle construction is described in U.S. Patent U.S. 4,321,416. U.S. Patent U.S. 3,769,091 also describes another photovoltaic rooftop system comprising a plurality of individual silicon devices mounted in overlapping relationship.

More recently, U.S. Patents U.S. 5,575,861 and U.S. 5,437,735 disclose a photovoltaic roofing system comprising long strips of roofing material with overlapping portions, and from there multiple protrusions separated by finely grained inactive areas. Each protrusion includes a photovoltaic generating device secured thereto. A sealing layer covers the top surface of each strip and wraps along the exposed and sides. The photovoltaic devices are electrically interconnected, and each photovoltaic shingle component includes small electrical terminals for transferring energy from the photovoltaic devices. In use, the shingle units are secured to the roof such that the protruding portion of one row of shingles covers the overlapping portion of an adjacent row. However, each electrical interconnect passes through the roof to a point on the inside of the building or on the roof.

The prior art fails to provide acceptable shingle-type photovoltaic roof systems. While prior art manufacturers have produced solutions that are more aesthetically pleasing and less obstructive, the system is not very price competitive due to installation difficulty and poor overall surface efficiency. Lower photovoltaic efficiency levels are associated with higher photovoltaic system costs because larger module areas are required for a given energy demand. Prior art devices are often thick, weak or they are not geometrically compatible with standard structural processes. As such, prior art photovoltaic shingle structures require specific installation techniques and trained personnel, which increases their cost and limits their use. Also, these structures are not easily integrated into conventionally constructed roofs. In addition, prior art photovoltaic roof structures present aesthetic problems because the devices often have different colors and geometries, making them very obvious when they are installed.

Clearly, there is a need for a photovoltaic roofing material that resembles conventional roofing materials as much as possible. The photovoltaic portion of the roofing material should be self-contained with a large angle and easy to install using conventional techniques. It should also be relatively light in weight, resistant to wind loads and stable in adverse atmospheric conditions.

The present invention, described in further detail below, provides a roofing material including photovoltaic technology incorporated into conventional structural shingle stock. The roofing material of the present invention is easy to install and efficiently converts light to electricity, and can be combined with standard, non-photovoltaic shingles to cover any desired roof section. The special structure of the present invention enables efficient use of roof space for generating electricity and is inconspicuous in use. These and other advantages of the present invention will be more apparent from the following figures, discussions and descriptions.

Contents of the invention

The present invention overcomes many of the disadvantages of prior art photovoltaic roof systems by disclosing a roof shingle with integrated thin film solar cells that is easy to install and can be modified for each specific application. While solar energy is the answer, the key to execution is whether it is easily "taken" by users. As mentioned earlier, conventional solar panels are often considered bulky, difficult to install and unsightly to install on their house by the average user. Therefore, there is a need for a solar energy solution that is more acceptable to users.

The system of the present invention comprises standard pitch roof tiles with multiple integrated thin film solar cells. The shingles are formed to have the dimensions of standard asphalt shingles. Roof nails used to attach shingles to the roof physically connect the shingles to the roof and also create electrical interconnections between the shingles to form a unified circuit.

In preferred embodiments, the solar shingles of the present invention incorporate flexible photovoltaic cells that are visible when properly installed on a roof. Two wires are connected to the photovoltaic cells, but are buried in the shingle layer. Since the shingles overlap the roof, roof nails are used to attach the shingles to the shingle. In one embodiment, the nails are used as electrical conductors to travel between the shingles and through the electrode leads. Electrode wires are the conductive layer in the shingle. The positive (+) electrode lead on the first shingle is connected to the negative (-) electrode lead on the two following shingles. The shingles need to be able to withstand harsh conditions. In one embodiment, the exposed PV cells are covered with a translucent material to absorb minor impacts and shield them from rain.

The system of the present invention also includes a battery system, which is typically located in the house/garage for storing electrical energy. The battery is preferably lead phosphate. The system also includes a positive pole and a negative plane is established by the upper or lower electrode strips. The use of flexible or thin film PV is less efficient than crystalline monolithic PV, but the shingles of the present invention are easily installed on a wider variety of roofline structures. And, the solar shingle design allows for installation by standard roofing crews.

Residential generation is often encouraged by local utilities. The solar shingle system of the present invention produces the most energy during the day and has the greatest consumption in the energy grid. Solar shingles should meet basic house energy needs such as refrigerators and emergency lights when an electrical "outage" occurs.

Description of drawings

A more complete understanding of the methods and apparatus of the present invention can be obtained by referring to the following detailed description when taken in conjunction with the accompanying drawings, in which:

Figure 1 is an equivalent perspective view of a typical prior art power generation system with a rigid photovoltaic solar panel array;

Figure 2a is a top or exterior exposure view of a solar shingle embodiment of the present invention;

Figure 2b is a bottom or bottom view of the embodiment of the solar shingle of the present invention shown in Figure 2a;

Figure 3 is a cross-sectional view of the solar shingle embodiment of the present invention shown in Figure 2a;

Figure 4 is a top view of a plurality of solar shingles of the present invention physically or electrically connected to a photovoltaic array;

Figure 5 is a cross-sectional view of a plurality of solar shingles of the present invention shown in Figure 4;

Figures 6a-6d are equivalent perspective views depicting various stages of construction of a photovoltaic system using the solar shingles of the present invention.

The use of the same numerals in the several figures herein indicates the same or similar parts. Furthermore, when the terms "top", "bottom", "first", "second", "upper", "lower", "height", "width", "length", "end", "side", When "horizontal", "vertical" and similar terms are used herein, it should be understood that these terms refer only to the structures shown in the drawings and are used only for ease of description of the invention.

All the drawings drawn are merely to facilitate the explanation of the basic teaching of the present invention; after studying and understanding the following teachings of the present invention, the range of numbers, positions, relationships and dimensions of the parts forming the preferred embodiment in the drawings can be obtained explained or within the scope of skill in the art. Also, the exact dimensions and proportions of dimensions consistent with specific force, weight, strength and similar requirements will be the same as those in the art upon study and understanding of the following teachings of the present invention.

Detailed ways

Detailed description of the invention

Referring to Figures 2a-3, an embodiment 200 of a solar shingle of the present invention comprising a standard asphalt roof shingle with integrated thin film solar cells is depicted. Asphalt shingles generally consist of four basic materials:

Fiberglass or cellulose support;

asphalt cement;

sand-like stones called aggregates; and

Mineral fillers or stabilizers including limestone, dolomite and silica.

As shown in FIG. 2 a , the outside or exterior facing side 202 of each solar shingle 200 includes a plurality of thin film solar cells 206 formed or affixed thereon and electrically connected to the outer side of the solar shingle 200 . Or the upper electrical connection body or the electrode wire 204 on the upper part of the outer side 202 . Discrete electrical conduits 205 , such as conductive leads, are used to electrically connect the upper electrode 204 to the plurality of thin film solar cells 206 .

As shown in FIG. 2 b , the bottom side or bottom-facing side 203 of each solar shingle 200 includes a lower electrical connector or electrode formed on or secured to the middle portion of the bottom or bottom-facing side 203 of the solar shingle 200 . Wire 208. Discrete electrical conduits 207 , such as conductive leads, are used to electrically connect the lower electrode 208 to the plurality of thin film solar cells 206 . The bottom side or bottom facing side 203 of each solar shingle 200 may also include adhering the bottom side or bottom facing side 203 of each solar shingle 200 to the outside or outer facing side adjacent or adjacent to the solar shingle. 202 of adhesive strip 209 . It should be understood that the upper electrode 204 can be either the cathode or the anode as long as the lower electrode 208 is the other pole. And as long as this setting is consistent across all shingles of a particular system.

Referring now to FIG. 3, note that the upper 204 and lower 208 electrodes on each shingle 200 are isolated and insulated from each other. Furthermore, the electrical conduits 205, 207 are also isolated and insulated from each other. Asphalt material for shingles can be used as a non-conductive material. However, it is observed that the upper 204 and lower 208 electrodes are disposed on each shingle 200 so that they align with electrodes on another solar shingle when properly positioned above or below the other shingle. For example, as shown in FIGS. 4 and 5, when the second shingle 200b is properly arranged on the first shingle 200a in an overlapping configuration, the upper electrode 204a of the first shingle 200a is configured to align with the electrode on the second shingle 200b. The lower electrodes 208b are aligned.

The solar shingle 200 of the present invention is designed to be installed in a manner similar to standard asphalt shingle installations. A string of nails 212 is used to secure one shingle to the two shingles located below it. In one embodiment, nails 212 are simply used to ensure that the respective upper and lower electrodes are mechanically connected to each other and to the roof 304 below.

In another embodiment, the nails 212 may be partially conductive to allow the transfer of electrical current from the upper electrode of one shingle to the respective lower electrode of an adjacent shingle. The use of partially conductive nails allows the outer surface of the electrode to be coated or sealed in a non-conductive material. The nails described are partially conductive because they only partially conduct electricity from the lower electrode of one shingle to the upper electrode of the other shingle and vice versa, but do not allow the circuit to ground into the roof surface 304 below.

With reference to the drawings, and in particular Figures 6a-6d, the method of installation of the system is described. A typical system 300 is secured to a structure 302 having a roof 304, as shown in FIG. 6a. System 300 includes a lower electrode strip 310 secured to the bottom edge of roof surface 304 . As depicted in the figure, the lower electrode strip 310 is connected to a terminal of a collection device 312, such as a battery, by an electrical connection 311, such as an insulated lead. The collection device 312 is also connected to the upper electrode strip 330 by a second electrical connection 314 , such as an insulated lead wire. It should be understood that harvesting device 314 of system 300 may alternatively include a conventional electrical converter (not shown) or a device that transfers the generated electrical current back into an electrical grid (yet not shown).

As shown in Figure 6b, the first row of solar shingles 320 is secured to the roof 304 below by conventional means using nails 212 driven into each shingle (ie 320a, 320b, 320c, 320d, 320e). Each shingle of the first row 320 is positioned such that its lower electrode 208 is positioned above the lower electrode strip 310 . In this way, the lower electrode 208 of each respective shingle is electrically connected to the lower electrode strip 320 as each shingle is secured by the nails 212 to the roof 304 below. When each successive and overlapping row is secured to the roof, the lower electrode of each shingle is positioned over and electrically connected to the upper electrodes of the two underlying shingles. The adhesive strip 209 on the bottom or bottom facing side of each solar shingle also helps to bond and seal the adjoining electrodes against weather.

For example, referring again to FIGS. 4 and 5 , when an overlapping solar shingle 200b is properly mounted on two underlying solar shingles 200a, 200b, the lower electrode 204b of the overlapping solar shingle 200b is disposed between the underlying solar shingles 200a, 200b. 200c on the upper electrodes 204a, 204c so that when secured to each other by nails 212 an electrical connection is made in all three shingles. Practitioners in the field will quickly appreciate that in the form of successive overlapping rows 320, 322, 324, 328 shown in Figure 6c, all of the shingles can be electrically connected to each other to create an electrical circuit that collects the current generated by the photovoltaic cells . Note also that the number of solar shingles used can vary relative to the electrical current required to be generated and the physical constraints of the roof area.

As shown in FIG. 6d , the last row of solar shingles is covered by the upper electrode strip 330 such that the upper electrode 204 of each respective solar shingle in the last row is electrically connected to the upper electrode strip 330 . The upper electrode strip 330 is in turn electrically connected to the battery 312 through a second electrical connection 314 (eg, a lead wire). The upper electrode strip 330 may also include a durable outer layer that allows it to blend into the roofline and protect the roof from rain erosion.

The improved solar shingles and solar shingle systems that have been described herein will now be apparent to those skilled in the art. While the invention has been described in terms of preferred embodiments, it is obvious that other adaptations and modifications can be used without departing from its spirit and scope. For example, all of the components of a shingle can be incorporated into a similar shingle base. The terms and expressions used herein, and terms of description, are not intended to be limiting nor to exclude equivalent variations, but on the contrary, are intended to cover any and all equivalents that may be used without departing from the spirit and scope of the invention .

Claims (20)

1. A solar shingle comprising the combination of: Asphalt shingles with exterior and bottom sides; The exterior includes a plurality of solar cells affixed thereto and a first electrode, wherein the plurality of solar cells is electrically connected to the first electrode; and The bottom side includes a second electrode electrically connected to the plurality of solar cells. 2. The solar shingle of claim 1, wherein said bottom side further comprises an adhesive strip along the length of said shingle. 3. The solar shingle of claim 1, wherein said solar cells comprise flexible thin film photovoltaic materials. 4. The solar shingle of claim 1, wherein a plurality of solar cells are electrically connected to the electrodes by insulated wires embedded in the shingle. 5. The solar shingle of claim 1 , wherein said electrodes are disposed on said shingle such that when a second shingle is disposed on a first shingle in an overlapping manner, a first electrode on a first shingle Align with the second electrode on the second shingle. 6. A solar shingle comprising the combination: Roof shingles having an exterior surface and a bottom surface; said exterior surface includes at least one solar cell and a first electrode affixed thereto, wherein said at least one solar cell is electrically connected to said first electrode; and The bottom surface includes a second electrode electrically connected to at least one solar cell. 7. The solar shingle of claim 6, wherein said bottom surface includes an adhesive strip along the length of said shingle. 8. The solar shingle of claim 6, wherein at least one solar cell is comprised of a flexible thin film photovoltaic material. 9. The solar shingle of claim 6, wherein said at least one solar cell is electrically connected to said electrodes by insulated wires embedded in said shingle. 10. The solar shingle of claim 6, wherein said electrodes are disposed on said shingle such that when a second shingle is disposed on a first shingle in an overlapping manner, a first electrode on a first shingle Align with the second electrode on the second shingle. 11. A power generation system comprising the combination of: an electrical collection device; a first electrode strip electrically connected to said collection means, said first electrode strip being affixed to a roof surface; a second electrode strip electrically connected to the collection device, the second electrode strip secured to the roof surface and spaced apart from the first electrode strip; A plurality of solar shingles disposed in an overlapping manner between the first and second electrode strips, wherein each of the plurality of solar shingles comprises: Roof shingles having an exterior surface and a bottom surface; said exterior surface includes at least one solar cell and a first electrode affixed thereto, wherein said at least one solar cell is electrically connected to said first electrode; and said bottom surface includes a second electrode electrically connected to at least one solar cell; wherein the electrodes are positioned on the shingles such that when a second shingle is positioned in an overlapping manner on the first shingle, the first electrode on the first shingle is aligned with the second electrode on the second shingle ; Wherein, when said plurality of solar shingles are arranged in said overlapping manner, a circuit is formed between said first and second electrode strips. 12. The power generation system of claim 11, wherein said electrical collection device comprises a battery. 13. The power generation system of claim 11, wherein said electrical collection means comprises electrical converter means. 14. A power generation system according to claim 13, wherein said electrical converter means is connected to an electrical grid. 15. The power generation system of claim 11, wherein the bottom surface of each solar shingle includes an adhesive strip along the length of the shingle. 16. The power generation system of claim 11, wherein said at least one solar cell on each solar shingle is comprised of a flexible thin film photovoltaic material. 17. The power generation system of claim 11, wherein said first electrode is electrically connected to said second electrode on a bottom surface of each of said plurality of solar shingles in a first row. 18. The power generation system of claim 17, wherein said second electrode is electrically connected to said first electrode on an exterior surface of each of said plurality of solar shingles in a second row. 19. The power generation system of claim 11, wherein each of said plurality of solar shingles is secured to said roof surface by at least one nail fastener. 20. The power generation system of claim 19, wherein said at least one nail fastener is partially conductive.

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