Patent Application
20200336101
The disclosure is directed to photovoltaic or solar panels, and particularly to methods for cleaning the panels.
The conversion of sunlight into electricity, i.e., solar power, continues to be a popular source of energy. Solar cell or panel arrays may include a few or thousands of solar cells and panels that are positioned on or near buildings or across large tracts of land. The performance of such solar cell and panel arrays may be diminished substantially because of snow, ice, or dust which decreases the ability of the solar cells to receive sunlight.
If snow, ice, or dust accumulate on the solar cells and panels, the sunlight may be prevented from reaching the solar cells thereby preventing the solar cells from generating power until the snow or ice melts or the dust is removed. In certain regions, there may be several sunny days after snow or ice storms, but the accumulation of snow or ice that does not melt, prevents the solar panels from operating normally.
Certain prior solar cell cleaning methods and apparatus use water to clean the solar panels. This approach is not practical when there is snow and/or ice or for solar panels installed in the desert. Other approaches have used electrostatic fields to repel dust or the creation of air-flow over the surface of the solar panels. While these or other prior solar cell cleaning methods and apparatus have been proposed, there still remains a need for an improved method for cleaning solar cells and panels particularly when snow, ice, or dust accumulate on the solar panels thereby reducing or eliminating the electrical output.
The present invention relates to methods for cleaning solar panels and reducing power consumption during the cleaning of snow, ice, or dust from solar panels. By using the disclosed methods with larger solar panel arrays, the power consumption for cleaning may be reduced to a relatively small amount that may be produced in whole or in part by the solar panels.
The methods of the present invention remove snow, ice, or dust from obstructed solar panels by using either heated cleaning devices; electromagnetic/electrostatic cleaning devices; or combination devices which provide both heating and electromagnetic/electrostatic outputs. Sensors determine when the solar panels are obstructed to an unacceptable level by snow, ice, or dust thereby preventing the panels from generating a normal electrical output. Depending on the kind and location of the obstruction, groups of selected and heated cleaning devices are activated to melt snow and ice or groups of selected electromagnetic/electrostatic cleaning devices are activated to remove dust. The groups of cleaning devices are incrementally and sequentially activated until the surfaces of the solar panel array are clean.
In accordance with the methods of the present invention, only a portion, i.e., as few as one, of the cleaning devices, from the selected group of solar panels, are initially (first) activated when the solar panels are obstructed by snow, ice, or dust. Thereafter, when the first selected solar panel(s) are cleared of obstruction, a second group of obstructed solar panels, i.e., as few as one, are incrementally and sequentially selected, and the cleaning devices associated with those subsequently selected solar panels are activated.
The method of incrementally and sequentially selecting obstructed solar panels, and activating the cleaning devices for the selected solar panels, continues until the entire solar panel array is cleaned. The cleaning devices for the incrementally and sequentially selected obstructed panels may be powered by the prior solar panels that have been cleaned. Thus, the electrical power generated by the cleaned solar panels is used in whole or in part to power the cleaning devices for the next group of selected, obstructed solar panels.
The sensors are used to detect information such as the location, size, and type of obstruction on the solar panels. This information and other information are evaluated by a controller before selecting cleaning locations on the solar panel array and before activating the selected cleaning devices. The controller evaluates information including the power output of the solar panels; information from the sensors regarding the type and location of the obstruction; the date, time, and temperature; and the current weather conditions and weather forecasts.
The collected information is processed by the controller for the purposes of determining: the type and extent of the obstruction; a location for the cleaning area where one or more of the cleaning devices are activated; and the type of cleaning device to be used for removing the obstruction.
These and other aspects of the present invention will be understood from the following detailed description of the embodiments and appended claims with the drawings.
Reference will now be made to the drawings where embodiments of the methods of the present invention are illustrated. It will be apparent to one of ordinary skill in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. It is intended that the present invention covers such modifications and variations as exist within the scope of the appended claims and their equivalents.
The present invention provides methods to improve photovoltaic (solar) cell performance.
As schematically shown in
As is known, the performance of individual solar panels, groups of solar panels, or solar panel arrays, may be diminished because of snow, ice, or dust which decreases the ability of the solar cells to receive sunlight. While there have been prior disclosures of cleaning apparatus for solar panels, there remains a need for an improved method for cleaning solar cells while minimizing the amount of power required to operate the cleaning method or apparatus.
Referring to
Another embodiment of self-cleaning device 80 is illustrated in
As previously described, and now more particularly described in connection with
Referring to
A controller 110 receives information from the sensors 100 and also receives other information including weather conditions, weather forecasts, and information relating to time, date, and temperature. The collection of information is evaluated by the controller 110.
If the collection of information evaluated by controller 110 results in a determination that snow or ice accumulation obstructs some or all of the solar panels 50, controller 110 generates a command signal that is sent to snow and ice controller 130. Controller 130 activates the electrodes 82 or heating elements 90 for one or more selected solar panels for melting the snow or ice obstruction from the selected panels.
If the collection of information processed by controller 110 results in a determination that dust or dirt obstructs some or all of the solar panels, controller 110 generates a command signal that is sent to dust controller 120. As shown schematically in
As shown in
As described previously, the methods of the present invention use heated cleaning devices 90 and/or multi-functional cleaning devices 82 for removing snow, ice, or dust from solar panels 50. In accordance with the methods of the present invention, an initial group of obstructed solar panels are selected for cleaning. The cleaning devices (either 90 or 82) for the initial group of solar panels are used to remove snow, ice, or dust from the selected solar panels. After the initially selected obstructed solar panels are cleaned, the power generated by the cleaned solar panels provides power for operating the cleaning devices for the next group of selected obstructed solar panels.
As described previously, the sensors 100 are used to detect information such as the type, location, and size of obstruction. The information gathered by the sensors 100 is transmitted to the controller 110.
The controller 110 evaluates information including the power output of the array of solar panels compared to the normal threshold level; the sensor detection information; information regarding the date, time, and temperature; and information regarding the weather conditions and weather forecasts. Sensors 100 are not activated until the power output of the array of solar panels falls below the array's normal operating or threshold level.
The collection of gathered information is processed by the controller 110 for the purpose of determining when to activate one or more of the cleaning devices and where to activate one or more of the cleaning devices. An initial cleaning location, having obstructed solar panels, is selected, and a group of cleaning devices for those obstructed solar panels are selected. The selected cleaning devices, in the selected cleaning location, are then activated to remove the obstruction from the selected group of obstructed solar panels.
After the initial selected group of obstructed solar panels is cleaned, new groups of obstructed solar panels are incrementally and sequentially selected and then cleaned.
A purpose for selecting the initial cleaning location is to make the cleaning process more efficient. If, for example, the obstruction does not cover the entire array of solar cells, it is more efficient to first activate cleaning devices at cleaning locations that are obstructed. Alternatively, if the obstruction covers most or all of the solar panel array, the cleaning location may be the entire solar panel array, and the controller 110 would initially select a first group of obstructed solar panels; activate the cleaning devices for the first group of obstructed solar panels until the first group is cleared of obstruction; and then incrementally and sequentially select and activate subsequent groups of cleaning devices in cleaning locations on the solar panel array that still have obstruction.
After the first group of solar panels are cleaned of snow, ice, or dust, a second group of obstructed solar panels are selected and cleaned by using, at least in part, the power being generated by the first group of cleaned solar panels. A second group of obstructed solar panels is selected and thereafter, incrementally and sequentially, additional groups of obstructed solar panels are selected. The cleaning devices for those incrementally and sequentually selected groups of obstructed solar panels are activated. The method of cleaning obstructed solar panels, as described herein, continues until the entire array of solar panels is cleaned.
The present invention may be embodied in other forms without departing from the spirit and the attributes thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicative of the scope of the invention.
