Systems, vehicles, and methods for maintaining rail-based arrays of photovoltaic modules

Abstract

A system includes an elongated rail including support surfaces and a mounting surface disposed between the support surfaces. Photovoltaic modules can be coupled to the mounting surface and raised relative to the support surfaces. A first maintenance vehicle can include a cleaning head, actuator, motor, and support legs. The support legs can suspend the cleaning head over the photovoltaic modules and can be respectively movably coupled to the support surfaces so as to laterally and sequentially move the cleaning head parallel to the elongated rail and across each of the photovoltaic modules responsive to actuation of the motor. At least a portion of the cleaning head can be vertically movable between a disengaged position spaced apart from the photovoltaic modules and an engaged position in contact with at least one of the photovoltaic modules responsive to actuation of the actuator.

What is claimed: 
     
         1 . A method for maintaining photovoltaic modules, the method including:
 providing a first elongated rail including first and second support surfaces and a first mounting surface disposed between the first and second support surfaces, a first array of the photovoltaic modules being coupled to the first mounting surface and raised relative to the first and second support surfaces;   disposing a first maintenance vehicle on the first and second support surfaces, the first maintenance vehicle including a first cleaning head, a first actuator, a first motor, and first and second support legs;   suspending the first cleaning head over the photovoltaic modules of the first array using the first and second support legs, the first and second support legs being movably coupled to the first and second support surfaces so as to laterally and sequentially move the first cleaning head in a direction parallel to the first elongated rail and across each of the photovoltaic modules of the first array responsive to actuation of the first motor; and   moving at least a portion of the first cleaning head between a disengaged position spaced apart from the photovoltaic modules of the first array and a first engaged position in contact with at least one of the photovoltaic modules of the first array responsive to actuation of the first actuator,   the first and second support legs each including a joint, the first actuator automatically increasing or decreasing an angle of the joint such that a relative angle between the first maintenance vehicle and each of the photovoltaic modules is adjusted according to a tilt of that photovoltaic module.   
     
     
         2 . The method of  claim 1 , the first cleaning head including a second motor, the at least a portion of the first cleaning head including a brush contacting at least one of the photovoltaic modules of the first array when the first cleaning head is in the first engaged position responsive to actuation of the first actuator, the method further including rotating the brush along an axis parallel to the photovoltaic modules of the first array responsive to actuation of the second motor. 
     
     
         3 . The method of  claim 2 , the first cleaning head further including a wiper, the wiper contacting at least one photovoltaic module of the first array when the at least a portion of the first cleaning head is in the first engaged position, the method further including at least partially wiping the at least one photovoltaic module of the first array via the contact with the wiper. 
     
     
         4 . The method of  claim 1 , wherein the first and second support legs respectively are movably coupled to the first and second support surfaces by first and second wheels that respectively contact and rotate along the first and second support surfaces. 
     
     
         5 . The method of  claim 1 , further including a second elongated rail including third and fourth support surfaces and a second mounting surface, a second array of the photovoltaic modules being coupled to the second mounting surface and raised relative to the third and fourth support surfaces. 
     
     
         6 . The method of  claim 1 , wherein at least one of the first and second support legs is adjustable so as to accommodate photovoltaic modules at different angles than one another. 
     
     
         7 . The method of  claim 1 , the first maintenance vehicle further including a trimmer mechanism to remove vegetation. 
     
     
         8 . A system for maintaining photovoltaic modules, the system including:
 a first elongated rail including first and second support surfaces and a first mounting surface disposed between the first and second support surfaces, a first array of the photovoltaic modules being coupled to the first mounting surface and raised relative to the first and second support surfaces; and   a first maintenance vehicle disposed on the first and second support surfaces, the first maintenance vehicle including a first cleaning head, a first actuator, a first motor, and first and second support legs,   the first and second support legs suspending the first cleaning head over the photovoltaic modules of the first array and being movably coupled to the first and second support surfaces so as to laterally and sequentially move the first cleaning head in a direction parallel to the first elongated rail and across each of the photovoltaic modules of the first array responsive to actuation of the first motor,   at least a portion of the first cleaning head being movable between a disengaged position spaced apart from the photovoltaic modules of the first array and a first engaged position in contact with at least one of the photovoltaic modules of the first array responsive to actuation of the first actuator,   the first and second support legs each including a joint, the first actuator automatically increasing or decreasing an angle of the joint such that a relative angle between the first maintenance vehicle and each of the photovoltaic modules is adjusted according to a tilt of that photovoltaic module.   
     
     
         9 . The system of  claim 8 , the first cleaning head including a second motor, the at least a portion of the first cleaning head including a brush movable to contact at least one of the photovoltaic modules of the first array in the first engaged position responsive to actuation of the first actuator, the brush further being rotatable along an axis parallel to the photovoltaic modules of the first array responsive to actuation of the second motor. 
     
     
         10 . The system of  claim 9 , the first cleaning head further including a wiper, the wiper being in contact with the at least one photovoltaic module of the first array when the at least a portion of the first cleaning head is in the first engaged position and operable to at least partially wipe the at least one photovoltaic module. 
     
     
         11 . The system of  claim 8 , wherein the first and second support legs respectively are movably coupled to the first and second support surfaces by first and second wheels that respectively contact and rotate along the first and second support surfaces. 
     
     
         12 . The system of  claim 8 , further including a second elongated rail including third and fourth support surfaces and a second mounting surface, a second array of the photovoltaic modules being coupled to the second mounting surface and raised relative to the third and fourth support surfaces. 
     
     
         13 . The system of  claim 8 , wherein at least one of the first and second support legs is adjustable so as to accommodate photovoltaic modules at different angles than one another. 
     
     
         14 . The system of  claim 8 , the first maintenance vehicle further including a trimmer mechanism to remove vegetation. 
     
     
         15 . A system for maintaining photovoltaic modules, the system including:
 a first elongated rail including first and second support surfaces and a first mounting surface disposed between the first and second support surfaces, a first array of the photovoltaic modules being coupled to the first mounting surface; and   a first maintenance vehicle disposed on the first and second support surfaces, the first maintenance vehicle including a first cleaning head;   at least a portion of the first cleaning head being movable between a disengaged position spaced apart from the photovoltaic modules of the first array and a first engaged position in contact with at least one photovoltaic module of the first array,   the first cleaning head including:
 a brush; and 
 a wiper; 
   the at least a portion of the first cleaning head including the brush movable to contact the at least one photovoltaic modules of the first array in the first engaged position,   the wiper being in contact with at least one photovoltaic module of the first array when the at least a portion of the first cleaning head is in the first engaged position and operable to at least partially wipe the at least one photovoltaic module of the first array, and   the at least a portion of the first cleaning head further being movable to a second engaged position in which the brush contacts at least one photovoltaic module of the first array and the wiper does not contact the first array.   
     
     
         16 . The system of  claim 15 , the first maintenance vehicle including a first motor and first and second support legs, the first and second support legs suspending the first cleaning head over the photovoltaic modules of the first array and being movably coupled to the first and second support surfaces so as to laterally and sequentially move the first cleaning head in a direction parallel to the first elongated rail and across each of the photovoltaic modules of the first array responsive to actuation of the first motor. 
     
     
         17 . The system of  claim 15 , the first cleaning head further comprising a fluid reservoir, the first cleaning head being operable to dispense fluid from the fluid reservoir onto the at least one photovoltaic module of the first array. 
     
     
         18 . The system of  claim 15 , wherein the first and second support legs respectively are movably coupled to the first and second support surfaces by first and second wheels that respectively contact and rotate along the first and second support surfaces. 
     
     
         19 . The system of  claim 15 , further including a second elongated rail including third and fourth support surfaces and a second mounting surface, a second array of the photovoltaic modules being coupled to the second mounting surface and raised relative to the third and fourth support surfaces. 
     
     
         20 . The system of  claim 19 , further including a row-to-row mechanism configured to move the first maintenance vehicle from the first elongated rail to the second elongated rail.