CLAIM OF PRIORITY

This application claims priority from the following United States Provisional Applications, each of which is hereby incorporated by reference:

(1) Photovoltaic Panel Having A Keying Feature

Thereon, Application S.N. 61/226,838, filed 20 July 2009 (CL-4770) ;

(2) Solar Array Incorporating Photovoltaic Panels Having Keying Features Thereon, Application S.N.

61/226,843, filed 20 July 2009 (CL-4771);

(3) Solar Array Incorporating A Photovoltaic Panel and A Framework Element Each Having Keying Features Thereon, Application S.N. 61/226,847, filed 20 July 2009 (CL-4772);

(4) Method For Installing A Solar Array Incorporating Photovoltaic Panels Having Keying Features Thereon,

Application S.N. 61/226,853, filed 20 July 2009 (CL-4773) ; and

(5) Method For Installing A Solar Array Incorporating A Photovoltaic Panel and A Framework Element, Application S.N. 61/226,861, filed 20 July 2009 (CL-4774).

CROSS REFERENCE TO RELATED APPLICATIONS

Subject matter disclosed herein is disclosed and claimed in the following copending applications, all filed contemporaneously herewith and all assigned to the assignee of the present invention: Solar Array Incorporating Photovoltaic Panels Having Keying Features Thereon And Method For Installing The Same (Cognate CL-4771 & 4773) ; and

Solar Array Incorporating A Photovoltaic Panel and A Framework Element Each Having Keying Features Thereon And Method For Installing The Same (Cognate CL-4772 & 4774) .

BACKGROUND OF THE INVENTION

Field of the Invention This invention relates to a photovoltaic panel that has keying features disposed thereon, to a photovoltaic array formed from a plurality of such panels, to an array formed from at least one such panel and a framework element, and to methods for forming a photovoltaic array.

Description of the Art The potential of solar energy as a clean, renewable energy source is well documented. However, a substantial impediment to more widespread use of solar energy, especially in residential applications, is the significant initial cost of installation of an array of photovoltaic panels.

Each photovoltaic panel has several distinctive features that fall into a variety of categories. Some of these distinctive features (e.g., identification of the panel's edges or surfaces) may pertain to the physical structure of the panel itself. Other distinctive features may relate to aspects regarding the operability of the panel. The number of electrodes whereby panels may be interconnected, the polarity of the electrode at each point, and the location of connections of a certain

polarity with respect to other structural features of the panel are some examples of this category of distinctive feature. Other distinctive features may relate to the aesthetics of the panel (e.g., the colors reflected from various portions of the panel at given times) .

It is often important when installing photovoltaic panels in an array that selected distinctive features on the panels in the array be arranged in accordance with some predetermined pattern. The predetermined pattern may take into account the relationship between and among the panels in the array, as well as the relationship between and among the panels and any framework elements for supporting the array.

Each photovoltaic panel includes electrical connectors on the panel's electrodes, typically in the form of pigtails. Although these connectors may themselves serve as keying features when assembling an array, pig-tailed electrical connectors serve only to insure proper panel-to- panel electrical arrangement. Pig-tailed electrical connectors cannot be relied upon to insure that desired orientation of other distinctive features on the panels are arranged in the desired pattern.

Other forms of connectors for electrodes are

available, such as the connectors used in the Andalay

System available from Akeena Solar, Inc., Los Gatos,

California. This form of connector incorporates a keying function with the connector. In view of the foregoing it is believed to be

advantageous to provide a photovoltaic panel having keying features that facilitate the arrangement of such panels into an array wherein any selected distinctive feature on the panels may be arranged in accordance with a

predetermined pattern. The keying features on the panel should facilitate both the mechanical mounting of the panels to a support surface or to a framework in a

predetermined pattern as well as the electrical

interconnection of the panels in the array in a desired electrical connection pattern.

It is believed to be of further advantage to provide a panel construction that includes keying features which minimizes the training required for installation personnel to properly install an array and minimizes the possibility of incorrect installation of an array.

SUMMARY OF THE INVENTION

In a first aspect the present invention is directed to a photovoltaic panel that has an electrode of a positive electrical polarity and an electrode of a negative

electrical polarity. The panel has at least one

distinctive feature thereon. One of the electrodes on the panel may comprise the distinctive feature although any other structural or an aesthetic aspect of the panel may alternatively or additionally serve as a distinctive feature of the panel.

The panel further comprises at least one keying feature in addition to the electrodes. The keying feature is separate from the electrodes and is located on the panel in a position spaced away from the electrodes. The keying feature is disposed in a predetermined relationship with respect to the distinctive feature of the panel. The panel may also include a second keying feature thereon that is disposed in a predetermined relationship with respect to the distinctive feature of the panel. The second keying feature on the panel is complementary to the first keying feature on the panel.

The first keying feature on the panel is cooperatively associable with a complementary keying feature on another member such that the distinctive feature of the panel occupies a predetermined positional relationship with respect to a distinctive feature on the other member when the panel and the other member are operatively arrayed with respect to each other.

The "other member" may be another panel or a framework element or support surface on which the panels are mounted. The distinctive feature on the other member may be an electrode of a predetermined electrical polarity, an electrical connection point, or a structural or aesthetic feature of the other member.

The presence of at least one keying feature on a first panel and a complementary keying feature on the other member, coupled with the predetermined positional

relationships between the respective keying feature on the panel and other member and the respective distinctive features on the panel and other member, facilitates the installation of such panels into an array that exhibits a desired positional relationship between the distinctive features .

In another aspect the present invention is directed to a photovoltaic array comprising a first panel and a second panel each configured to include a first keying feature and a second complementary keying feature. Alternatively, a photovoltaic array in accordance with this aspect of the invention may include at least a first panel configured to include at least a first keying feature and a framework element or a support surface on which the first panel is mounted. The framework element or a support surface has a keying feature that is complementary to the keying feature on the panel. The framework element may also have a distinctive feature, such as an electrical connection point, thereon.

In yet another aspect the present invention is

directed to a method for forming a photovoltaic array comprising a first panel and another member, wherein the other member may comprise a second panel or a framework element or support surface on which the first panel is mounted. The method includes the steps of:

bringing the first and the other member into proximity with each other such that a first keying feature on the first panel is cooperatively associated with a

complementary keying feature on the other member; and

joining the first panel and the other member to each other such that the distinctive feature on the first panel occupies a predetermined positional relationship with respect to a distinctive feature on the other member.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detailed description taken in connection with the accompanying Figures, which form a part of this application and in which:

Figure 1 is a stylized representation of a

photovoltaic panel in accordance with the present

invention, with a portion of the frame of the panel removed for clarity and with a portion of the module broken away to illustrate the laminated structure of the module, the panel being illustrated as proximal to another member;

Figure 2 illustrates an arrangement wherein the locations of the complementary keying features disposed on a panel or on another member, as the case may be, are adjustably selectable.

DETAILED DESCRIPTION OF THE INVENTION

Throughout the following detailed description similar reference numerals refer to similar elements in all figures of the drawings.

Figure 1 is a stylized representation of a

photovoltaic panel generally indicated by the reference character 10 in accordance with the present invention. The panel 10 comprises a photovoltaic module 12 that is surrounded by a frame generally indicated by the reference character 14.

The module 12 is a four-sided, usually rectangular, laminated structure having opposed pairs of longer side edges and respectively adjacent shorter side edges. The module can be implemented in square form, if desired.

As seen in the broken-away portion of Figure 1 the photovoltaic module 12 includes a photovoltaic layer 12P having one or more electrically interconnected photovoltaic cells formed therein. The photovoltaic layer 12P is usually sandwiched between a bottom support sheet 12B and a transparent top covering sheet 12T. The outer surface of the bottom sheet 12B defines the lower surface of the module 12 while the outer surface of the transparent covering sheet 12T defines a generally planar radiation collection surface 12R for the module. Each photovoltaic cell is operative to generate an electric current in response to incident radiation falling upon the radiation collection surface 12R.

The frame 14 is a four-sided structure that

corresponds in peripheral shape to the shape of the module 12. For use with a rectangular module the frame 14

exhibits opposed pairs of longer side edges 14L ¹ , 14L ² and respectively adjacent shorter side edges 14S ¹ , 14S ² . The frame 14 may be a modularized structure implemented by interconnecting a plurality of frame pieces into the desired peripheral form. Alternatively the frame may be implemented using frame bars to define the opposed sides of the frame with adjacent frame bars being connected at their ends or in any other convenient fashion. A rail frame may also be used.

Any suitable photovoltaic module 12 may be used in the panel 10. In a typical instance the string of

interconnected photovoltaic cells within the module 12 terminates in electrical connection tabs. The tabs are themselves connected to any convenient form of electrode by which the cells within the module may be connected electrically to points outside the module. As will be discussed it should be appreciated that the tabs need not necessarily emanate from the same major surface (or from the same edge surface) of the module. Moreover, the tabs need not emanate from the desired surface of the module in the same vicinity.

In the usual case the tabs emanate from the bottom surface 12B of the module 12. In one typical form of construction the connection tabs project from slots in the module's bottom surface located along one of its shorter side edges. The tabs project into a junction box 16 that is itself attached to the bottom surface 12B of the module. Within the junction box 16 one tab is connected to a first electrode 18E _P that has a positive electrical polarity. The other connection tab is connected to a second electrode 18E _N that has a negative electrical polarity. It should be appreciated that the electrodes may be provided with any of various forms of electrical connector, such as pig-tailed connectors 20 shown extending from the module 12.

It should be appreciated that the tabs need not necessarily emanate from the same vicinity of the same major or edge surface of the module. Thus, for example, Figure 1 alternatively illustrates that the connection tabs may emanate from the bottom surface of the module along adjacent opposed side edges. As suggested in the drawing, the alternatively located connection tabs may be connected to disc-like electrodes 22 that are mounted to the frame 14.

The photovoltaic panel 10 may exhibit any of several distinctive features that fall into a variety of

categories. As used in this application, including the claims, the term "distinctive feature" is intended to be broadly construed. For purposes of discussion of the present invention the presence of a distinctive feature on the panel 10 is generically indicated by a diamond shape denoted by the reference character "D" on the drawing.

However, it is expressly noted that the location of the distinctive feature D on the drawing is not to be construed as limiting.

One category of distinctive features may pertain to the physical structure of the panel itself, e.g.,

identification of the edge(s) and/or surface (s) (or a portion of the same) of either the module and/or the frame.

Another category of distinctive features may relate to aspects regarding the operability of the panel. Exemplary of this category would be the number of the electrodes or electrical connection points whereby panels may be

interconnected, the polarity of the electrical connector at each point, the form of the connector at each point, and the location of connections of a certain polarity with respect to other structural features of the panel.

Still other distinctive features may relate to the aesthetics of the panel, e.g., the color (s) reflected from various portions of the module and/or frame at given times.

In accordance with the present invention the panel further comprises at least one, but preferably a pair of complementary keying features, indicated generally by the reference character 26 and 28, respectively. As is

apparent from the drawing each keying feature 26, 28 is located on the panel 10 at any convenient location that is spaced away from (i.e., not incorporated with) the

electrodes 18E _N and 18E _N .

Each keying feature 26, 28 is disposed in a

predetermined relationship with respect to the distinctive feature D on the panel. The relationship between the keying feature 26 and the distinctive feature D is

indicated by the reference arrow 30, while the relationship between the keying feature 28 and the distinctive feature D is indicated by the reference arrow 32. The keying

features 26, 28 are located in positions on the panel that are complementary to each other. In the embodiment shown in Figure 1 the keying feature 26 is illustrated as a notch 26N provided on the frame 14. The keying feature 28 is illustrated as a projection 28P provided in a complementary location on the frame 14. It should be understood that the keying features 26, 28 on the panel 10 may be implemented in any convenient form. The keying features may be implemented as a structural element of the frame of module, or any distinctive surface feature of the panel. A difference in texture and/or color of a portion of the panel is exemplary of a distinctive surface feature .

Figure 1 suggests the presence of another member generally indicated by the reference character M. As will be discussed the other member M may take the form of another panel, a framework element for a framework

supporting an array of panels, or the support surface for the panel (e.g., the roof of a structure) . The other member M has a distinctive feature D and at least one keying feature K disposed thereon. The distinctive feature D on the other member M can be defined by an electrode E or by an electrical connection point on the member. The keying feature K on the other member M is complementary to one of the keying features 26, 28 on the panel 10.

In general, a keying feature 26, 28 on the panel 10 is cooperatively associable with a complementary keying feature K on another member M such that the distinctive feature D on the panel 10 occupies a predetermined

positional relationship with respect to a distinctive feature D on the other member M when the panel 10 and the other member M are operatively arrayed with each other.

For example, it is often desired to install two or more photovoltaic panels into an array wherein selected distinctive features on the panels in the array are

arranged in accordance with some predetermined pattern. In such an instance the other member M will take the form of a panel generally similar to the panel 10. The presence of at least one keying feature 26, 28 on a first panel 10 and a complementary keying feature 28, 26 on the other member (e.g., an adjacent panel) coupled with the predetermined positional relationships between the respective keying feature on the panel and other member and the respective distinctive features on the panel and other member, facilitates installation of such panels into an array that exhibits a desired positional relationship between distinctive features D on the adjacent panels.

It should be noted that adjacent panels in an array need not be identically configured so long as the keying features on the panel 10 and on the panel serving as the other member M have complementary keying features thereon and that the panels include the predetermined positional relationships between the keying features and the

distinctive features.

To install such an array a first panel 10 having a first keying feature 26 thereon is brought into proximity to an adjacent second panel. The keying feature 26 on a first panel 10 is able to be cooperatively associated with the complementary keying feature K disposed in a

complementary position on another panel so that when the panels are operatively arrayed with respect to each other the distinctive feature D on the panel 10 occupies a predetermined positional relationship with respect to the distinctive feature D on the other member (i.e., a second panel) .

The other member M may also be implemented as a framework element of a support framework for a photovoltaic array. The present invention may also be used to position the keying feature on a panel 10 with respect to a

distinctive feature (e.g., an electrical connection point) disposed on such a framework element

As long as one of the keying features on the panel 10 is cooperably associable with the complementary keying feature on the framework element the distinctive feature on the panel (e.g., the electrodes on the panel) will occupy a predetermined positional relationship with respect to the connection point on the framework element when the panel is mounted to the framework element.

To install a panel 10 to the support element the panel is brought into proximity with the support element so that the keying feature 26 on a panel 10 is able to be

cooperatively associated with the complementary keying feature disposed on the support element. When the panel 10 and the support element are operatively joined to each other the distinctive feature D on the panel 10 occupies a predetermined positional relationship with respect to the distinctive feature D on the support element.

The location of one and/or both of the keying features 26, 28 on a panel 10 and on the other member M is

adjustably selectable. Figure 2 illustrates two generally similar (but not identical) adjacent panels 10, 10'. The keying feature on the panel 10 takes the form of a peg 36 that may be received in any of a plurality of openings 38 disposed along the frame 14 of that panel. The

complementary keying feature on the panel 10' takes the form of a flange 42 having a keyway 44 sized to accept the peg. The flange 42 is positionable in any of a plurality of openings 46 provided in the panel 10' .

Those skilled in the art, having the benefit of the teachings of the present invention as hereinabove set forth may effect numerous modifications thereto. Such

modifications are to be construed as lying within the contemplation of the present invention as defined by the appended claims.