CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Application No. 62/825,540 filed March 28, 20 f 9, entitled“Floating Solar Tracker,” the contents of which is incorporated herein in its entirety.

FIELD

[0002] The current subject matter is directed to floating solar panel systems with solar photovoltaic (PV) panels secured to floating structures.

BACKGROUND

[0003] Solar PV panels collect light from the sun, which can be converted into electric power. Referred to as dual-glass panels, some PV panels use two glass sheets with photovoltaic materials sandwiched between them. Other PV panels, called framed panels, use a glass sheet with a polymer backing and a frame. PV panels can take other forms as well.

[0004] A mechanical support structure can help to position PV panels properly to maximize sunlight exposure. Some mounting structures, referred to as solar trackers, incorporate a system to move the PV panels to orient them toward the sun as it moves across the sky during the day and through the seasons.

[0005] Land installation of solar PV panels can require large areas of land. Such

installations can be space constrained due to land availability. Large bodies of water such as oceans, lakes, pond, man-made reservoirs, and the like, may not be as space constrained as areas of land. Floating solar panel systems can alleviate space constraints presented by land installations.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. f schematically illustrates an example floating solar tracker.

[0007] FIG. 2 schematically illustrates the example floating solar tracker of FIG. 1 anchored to a surface beneath a body of water.

- f - [0008] FIG. 3 schematically illustrates an example floating solar tracker having reflective plastic material draped between the hollow cylinders of the floating structure.

[0009] FIG. 4 schematically illustrates an example floating solar tracker having liquid stored within the hollow cylinders of the floating structure.

[0010] FIG. 5 schematically illustrates a perspective view of an example floating solar tracker with a sprinkler panel cleaning system.

[0011] FIG. 6 schematically illustrates an example system of multiple floating solar trackers mechanically coupled together and arranged in rows.

SUMMARY

[0012] In one aspect, a floating solar tracker includes a plurality of solar photovoltaic panels, a mechanical structure configured to support the plurality of solar photovoltaic panels, and a floating structure configured to float on a body of water. The mechanical structure is secured to the floating structure.

[0013] In some variations, the floating structure can include a pair of hollow cylinders. The pair of hollow cylinders can each have a positive buoyancy to facilitate floating on the body of water. The pair of hollow cylinders can be configured to facilitate light reflection. The pair of hollow cylinders can be white. The pair of hollow cylinders can include a sealing mechanism configured to prevent hollow cylinders from filling with water. The sealing mechanism can be a seal or a cap.

[0014] In other variations, the mechanical structure can include a central purlin coupled to a backside of the plurality of solar PV panels. The central purlin can include an integrated water pipe configured to facilitate transporting a liquid for cleaning of the plurality of solar PV panels. The pair of hollow cylinders can include the liquid.

[0015] In some variations, the floating solar tracker can include one or more sprinklers coupled to the central purlin. The one or more sprinklers can be configured to spray the liquid onto a surface of the plurality of solar PV panels. [0016] In other variations, (i) a reflective plastic material can be stretched on top of the floating structure having an albedo greater than an albedo of the body of water and (ii) the reflective plastic material can be configured to increase an amount of light reflected to the plurality of solar panels.

[0017] In some variations, the mechanical structure can be secured to the floating structure via one or more anchor bands. Each anchor band can have a diameter larger than that of a perimeter of one of the pair of hollow tubes.

[0018] In other variations, the mechanical structure can include (i) at least two purlins configured to support the plurality of solar PV panels and (ii) a drive shaft configured to rotate the plurality of solar PV panels. The sharp wire can be strung above at least one of (a) the at least two purlins or (b) the draft shaft.

[0019] In another aspect, a floating solar tracker system can include a plurality of floating solar trackers, each floating solar tracker including a plurality of solar photovoltaic panels, a mechanical structure configured to support the plurality of solar photovoltaic panels, and a floating structure configured to float on a body of water. The mechanical structure is secured to the floating structure.

[0020] In some variations, the floating solar tracker can include a slew drive motor coupled to one or more of the plurality of floating solar trackers. The slew drive motor can be configured to rotate the plurality of solar PV panels.

[0021] In other variations, each floating solar tracker can include a drive shaft and the plurality of floating solar trackers can be coupled together via the drive shaft.

[0022] In some variations, the floating solar tracker system can include one or more structural members configured to couple together each floating solar tracker of the plurality of floating solar trackers.

DETAILED DESCRIPTION

[0023] Floating solar trackers, such as those described herein, can be used on large bodies of water such as oceans, lakes, ponds, man-made reservoirs, and the like. Use of a mechanical support structure can help to position PV panels properly to maximize sunlight exposure. Such mechanical support structures can be affixed to a floating structure, such as a pontoon-like structure, to enable angular rotation of the PV panels appropriately while floating on top of a body of water.

[0024] FIG. 1 schematically illustrates a floating solar tracker 100. Floating solar tracker 100 can include solar panels 110, a mechanical support structure 120, and a floating structure 130. Solar panels 110 can be supported by mechanical support structure 120 that is secured to floating structure 130. Solar panels 110 can be arranged in a row, mounted on two purlins 121. The purlins 121 can be mounted on any suitable number of pivot arms (not shown). At the midpoint or approximately the midpoint of each pivot arm, a hole can be provided that forms a bearing having an axis of rotation aligned with the row of panels 110. Each of these bearings can be mounted on a respective axle (not shown), which can be at the top of legs 122 that act as a support structure. Such a bearing-axle assembly can allow the pivot arms, and therefore the solar panels 110 attached to purlins 121 which are attached to the pivot arms, to rotate about an axis aligned with the row of panels 110.

[0025] Floating structure 130 can be a pontoon-like structure that includes a pair of hollow cylinders 132. Hollow cylinders 132 can be cylinder structures, such as polyvinyl chloride (PVC) pipes, having a positive buoyancy to facilitate floating on a body of water. Hollow cylinders 132 can also be of a color to maximize light reflection, such as white. The ends of hollow cylinders 132 can be capped or sealed by sealing mechanism 136 so as to prevent hollow cylinders 132 from filling with water from the body of water in which the floating solar tracker 100 is deployed.

[0026] Mechanical support structure 120 can be secured to floating structure 130 via legs 122. Each leg 122 can include an anchor band 123. Anchor band 123 can have a diameter sufficient to fit around the perimeter of hollow cylinder 132 such that anchor band 123 tightly secures mechanical support structure 120 to hollow cylinders 132.

[0027] The rotation of the solar panels 110 can be powered by a motor, which is not specifically illustrated in FIG. 1. Illustratively, the motor can drive a drive shaft 124. A pinion gear 125 can transfer rotational power and torque from the drive shaft 124 to arc gears 126. The legs 122, pivot arms (not shown), and arc gear 126 together optionally provide an A-frame assembly. Although the non-limiting configuration illustrated in FIG. 1 includes two A-frame assemblies, it should be appreciated that there could be more than two A-frame assemblies per floating solar tracker 100. The arc gears 126 respectively can be connected to the pivot arms (not shown) and rotate the pivot arms about their respective axles (not shown). In this way, the solar panels 110 can be rotatably coupled to the drive shaft 124 (and thus the motor). Additional details on the rotation of solar panels 110 can be found in U.S. Patent Publication No.

2018/0091088 Al, entitled“Systems and Methods for Rotatably Mounting and Locking Solar Panels,” U.S. Patent Publication No. 2016/0365830 Al, entitled“Systems and Methods for Rotating Photovoltaic Modules,” and U.S. Patent Application No. 16/201,896, entitled“Systems and Methods for Improving Light Collection of Photovoltaic Panels,” the contents of each of which are incorporated herein by reference in their entirety.

[0028] For illustration purposes, there are six solar panels 110 shown in FIG. 1. It should be appreciated, however, that floating solar tracker 100 can include more or less solar panels 110. Similarly, mechanical support structure 120 can include more or fewer purlins 121. Floating structure 130 can include more than two hollow cylinders 132 or can include only one hollow cylinder. Hollow cylinders 132 need not be cylindrical in shape. The hollow cylinders 132 could be hollow, elongated rectangular or hexagonal extrusions or hollow elongated elements of any custom shape.

[0029] In cases of inclimate weather, such as high winds, rain, and/or high sea states, solar panels 110 of floating tracker 110 can be rotated and/or locked into a stow position, such as a horizontal position relative to the body of water or floating structure 130. For example, solar panels 110 of floating solar tracker 100 can be rotated and/or locked into place in accordance with the descriptions found in U.S. Patent Publication No. 2016/0365830 Al, entitled“Systems and Methods for Rotating Photovoltaic Modules,” U.S. Patent Publication No. 2018/0091088 Al, entitled“Systems and Methods for Rotatably Mounting and Locking Solar Panels,” and U.S. Patent Application No. 16/246,216, entitled“Mounting Systems for Solar Photovoltaic (PV) Power Plants,” the contents of which are incorporated herein by reference in their entirety.

[0030] In an effort to deter wildlife from resting on purlins 121 and/or drive shaft 124, a sharp or prickly wire (not shown in FIG. 1) can be strung above purlins 121 and/or drive shaft 124. [0031] FIG. 2 schematically illustrates the example floating solar tracker 200 anchored to a surface beneath a body of water. Anchoring of floating solar tracker 200 can minimize the distance in which floating solar tracker 200 can move within a particular body of water. Floating solar tracker 200 can be anchored, for example, to a stationary surface beneath a body of water, such as sand or a concrete block within the body of water using an anchor line 210. Anchor line 210 can be of sufficient length so as to maintain floatation of floating solar tracker 200 on the surface of a body of water.

[0032] FIG. 3 schematically illustrates an example floating solar tracker 300 having reflective plastic material 310 draped between the hollow cylinders 136. Albedo is the proportion of incident light or radiation reflected by a surface. The albedo of water is poor, which in turn will reduce the amount of light reflected off the water and captured by the solar panels 110. In some variations, such as the variation illustrated in FIG. 3, floating structure 130 can include a reflective plastic material 310 draped on top of hollow cylinders 132 and stretching between hollow cylinders 132. Reflective plastic material 310 can be polyvinylidene fluoride or polyvinylidene difluoride (PVDF). Reflective plastic material 310 can have a higher albedo than water, thus increasing the amount of light reflected back to solar panels 110.

[0033] Salt residue from bodies of salt water, such as the ocean, or other film deposits from rain, such as acid rain, can cause residue build up on solar panels 110. To facilitate cleaning of solar panels 110 or powering of the motor to drive movement of the solar panels 110 (as previously described in FIG. 1), another example floating solar tracker 400 illustrated in FIG. 4 can store liquid 436 within one or more of hollow cylinders 132. In some variations, liquid 436 can be water, such as desalinized water or fresh, filtered water used to clean solar panels 110.

For example, solar tracker 100 can include solar panels 110, mechanical support structure 120, and floating structure 130, such as those described in FIG. 1, along with all components described in FIG. 1. In addition to the components described in FIG. 1, mechanical support structure 120 can also include a central purlin 440. Central purlin 440 can include an integrated water pipe for washing off residue collected on solar panels 110. Central purlin 440 can receive water through piping (not shown) stretching from central purlin 440 to hollow cylinders 132. In this example, hollow cylinders 132 of floating structure 130 can be partially filled with water, such as desalinized water or fresh, filtered water. It is noted that filling of the hollow cylinders should be to a level so as to maintain floatation of floating solar tracker 400. [0034] FIG. 5 schematically illustrates a perspective view of an example floating solar tracker 500 with a sprinkler panel cleaning system. In variations such as where liquid 436 is water, such as desalinized water or fresh, filtered water, the water can be dispersed from central purlin 440 (not shown in FIG. 5) via one or more sprinklers 542.

[0035] FIG. 6 schematically illustrates an example system 600 of multiple floating solar trackers coupled together and arranged in rows. For example, FIG. 6 schematically illustrates a perspective view of an example tracking system 600 floating on a body of water 610. Body of water 610 can be any body of water suitable for floating solar trackers such as an ocean, lake, pond, man-made reservoir, and the like. Tracking system 600 can include a plurality of rows 620 of multiple floating solar trackers 630 (i.e., such as floating solar tracker 100, 200, 300, 400, 500) and slew drive motor 640 which can be coupled to any suitable number of rows 620, e.g., to each of rows 620, to only one of rows 620, or to more than one of rows 620, so as to rotate solar panels 110 of floating solar trackers 630 of that row. Slew drive motor 640 is described in detail in U.S. Patent Publication No. 2016/0365830 Al, entitled“Systems and Methods for Rotating Photovoltaic Modules,” the contents of which are incorporated herein by reference in its entirety. Optionally, tracking system 600 can further include one or more structural members 650 attaching together multiple rows 620. Multiple floating trackers 600 can be coupled together so as to form a larger tracking system 600. Each floating solar tracker 630 can be coupled to other solar trackers in the same row via a transverse member spanning the row 620 (not shown). Any suitable number of floating solar trackers 630 can be coupled to one another. Such coupling can occur for example, in some variations, via one end of hollow cylinder 132 (e.g., the end to be coupled to another hollow cylinder) can be threaded so as to connect to another hollow cylinder. Coupling together of multiple floating solar trackers can reduce effects of waves or water movement of the body of water on which the floating solar trackers are deployed. In order for slew drive motor 640 to drive the position of solar panels 110 of each floating solar tracker 630 in a row 620, each floating solar tracker 630 can also be coupled together via respective drive shafts 124. A description of this coupling and rotational driving can be found in U.S. Patent Publication No. 2016/0365830 Al, entitled“Systems and Methods for Rotating Photovoltaic Modules.”

[0036] In the descriptions above and in the claims, phrases such as“at least one of’ or“one or more of’ may occur followed by a conjunctive list of elements or features. The term“and/or” may also occur in a list of two or more elements or features. Unless otherwise implicitly or explicitly contradicted by the context in which it is used, such a phrase is intended to mean any of the listed elements or features individually or any of the recited elements or features in combination with any of the other recited elements or features. For example, the phrases“at least one of A and B;”“one or more of A and B;” and“A and/or B” are each intended to mean “A alone, B alone, or A and B together.” A similar interpretation is also intended for lists including three or more items. For example, the phrases“at least one of A, B, and C;”“one or more of A, B, and C;” and“A, B, and/or C” are each intended to mean“A alone, B alone, C alone, A and B together, A and C together, B and C together, or A and B and C together.” In addition, use of the term“based on,” above and in the claims is intended to mean,“based at least in part on,” such that an un-recited feature or element is also permissible.

[0037] The subject matter described herein can be embodied in systems, apparatus, methods, and/or articles depending on the desired configuration. The implementations set forth in the foregoing description do not represent all implementations consistent with the subject matter described herein. Instead, they are merely some examples consistent with aspects related to the described subject matter. Although a few variations have been described in detail above, other modifications or additions are possible. In particular, further features and/or variations can be provided in addition to those set forth herein. For example, the implementations described above can be directed to various combinations and sub-combinations of the disclosed features and/or combinations and sub-combinations of several further features disclosed above. In addition, the logic flows depicted in the accompanying FIGS and/or described herein do not necessarily require the particular order shown, or sequential order, to achieve desirable results. Other implementations may be within the scope of the following claim.