BR112014032277B1 - WATERLESS SOLAR PANEL CLEANING SYSTEM FOR CLEANING SOLAR PANELS - Google Patents

Abstract

waterless solar panel cleaning system for cleaning solar panels from a plurality of solar arrays. system and method for cleaning solar arrays from solar panels. each solar row has an upper edge raised from ground level more than a lower edge to provide a slope of the solar row. a cleaning assembly operates to clean a surface of the solar panels. a support frame supports the cleaning assembly and allows the cleaning assembly to move (1) up and down in the solar row width direction and (2) in the solar row length direction. operation and movement of the cleaning assembly is controlled in order to clean a surface of the solar panels during downward movement of the cleaning assembly. the cleaning assembly is preferably not operative during its vertical upward movement. during downward movement, the cleaning assembly removes dirt, debris and dust from the surface of the solar panels and generates an airflow to blow away dirt, debris and dust. the system additionally includes a guide system to move the cleaning assembly to align with successive rows of solar panel.

Description

CROSS REFERENCE TO RELATED ORDERS

[0001] This patent application claims priority to US Patent Application Serial Number 13/917,285 filed June 13, 2013, which claims prior priority of US Application Serial No. 13/751,903, filed on January 28, 2013, which claims priority of US Serial Number Provisional Patent Application 61/663,827 filed June 25, 2012 and 61/725,280 filed November 12, 2012 and also claims priority of Application Provisional Patent Serial Number US 61/819,107 filed May 3, 2013. The entire contents of all preceding applications are incorporated by reference into this document.

FUNDAMENTALS OF THE INVENTION

[0002] Changing global climate challenges and energy security demands have made the development of renewable energy alternatives vital for the future of humanity. The use of direct radiation from the sun on solar panels can potentially produce more than enough energy to satisfy the entire planet's energy needs. As the price of solar power decreases and that of conventional fuels grows, the solar business has entered a new era of worldwide growth.

[0003] In order to bring technologies to exploit solar energy a step closer to oil parity, efficiency rates of solar systems must improve.

[0004] Solar panel surfaces are typically made of high quality glass and the efficiency of the renewable energy they generate depends, among other things, on the cleanliness of the glass surfaces. Due to dust and other dirt and/or debris on the surfaces of solar panels, energy losses in some cases can reach more than forty percent (40%).

[0005] As most solar parks or other installations and concentrations of solar panels are located in desert areas, where solar radiation is intense and exposure to dusty conditions is high, cleaning the solar panels becomes essential.

[0006] Currently, existing solar panel cleaning processes are expensive, labor intensive and consume large volumes of water. Due to water scarcity in desert areas, solar panel cleaning using water or wet cleaning is a major obstacle for the solar industry.

OBJECTS AND SUMMARY OF THE INVENTION

[0007] An object of the present invention (hereinafter referred to as "the invention") is to provide a system and method that will make solar panel cleaning simple, efficient, and which could be water-free.

[0008] Another object of the invention is to provide a system and a method that will make the solar panel cleaning process automatic and economical.

[0009] Yet another object of the invention is to provide such a system for the cleaning process that will require minimal maintenance and supervision with low-cost construction.

[0010] Yet another object of the invention is to provide such a system and a method that will achieve high quality cleaning along with a high level of reliability in all climates and topographical conditions. The system and method must be adaptable to existing ones as well as to newly built solar parks.

[0011] Another object is to provide a system for cleaning a plurality of rows of solar panels.

[0012] According to the present invention, a solar panel cleaning system and method is provided for cleaning solar panels from a plurality of solar arrays. The solar rows each have a length and width, and the solar rows are slanted and have an upper end and a lower end in the width direction of the solar row, the upper end being raised to a higher position than the lower end. The cleaning system comprises a cleaning apparatus that is selectively operative to clean a solar panel surface of a solar array; a support frame supporting said cleaning apparatus, said support frame being configured to selectively move said cleaning apparatus in both said width direction and said length direction over a surface of the solar array; and a controller coupled to said cleaning apparatus and support frame to selectively move said cleaning apparatus in said solar row length direction and to selectively move said cleaning apparatus up and down in said solar row width direction. between said upper and lower ends, and causing said cleaning apparatus to clean a solar panel surface of the solar array during a downward movement of said cleaning apparatus in said solar array width direction. The system additionally includes a guide system to move the cleaning assembly to align successive rows of solar panel.

[0013] In a specific embodiment, the cleaning apparatus is caused to clean the solar surface during a downward movement of the cleaning apparatus in the width direction of the solar row.

[0014] More specifically, a control system controls the operation of the cleaning assembly and movement of the cleaning assembly to effect a cleaning cycle during the downward movement of the cleaning assembly. The control system then causes the cleaning assembly to move along the solar row to a new position where the control system performs a new cleaning cycle. The process continues along the length of the solar array. Thereafter, the cleaning assembly can be brought into a storage or resting position.

[0015] A combined movement along both the width and length directions of the solar array can be implemented, especially in the last stage of downward movement of the cleaning assembly. This creates a diagonal downward path of the cleaning assembly.

[0016] A guide system extending substantially perpendicular to the solar arrays is provided to move the cleaning assembly to successive solar arrays to clean the plurality of successive solar arrays.

BRIEF DESCRIPTION OF THE FIGURES

[0017] The invention, together with additional objects and advantages thereof, can be better understood by referring to the following description, taken in conjunction with the accompanying figures, in which similar reference numerals identify similar elements and in which:

[0018] FIG. 1 is a top view of a first embodiment of a solar panel cleaning system in accordance with the invention;

[0019] FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, showing the solar panel cleaning system in a downward movement cleaning the solar panel;

[0020] FIG. 3 is a sectional view taken along line 3-3 in FIG. 1;

[0021] FIG. 4 is a detailed cross-sectional view of the rotary cleaning assembly;

[0022] FIG. 5 is a sectional view taken along line 5-5 in FIG. 1;

[0023] FIG. 6 is a cross-sectional view of a second embodiment of a solar panel cleaning system in accordance with the invention; and

[0024] FIG. 7 is a side view of an embodiment of the invention for cleaning multiple rows of solar panel.

DETAILED DESCRIPTION

[0025] Referring to the accompanying figures in which the same reference characters refer to identical or similar elements, FIG. 1 is a top view of an exemplary embodiment of a solar panel cleaning system in accordance with the invention, some details of which are omitted for reasons of simplicity and clarity.

[0026] The solar panel cleaning system is shown in combination with a row of solar panel assemblies 111 (hereinafter referred to as "the solar row"). Solar array 111 comprises a plurality of solar panels of most of any type and constructions known to those skilled in the art. For example, a single solar panel typically has a face area of less than about one square meter. A length of solar array 111 can vary from about a few meters to a few kilometers. A width of solar array 111 ranges from about one meter to about several meters.

[0027] The surface of each solar panel in solar array 111 is preferably made of transparent material such as glass. The solar panel surface can be coated with a repellent coating that facilitates the surface cleaning process.

[0028] As shown in FIG. 2, the solar row 111 is constructed in an angular or slanted position towards the sun, which creates a lower edge (the right edge) and a higher edge (the left edge) of the solar row 111.

[0029] A pair of parallel rails 112, 113 are connected to the upper edge and the lower edge of the solar array 111, respectively. Rails 112 and 113 can be made of steel, fiberglass, or other metallic or non-metallic materials. In some embodiments of the invention, rails 112 and 113 can be used as electrical conductors, i.e., electrical cables can be disposed on an interior of rails 112, 113 or along an outer surface of rails 112, 113, or the rails. 112, 113 can be made of electrically conductive material and can be used as electrical conductors for the system.

[0030] The cleaning system includes a support frame that allows bidirectional movement of a cleaning assembly, described below. This bidirectional movement allows the cleaning assembly to move along the solar array in two directions — along the length of solar array 111 (left-right in FIG. 1) and in the direction of the width of solar array 111. The frame The support frame includes a main frame 114 which is configured to be movable along the length of the solar array 111. Main frame 114 is preferably made of aluminum building profiles, but other materials such as steel or fiberglass may be used. Support elements 115 are connected to main frame 114 for support, four of which are shown in FIG. 1

[0031] Several wheels having different functions are connected to the main frame 114, there being a total of six of these wheels in the illustrated mode, although the number, function and position of the wheels may vary. These wheels allow the main frame 114 to move along the solar row 111 in the solar row length direction. Of these wheels, three wheels 126 support the main frame 114 in a direction perpendicular to the surface of the solar panels of the solar array 111 (See FIG. 1). The other two wheels 133 support the main frame 114 in a direction parallel to the surface of the solar panels of the solar array 111. Instead of two wheels, 133, other numbers of wheels can be used, such as four.

[0032] A drive wheel 132 is arranged in the same orientation as wheels 126, that is, in a perpendicular direction to the surface of the solar panels of the solar row 111 and is driven by a drive system 117, such as a motor, in the forward and reverse directions. Drive wheel 132 functions to drive main frame 114 along the solar row in the solar row length direction. The motor in drive system 117 can be any type of motor or other system capable of generating a motive force, such as a DC motor. When a motor is present in drive system 117, an encoder is connected to the motor and reads the angular position of the motor. The angular position is converted by a processor into a determination of the location of the cleaning system along the solar row 111. Drive wheel 132 can drive frame 114 along the solar row in two directions.

[0033] A motion limitation sensing device 116, e.g. a limit switch or a sensor, is located on the upper edge of the main frame 114 (See FIG. 1).

[0034] A subframe 136 is configured to be movable along the mainframe 114. When the mainframe has a longitudinal axis as shown, the subframe 136 can be considered to move in the longitudinal or longitudinal direction or length along the frame main 114. Subframe 136 is preferably made from aluminum profiles, although other materials may be used.

[0035] Subframe 136 supports at least one and preferably a plurality of cleaning apparatus, such as rotational cleaning units or rotational cleaning apparatus 124 (hereinafter referred to as an "RCA"). As shown in FIGS. 1 and 2, subframe 136 supports two RCAs 124. Each RCA 124 is connected to subframe 136 through a respective center shaft 324 and bearings (not shown) to enable the 124 RCAs to rotate in subframe 136. each RCA is shown in broken lines 325 in FIG. 1.

[0036] A drive system 125 is provided for driving RCAs 124. Drive system 125 may comprise a DC motor, or another type of motor or source of motive power may be used. A power transfer system is provided to transmit the driving force from the drive system 125 to the 124 RCAs and convert the driving force into rotational force to rotate the RCAs 124. For example, a pulley 128 can be connected to the drive system 125 and belts 127 wrapped around the pulley 128 and the RCAs 124. There may be a belt 127 wrapped around each RCA 124 and the pulley 128. The drive system 125 causes the pulley 128 to rotate and the pulley 128 to rotate. cause the belts 127 to move, which in turn causes one axis of each RCA 124 to rotate. Belts 127 can be made of polyurethane and be round, but other types of belt shapes, such as V-belts or timing belts, and other materials can be used.

[0037] In a preferred embodiment of the invention there are two RCAs 124, but the cleaning system in accordance with the invention is equally usable with only a single RCA 124 or with three or more RCAs 124.

[0038] Also, a preferred embodiment of the invention, the RCAs 124 have approximately octagonal shapes as indicated in FIG. 4, but other shapes such as cylindrical, square, hexagonal and any other flat or polygonal shapes can be used without departing from the scope and spirit of the invention.

[0039] Referring further to FIG. 4, on the outer surface of each RCA 124, one or more flexible fins 140 are connected via a connection technique to a retaining member of the RCA 124. For example, the fins 140 can be structured to provide a quick connector between the fins 140. and the recesses of the outer surface of the RCA retaining member 124. Using a quick connector, several types of which are known to those skilled in the art, periodic cleaning of the fins 140 can be easily implemented by removing them from engagement with the RCA 124 , cleaning them and then reconnecting them to the RCA 124. Additional details about the fins 140 and their connection to the RCA 124 are defined below.

[0040] Referring back to FIG. 1, a winch cylinder 130 has one or more ropes or ropes (hereinafter referred to as ropes for ease of description) 131 attached and partially wound thereon. Rotation of winch cylinder 130 controls winding or unwinding of cables 131. This controlled winding and unwinding drives subframe 136 upward along the angled slope of mainframe 114, ie, longitudinally along mainframe 114. As illustrated, winding the cables 131 by the winch cylinder 130 causes upward movement of the subframe 136 along the solar arrays of the solar array 111, while the unwinding of the cables 131 by the winch cylinder 130 causes the downward movement of the subframe 136 along the solar panels in solar row 111 (which is aided by the gravitational pull of secondary frame 136 downward). Winch cylinder 130 is driven by a drive system 118, which may include a DC motor.

[0041] Cables 131 are preferably made of a composite material such as KEVLAR® as an outer sleeve and flexible insulated conductor wire as the inner core within the sleeve. An outer diameter of each cable 131, i.e. the outer diameter of the outer sleeve, can be about 7 mm and the diameter of the inner core can be about 4 mm. Other materials, constructions and diameters can be used for cables 131. Additional details regarding the drive system 118 and the connection of cables 131 are described below.

[0042] A power source 191 is provided to give power to the cleaning system, for example, one or more batteries that may be rechargeable, replaceable, etc. For example, the power source 191 may provide power to a programmable control unit 120 that controls the operation of the cleaning system, including the operation and movement of the cleaning assembly through various motors. Power source 119 may itself include an array of solar panels 171 attached to main frame 114. Solar panels 171 are designed to charge any batteries of power source 119 during daylight hours and when sunlight is received by the solar panels 171. The power supply 119 and solar panels 171 are connected to the main frame 114 to be mobile therewith and thus allow the cleaning system to operate independently without connection to any other source of electricity (other than that provided in the panels solar 171 and onboard power supply 119).

[0043] Various sensing devices or sensors are provided in the cleaning system. For example, sensor 129 is positioned on rail 112 (near the left edge in the construction shown in FIG. 1) to detect maximum leftward movement of main frame 114 on rails 112, 113. Likewise, sensor 135 is positioned over track 112 (near the right edge in the construction shown in FIG. 1) to detect a maximum rightward movement of main frame 114 on tracks 112, 113. Sensor 129 and/or sensor 135 can alternatively be placed on track 113. Sensor 116 is positioned on main frame 114 (near a top edge in the construction shown in FIG. 1) to detect maximum upward movement of secondary frame 136 on main frame 114. Likewise, sensor 134 is positioned on main frame 114 (near a lower edge in the construction shown in FIG. 1) to detect a maximum downward movement of subframe 136 to mainframe 114.

[0044] A drive system motor encoder 117, when present, transmits limits and positions signals to the programmable control unit 120 which allows for effective operation of the system. In some cases, an encoder can replace sensors 129 and 135 by feeding a cleaning assembly position corresponding to the positions of sensors 129 and 135. Programmable control units 120 are very well known in the industry and will not be described in detail in this document.

[0045] FIG. 2 shows details of the secondary frame 136 which is movable down and up along the main frame 114, in the width direction of the solar row 111. To provide the solar row 111 with its angularity with respect to ground level 150, an angular construction 139 supports the solar row and has a greater vertical degree foot construction closer to the upper edge of solar row 111 and a lesser vertical degree foot construction nearer to the lower edge of solar row 111.

[0046] The secondary frame 136 mounted on a plurality of wheels 137, for example, four wheels, which rotate perpendicularly to the surface of the solar panel, that is, its axis of rotation is perpendicular to the normal of the surface of the solar panels of the solar row 111. One or more additional wheels 138, e.g. four wheels, are mounted on subframe 136 to rotate parallel to the surface of the solar panel, i.e. its axis of rotation is parallel to the normal of the surface of the solar panels of the solar array 111.

[0047] Wheels 137, 138 are connected via bearings (not shown) to subframe 136 and the roller against the surface of the profiles making up mainframe 114. Wheels 137 and 138 therefore enable subframe 136 to move to up and down along main frame 114. This movement of secondary frame 136 relative to main frame 114 and solar row 111 is independent of the movement of main frame 114 along the length of solar row 111.

[0048] In the situation shown in FIG. 2, the RCAs 124 rotate in the same direction, counterclockwise, as indicated by arrow 141. This direction of rotation preferably occurs as the secondary frame 136 moves down along the main frame 114. The RCAs 124 are driven by the system drive 125 through pulley 128 and belts 127. Belts 127 drive the two RCAs 124 through the two additional pulleys (not shown) that are attached to each RCA 124.

[0049] Each RCA 124 in FIG. 2 includes four blades 140 which, through a control frame originating from the 125 drive system, rotate at approximately 170 rpm, although other rotation speeds are feasible. As fins 140 rotate and secondary frame 136 moves downward, an outer portion of fins 140 touches, sweeps and cleans the surface of solar array solar arrays 111. Rotation of fins 140 creates a blowing effect which helps to push the dirt, debris and dust on the surface of the solar panels downward as a result of the tilt of the solar row 111.

[0050] FIG. 2 also shows a connection between the cable 131 that winds and unwinds about the axle coupled to the winch 130 (See FIG. 1) and an upper edge of the secondary frame 136, near a central region of an upper profile that forms part of the secondary frame 136 Each cable 131 can be connected in the same way for the axle and subframe 136. When the winch cylinder 130 rotates in one direction, the length of the cables 131 between the axle of the winch cylinder 130 and the subframe 136 becomes becomes shorter and subframe 136 is moved up. When the winch cylinder 130 rotates in the opposite direction, the length of the cables 131 between the axle of the winch cylinder 130 and the subframe 136 becomes longer and the frame 136 moves downward. An angular condition must be defined between a long axis of the winch cylinder 130 and the ropes 131, the angle of which will ensure an orderly winding arrangement of the ropes 131 on the winch cylinder 130.

[0051] Alternatively, the cables 131 can be connected to the center of the winch cylinder 130 and to two opposite sides of the upper profile of the secondary structure.

[0052] Preferably, the cables 131 in this configuration would also create an angle between them that allows for orderly rolling of the cables 131 in and out of the winch cylinder 130.

[0053] In lieu of the foregoing structure that gives motion to subframe 136 relative to mainframe 114, other motion systems that allow subframe 136 to move along mainframe 114 are contemplated to be within the scope of the invention. For example, such an alternative includes a system with a timing belt path and a timing pulley that is driven by a gear motor.

[0054] FIG. 3 shows the top rail 112 and support member 115 each having a substantially square cross-section, although other shapes are possible. Wheel 126 is mounted on support element 115 to rotate against an upper surface of track 112. Wheel 126 axis of rotation is perpendicular to the normal to the surface of the solar arrays of solar array 111. Wheel 133 is also mounted on the wheel element. bracket 115 for pivoting against a side surface of rail 112. The axis of rotation of wheel 126 is parallel to normal to the surface of the solar arrays of solar array 111. An assembly is formed by support element 115, wheels 126 mounted thereto, and wheel 133 mounted to them. There are three such assemblies, as shown in FIG. 1.

[0055] Another assembly includes one of the support elements 115, between the wheels 132 and the drive system 117. These four assemblies allow mobility of the cleaning assembly along the solar row 111 in two directions.

[0056] FIG. 4 shows the RCA 124 and fins 140 connected to them. As shown in FIG. 4, the RCA 124 preferably has an octagonal shape with eight cavities 143, although, as mentioned above, other polygonal shapes, flat and cylindrical shapes may be provided for the RCA 124.

[0057] In a preferred embodiment of the invention, the fins 140 bend around solid core elements 142. The core elements 142 can also be connected to the fins 140 or as separate elements. Each fin 140, after being folded around a respective one of the central elements 142, slides into a respective cavity 143 in the RCA 124 and is locked in the cavities 143 by an appropriate locking mechanism. For example, the locking mechanism may include at least one o-ring flexible side (not shown).

[0058] When the RCA 124 rotates, the fins 140, with their locking elements 142 are pushed towards the projections of the cavities 143 by centrifugal force and are locked and rotated together with the RCA 124. Although FIG. 4 shows four fins for the RCA 124, any other number of fins can be used, from one to eight when the octagonally shaped RCA 124 has eight cavities 143.

[0059] In a preferred dry cleaning system and method, the fins 140 can be made of fabric. A preferred fabric is microfiber fabric, which is known to professionals for its cleanliness and durability qualities. Microfiber fabrics are also very soft and they will not harm the surface of the solar panels. Other fabrics and/or materials are also viable. For a wet cleaning method and system, fins 140 should be made from different materials and/or fabrics.

[0060] Regardless of the type of cleaning system, fabrics can be coated with silicone, neoprene or other rubber-like materials. Under some conditions, combinations of different types of fins can be used. The quick-connect capability between fins 140 and RCA 124, described above, facilitates quick and easy replacement of fins 140 so that they can be periodically washed. The preferred quick connection described above is just one way to connect the fins 140 to the RCA 124 and other types of quick connection between the fins 140 and the RCA 124 are also considered part of the invention, such as Velcro strips, zippers and the like.

[0061] A length of the RCA 124 and the length of the fins 140 may vary. Preferred sizes of fins 140 are between about 400 mm and a preferred length of RCA 124 is about 1400 mm

[0062] FIG. 5 shows a winch assembly 80 that includes the winch cylinder 130 and the ropes or cables 131 that wind over the winch cylinder 130 and connect the winch cylinder 130 to the subframe 136. As explained above, each cable 131 has an inner conductor core. and KEVLAR ® as an outer sleeve, with other constructions and materials for cables 131 being contemplated by the inventors.

[0063] Drive system 118 drives and rotates the winch cylinder 130 through a pulley 160 that receives the driving output of the drive system 118, a belt 161 that goes around the pulley 160 and another pulley 162 that is connected to the winch 130. Drive system 118 can include a DC motor that can rotate in two directions, ie cause clockwise and counterclockwise rotation of pulley 160. Rotational force thus can be transferred from drive system 118 on the winch cylinder 130 via a belt or reduction gear. The rotation speed of the winch assembly 80 can be about 100 rpm, although other rotation speeds can be used.

[0064] The winch assembly 80 also includes two driveshafts 163 mounted on respective bearings 164, which in turn are housed in part and supported by the two respective bearing housings 165. Bearing housings 165 are connected to main frame 114 and more specifically to a top profile whose main frame 114 is formed (See FIG. 1). A drive shaft 163 at one end of the winch cylinder 130 passes through the pulley 162 and another drive shaft at the opposite end of the winch cylinder 130 passes through an end disc 168.

[0065] Electrically conductive brushes 166 are located in each of the bearing housings 165 and transmit electricity to the two cables 131 through connectors 167 while the winch cylinder 130 is rotating. Two electrical wires 169 connect the electrically conductive brushes 166 to an electrical power supply through the control unit 120 (See FIG. 1).

[0066] In one modality, two drive systems 118 are provided. In this case, end disc 168 is replaced by another pulley, pulley similar to 162.

[0067] A locking mechanism 170 is optionally provided to lock the secondary frame in position. Locking mechanism 170 uses a solenoid which, when energized, locks the subframe 136 in, for example, the upper position, while the cleaning system is in sleep mode.

[0068] When the drive unit 120 gives a command that connects the drive system 118 of the winch assembly 80 to the electrical power supply at a certain polarity, the winch cylinder 130 rotates in a predetermined direction, the cables 131 become if shorter and the subframe 136 moves up in the solar row width direction. Once secondary frame 136 reaches the upper end of main frame 114, sensor 116 provides a signal to control unit 120. At this stage, control unit 120 provides drive system 118 with signals or electrical conditions that cause that the secondary frame 136 moves downward, preferably at a predetermined speed, in the direction of the width of the solar array. These electrical conditions depend, for example, on one or more of the following: an angular position of the solar panel row 111, secondary frame weight 136 and the specifications of the RCA 124. The electrical conditions can be one or more of the following: the voltage and the power polarity for the drive system 118, the operation of a motor of the drive system 118 as a braking generator under short circuit condition, and the operation of the motor of the drive system 118 as a braking generator on loads. such as power resistor or diodes in any possible configuration. While other arrangements are possible, two possible configurations include Zener-type diodes or diodes in serial connection.

[0069] Another important load arrangement that can control the descending speed of the secondary frame 136 is the connection of the drive system 118, while it operates as a generator for a special electronic circuit that converts the generating power of the drive system 118 into a voltage high enough that it can charge the batteries in power source 119, to which it is connected in an electrical circuit. This arrangement can reduce the energy required to operate the cleaning system. All of these electrical conditions are designed to control the descending rate of subframe 136 and form part of the present invention.

[0070] When the secondary frame 136 begins its downward movement, the control unit 120 connects the cables 131 to the power supply in a certain polarity that causes the RCAs 124 to rotate at a predetermined speed and in a desired direction and from this In this way, clean the surface of the solar panels of solar array 111.

[0071] With regard to more specific details about an exemplary operation and control of the cleaning system, in any of the modalities described above, during the vast majority of times, the system remains in the stationary position with power source 191 connected to and loaded by solar panels 171 (this location is referred to as "the home station"). The control unit 120 can trigger a command that will start the system cleaning process. This command can come from a pre-programmed schedule or a command initiated by a control center of the solar panel installation. The solar panel installation can include several solar rows and therefore a cleaning system for each solar row. The solar installation will therefore have several cleaning systems. Optionally, each cleaning system has its own address and location code.

[0072] The trigger command is independent of the system and each system can be autonomous. The solar panel installation control center can optionally continuously monitor the output power of the solar array(s) 111 at installation, the location of each cleaning system and optionally can detect technical problems of any system.

[0073] Optionally, the cleaning process can be controlled by a control unit that receives and factors in dynamic information, such as local weather conditions (present and forecast), sandstorms and other factors that negatively impact the output strength of the panels solar arrays in the solar row 111. These factors can be taken into account in order to trigger the cleaning process, or a schedule for cleaning the solar panels. Usually, this information is provided by adequate provision of several servers connected to the control unit, which are omitted from the description for the sake of simplicity. A person skilled in the art would readily understand from the disclosure in this document how the control unit would receive and process information of value in determining a cleaning regime for the solar panels in the solar installation and how to implement this regime using the cleaning system described in this document .

[0074] Since the monitoring process can calculate the output force for any given solar array 111, the control unit can be configured through suitable analysis techniques to detect any broken or stolen solar panel.

[0075] When the cleaning system is in its domestic station, the secondary frame 136 is preferably at the upper end of the main frame 114, the main frame 141 in the rightmost position relative to the solar row 111, and the locking mechanism 170 is in a locked position which does not require force. None of the 117, 118, 125, drive systems or motors operate.

[0076] Once the cleaning system receives a start or start command, the drive system 118 activates the winch cylinder 130, the locking mechanism 170 releases the drive system 118 and secondary frame 136 begins to move to short. The descending rate of subframe 136 is controlled as explained above. The drive system 125 also begins to rotate and causes rotation of any RCAs 124 coupled thereto, for example two in the illustrated embodiment. Rotation of the RCAs 124 causes the fins 140 to rotate to clean the surface of the solar panels in solar row 111, pushing dust, debris and dirt down. Rotating the fins 140 also creates a blowing effect which helps to push and clean dirt, debris and dust down along the slope of the solar panels.

[0077] When the secondary frame 136 reaches the lower edge of the main frame 114, the sensor 134 transmits a signal to the control unit 120 which is configured to direct, in response to the signal from the sensor 134, the drive system 117 starts to rotate the initial movement of the main frame 114 along the length of the solar array in a leftward direction (in the embodiment of FIG. 6). The encoder of a motor in drive system 171 generates pulses during motor operation. After a predefined number of pulses, the motor stops by the command from the control unit 120. The number of encoder pulses can be correlated with a predefined distance along the length of the solar array 111. This predefined distance can be equal to the width of RCAs 124 minus a few centimeters to ensure minimal overlap between cleaning cycles.

[0078] During the operation of the drive system 117 and the movement of the main frame 114 along the solar row 111, the drive system preferably continues its operation and RCAs 124 with the fins 140 rotate and perform automatic cleaning. When main frame 114 reaches the preset travel distance, drive systems 117 and 125 stop, and drive system 118 starts rotating winch cylinder 130 in an upstroke mode and the system starts a new cleaning cycle.

[0079] Once the system reaches the end of the solar array length, sensor 129 provides a signal and drive systems 117 and 125 stop and the last cycle in this direction begins. Once the last cycle is complete, the system optionally starts a repeat cleaning process in the opposite direction until the system reaches its home station. This repeat cleaning process is optional.

[0080] Control unit 120 can be configured to provide any number of different cleaning cycles, with different movement directions of secondary frame 136 and main frame 114. It is possible to implement a control scheme in control unit 120 where there is only one unidirectional cleaning process such that at the end of this process, the system will continuously travel to the domestic station. Another control scheme is that the cleaning cycle will repeat more than once.

[0081] In some cases, the control unit 120 can cause a downward movement of the subframe 136 during movement of the main frame 114 along the length direction of the solar array, thus creating a diagonal cleaning path for the RCAs 124 which are mounted on subframe 136. This diagonal movement is especially advantageous in the last stage of downward movement of subframe 136 during a cleaning process.

[0082] There are also cleaning operations where the end of the cleaning process is started by the accumulated distances from the domestic station and not by the sensor 129. Another possible cleaning operation is to have two cleaning systems at each end of the solar row 111 and one sensor in a middle region of solar row 111. Each cleaning system can clean part of solar row 111 and therefore reduce the cleaning duration of a solar row 111 (in the middle).

[0083] Control of the system by the control unit 120, the sensors and the encoder are very well known to professionals in the electronics industry and therefore their description is omitted for reasons of simplicity.

[0084] FIG. 6 is a transverse, partial side view of another hand of a cleaning system in accordance with the invention. In this embodiment, the subframe 136 described above is not present and instead, the cleaning system includes a conveyor belt 224 that has a plurality of fins 240 on its outer surface. Conveyor belt 224 is installed along main frame 141 and driven by a motorized drive cylinder 228 arranged in a loop of conveyor belt 224 and in a lower section of main frame 114.

[0085] A tension cylinder 230 is also disposed in the conveyor belt loop 224 and in an upper section of the main frame 114. Tension cylinder 230 provides the necessary tension for the conveyor belt 224 to allow its movement. Conveyor belt 224 is driven so that its top part moves up over the solar panel row 111 in the width direction of the solar row without touching the surface of the solar panels of solar row 111, while the lower section of the conveyor belt 224 moves down over the solar panel row 111 and the fins 240 along this lower section touch, sweep, scrub and clean the surface of the solar panel on the solar row 111.

[0086] Support cylinders 229 arranged in a loop of conveyor belt 224 to support the movement of conveyor belt 224 and the upper section of conveyor belt 22, that is, prevent the upper section from contacting the lower section and negatively affect operation of the fins 240 along the bottom section.

[0087] The width of the conveyor belt 224 and the length of its fins 240 may vary. A preferred length of each fin 240 is about 400 mm. A preferred width of the conveyor belt is about 1200 mm. The fabric and/or material of the fins 240 is/are identical to those of the fins 140 described above. Fins 240 are preferably connected to conveyor belt 224 in a quick release connection, similar to that used above to connect fins 140 to RCAs 124.

[0088] Operation of the cleaning system in accordance with this embodiment is similar to that described with reference to the embodiment shown in FIGS. 1 - 5. So, for the vast majority of the time, the cleaning system is at your home station. When a start command is triggered, drive cylinder 228 is rotated and in turn starts causing conveyor belt 224 to move. Fins 240 on the lower section of conveyor belt 224 touch, sweep, scrub and clean the surface of solar arrays of solar row 111. After a preset travel distance of conveyor belt 224, whose preset travel distance 224 can be determined by data From an encoder attached to drive cylinder 228, drive cylinder 228 stops rotating and main frame 114 travels along the length of the solar array for a predefined distance. Then a new cleaning cycle begins. In all other respects, operation and control of this embodiment of the system is substantially identical to the description provided above with respect to the embodiment illustrated in FIGS. 1 - 5.

[0089] Regarding the power supply for any of the modes of the cleaning system described above, the system includes at least one rechargeable battery, preferably a sealed lead type battery, although other types of batteries can be used. Regardless of which battery is used, the battery provides the necessary power supply for system drive systems 117, 181, 125, respective motors and control unit 120 and electronics.

[0090] During the day while the system is in a stationary position, the battery can be recharged by solar panels 171. These panels 171 can be located at various locations throughout the system and can be washed through the cleaning system itself, ie , RCAs 124 or manually. It is essential to emphasize that there are other ways to provide the cleaning system with the necessary power supply. For example, the battery can be charged from an external source such as an existing power grid or the output of the solar farm or solar installation in which the cleaning system is used.

[0091] Electricity can also be powered without the battery. In such a modality, electricity can be transferred to the cleaning system through conductive rails and movable connectors similar to those used in the rail (train) industry. All such power supply arrangements form part of the invention.

[0092] Fig. 7 is a side view of an embodiment of the present invention for cleaning several rows of solar panel in a given Solar Park and two partial side views of solar row A and solar row B of the solar Park. Solar rows A and B are each substantially the same as or similar to solar row 111 of Fig. 1. Each solar row includes rails 112, 113 (referred to as rails or profiles 112a and 112b in Fig. 7). Only rail or profile 112a and 112b are shown in Fig. 7. Rails or profiles 113a and 113b, corresponding to rail 113 in Fig. 1, are not shown in Fig. 7. Fig. 7 illustrates in detail an apparatus for cleaning several rows of solar panel, combined with elements that have already been described with reference to Figs. 1 - 6. Therefore, not all elements of the basic system of Figs. 1 - 6 will be described or mentioned.

[0093] The main frame 311 of the system of Fig. 7 is mounted on four wheels 312 (various numbers of wheels may be used) which roll on two rails 313 (only one rail is shown in Fig. 7) that are directed perpendicular to the solar rows of the solar park. Two rails 313 is the preferred number of rails, but any number of rails can be used, or other types of paths such as concrete paths or the like can be used. Main frame 311 carries a cleaning apparatus as described in Figs. 1 - 6. A drive mechanism 320 drives main frame 311 in two directions along rails 313. Support frames 314, 315 are mounted on main frame 311 and an electric piston 316 is connected to support frames 314 and 315. Changing the position (ie extension) of piston 316 will change the height of shaft point 322. Piston 316 can be a hydraulic piston or a cable winch. The top frame 318 is connected via a shaft 322 to the support frames 314 and 315. The pivot point 322 allows the top frame 318 to change its angle relative to the main frame 311. Another electric piston 317 changes the frame's angular position 318 higher than the main frame 311. Piston 317 can be a hydraulic piston or a cable winch. 2112 and 2113 are two profiles that can be aligned with profiles 112 and 113 of the solar arrays, respectively.

[0094] A control unit 319 controls the position of the system in three dimensions with respect to solar arrays A and B. Input data to control unit 319 can be provided by sensors and encoders that are well known in the industry and are not described here. An electrical power supply such as batteries or an external electrical power supply is not described here. 111a, 112a and 111b, 112b are profiles or tracks of the solar rows A and B, respectively, of the solar park and correspond respectively to tracks 112, 113 of Fig. 1.

[0095] In the initial position, the cleaning system of the present invention is parked on the profiles 2112 and 2113 of the system of Fig. 7. The profiles 2112 and 2113 are in line with the profiles 112a and 113a (i.e., rails 112, 113 of Fig. 1) of solar array A. Upon receiving an initial cleaning command, the cleaning system moves from profiles 2112 and 2113 towards profiles 112a and 113a, respectively, to envelop profiles (rails) 112a and 113a (tracks 112 and 113), and starts the cleaning cycle of solar array A. This cleaning cycle has been described with reference to Figs. 1 - 6. Once the cleaning cycle is completed, the system of Figs 1-6 moves back from profiles 112a and 113a towards profiles 2112 and 2113 of the system of Fig. 7 until all of the cleaning apparatus is parked back on profiles 2112 and 2113.

[0096] At this stage, the control unit 319 provides a command for the drive mechanism 320 and the system of Fig. 7 moves on the rails 313 from solar row A towards solar row B. Fig. 7 comes close to solar array B, the sensors and encoders from the system of Fig. 7 transfer to the control unit 319 precise data on the relative position between the system of Fig. 7 and the solar array B. A control unit 319 processes the data and provides operating commands for drive mechanism 320 and pistons 316 and 317. The system in Fig. 7 changes its horizontal, height and angular positions until profiles 2112 and 2113 are aligned with 112b and 113b, respectively (ie, rails 112 and 113 of solar row B). The start cleaning command is given and the cleaning system moves from profiles 2112 and 2113 to profiles 112b and 113b and the cleaning cycle of solar row B begins, as described in this document with reference to Figs. 1 - 6. The process described above can be repeated for any number of solar arrays.

[0097] The main advantage of the system and method of Fig. 7 is that a single cleaning system can clean multiple solar rows and, in turn, significantly reduce the cleaning cost per row. Furthermore, as the system is not stationary at a given location, it can provide more flexibility as long as the real estate space close to the rows is taken into account.

[0098] The embodiments of the invention described above provide several advantages. Among others, one or more of the modalities provide a system and method that will make cleaning the solar panel simple, efficient, and which could, optionally, not use water. In addition, a system and method are disclosed that will make the solar panel cleaning process automatic and cost-effective. Still additionally, a system for cleaning solar panels is provided which requires minimal maintenance and supervision with low cost construction. The invention also provides a solar panel cleaning system and method that could achieve high cleaning quality along with a high level of reliability in all climates and topographical conditions. The system is also adaptable to existing as well as newly built solar parks and solar installations.

[0099] It is to be understood that the present invention is not limited to the embodiments described above, but includes any embodiments within the scope of the following claims. While the invention has been described above with respect to specific apparatus and specific implementations, it should be clear that various modifications and changes can be made, and various features of one embodiment can be included in other embodiments, within the scope of the present invention. It should be understood that the present invention is not limited to the embodiments illustrated and described herein.

Claims (20)

1. Waterless solar panel cleaning system for cleaning solar panels from a solar row (111), said solar row having a length and a width and being slanted and having an upper end and a lower end in a width direction of the said solar array, said upper end being raised to a higher position than said lower end, characterized in that said system comprises: at least one waterless cleaning apparatus (124) which is selectively operable to clean the solar panel surface of said solar array without using water; a support frame supporting said at least one waterless cleaning apparatus, said support frame being configured to selectively move said at least one waterless cleaning apparatus in both said width direction and said length direction on a surface of said solar array; and a controller (120) coupled to said at least one waterless cleaning apparatus and said support frame to selectively move said at least one waterless cleaning apparatus in said length direction of said solar row, and to selectively stop moving said at least one waterless cleaning apparatus up and down in said width direction of said solar row, between said upper and lower ends, and causing said at least one waterless cleaning apparatus to clean without watering said solar panel surface of said solar row during a downward movement of said at least one waterless cleaning apparatus in said width direction of said solar row, wherein said at least one waterless cleaning apparatus comprises at least an air flow creating apparatus which creates a directional air flow flowing in said width direction of said solar array so that the said air flow pushes dust particles on said solar panels by an inclination and away from said solar panels without using water, said at least one air flow creating apparatus comprising: flexible fins (140) which move in a direction (141) of said air flow and touching said solar panels to increase the cleanliness of said solar panels by said air flow; and at least one rotating cleaning apparatus which creates said downward air flow along said surface of said inclined solar panel. A system according to claim 1 for cleaning solar panels from a plurality of solar rows being parallel to each other, comprising: a movable frame (136) which is movable in a direction perpendicular to said length direction of said plurality of solar arrays; characterized in that said system further comprises: a drive mechanism (117) for driving said movable frame to a position in alignment with one near said plurality of solar arrays, so that said by at least one waterless cleaning apparatus is operable to clean said solar panels from said next solar row, without using water, wherein said at least one waterless cleaning apparatus is mounted on said movable frame. 3. System according to claim 2, characterized in that said movable frame comprises an adjustment system for aligning said at least one waterless cleaning apparatus with solar panels of a solar row to be cleaned. 4. System according to claim 3, characterized in that said adjustment system comprises a mechanism for at least one of selectively elevating, lowering and/or tilting said at least one waterless cleaning apparatus to align with a solar row to be cleaned. 5. System according to claim 4, characterized in that said movable frame comprises a controller receiving inputs from a measuring device to cause said drive mechanism to position said at least one cleaning apparatus no water to align with the solar panels of a solar row to be cleaned. 6. System according to claim 2, characterized in that it further comprises at least one guide on which said movable frame is movably mounted, said at least one guide extending perpendicular to said length direction of said plurality of solar rows, said movable frame being movable along said at least one guide in order to be successively in alignment with said plurality of solar rows to be cleaned. 7. System according to claim 1, characterized in that said flexible fins comprise a plurality of flexible fabric fins coupled to said at least one rotary cleaning apparatus. 8. System according to claim 7, characterized in that said plurality of flexible fabric fins is made from microfiber fabric. 9. System according to claim 7, characterized in that said plurality of flexible fins comprises a quick-connect mechanism (142, 143) for quickly connecting said plurality of flexible fabric fins to said at least one apparatus. rotary cleaning. 10. System according to claim 1, characterized in that said controller causes said at least one waterless cleaning apparatus to move along the length direction of said solar row to a new position to start a new waterless cleaning cycle. 11. System according to claim 1, characterized in that said support frame comprises: a main frame (114) which is movable along the length direction of said solar row; and a secondary frame (136) which is movable along said main frame in said width direction of said solar row, said secondary frame comprising said at least one waterless cleaning apparatus, said at least one waterless cleaning apparatus. water being operable to clean said surface of said row of solar panel without using water while said secondary frame moves in said main frame in said width direction of said row of solar panel from said upper end of said row of panel towards said lower end of said row of solar panel. 12. System according to claim 11, characterized in that it comprises a winch (80) with at least two cables (131), and wherein said winch connects said main frame and said secondary frame, so that the rolling and releasing of a winch cable causes an upward and downward movement of said secondary frame, respectively, with respect to said main frame. System according to claim 12, characterized in that each of said at least two cables has a conductive section, and said at least two cables move said secondary frame up and down while electricity is transferred. through said conducting section of said at least two cables to cause said at least one waterless cleaning apparatus to rotate and clean said surface of said row of solar panel without using water during the downward movement of said at least one apparatus cleaning without water. System according to claim 13, characterized in that said at least two cables are connected to two opposite sides of a winch cylinder (130) and to a center of an upper section of said secondary frame to create a angle between said at least two cables which allows orderly rolling of said at least two cables inside and outside said winch cylinder. System according to claim 13, characterized in that said at least two cables are connected to a center of said winch and to two opposite sides of an upper section of said secondary frame to create an angle between said by at least two cables which allows orderly rolling of said at least two cables into and out of said winch cylinder. 16. System according to claim 12, characterized in that it comprises an electric motor (118) that drives said winch while said secondary frame moves upwards and said same motor operates as a braking generator that controls a speed of said secondary frame when it moves down. The system of claim 16, characterized in that energy generated by said engine during operation as said brake generator is coupled to charge at least one battery (119) of said system. The system of claim 7, characterized in that said at least one rotating cleaning apparatus comprises a conveyor belt (224) to which said plurality of flexible fabric fins is attached. 19. The system of claim 18, characterized in that said plurality of flexible fabric fins attached to said conveyor belt are arranged to produce said directional air flow and to touch and clean said solar panel surface while moving down along a slope of said solar panel. 20. The system of claim 18, wherein said plurality of flexible fabric fins comprises a quick-connect mechanism for quickly connecting said plurality of flexible fabric fins to said conveyor belt.

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