Abstract:
A system including an irrigation system and a solar power assembly coupled to the irrigation system. Solar energy is received. The solar energy is utilized to charge at least one battery. The battery then provides power from the at least one battery to an irrigation controller.

Description:
BACKGROUND  
       [0001]     Irrigation systems, such as underground sprinkler systems, provide a time saving and convenient way to water lawns, landscaping, vegetation, and the like. A user simply programs the irrigation system to water a particular area at a particular time and then gives watering no more thought.  
         [0002]     A difficulty arises, however, when the user does not have power to operate the irrigation system. For instance, in the construction industry, builders often install underground sprinkler systems and landscaping prior to a development actually having electrical power. Thus, even though an irrigation system is in place, it can not be utilized to water the landscaping. Further, after a building project is completed, the owner of the development may not wish to immediately provide electrical power to it (e.g. if there is no tenant). Yet, the plant life still needs to be maintained. Accordingly, the owner of the development will either have to retain someone to manually water the landscaping or will have to provide electricity to the entire development solely to utilize the sprinkler system.  
         [0003]     Therefore, what is needed is an apparatus and method for powering an irrigation system through an alternate means, such as solar power.  
       SUMMARY  
       [0004]     In one embodiment, a system is provided. The system includes an irrigation system and a solar power assembly coupled to the irrigation system.  
         [0005]     In one embodiment, a method is provided. Solar energy is received. The solar energy is utilized to charge at least one battery. The battery then provides power from the at least one battery to an irrigation controller.  
         [0006]     In one embodiment, an apparatus is provided. The apparatus includes means for receiving solar energy, means for charging at least one battery with the solar energy, means for controlling an irrigation system, and means for providing power from the at least one battery to irrigation controlling means. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is functional block diagram depicting one example of an irrigation system including a solar power assembly. 
     
    
     DETAILED DESCRIPTION  
       [0008]     Referring to  FIG. 1 , in one example, an irrigation system  10  includes one or more valves irrigation zones  11 , one or more valves  12 , an irrigation controller  15 , and a solar power apparatus  16 .  
         [0009]     Irrigation zones  11  are the particular areas that irrigation system  10  waters. Typically, an irrigation zone  11  will include a plurality of sprinkler heads, pop-ups, or other water distribution devices that are connected by plumbing. The particular number of irrigation zones and the particular design of each irrigation zone depends on the environment in which irrigation system  10  is used. The configuration shown in  FIG. 1  is exemplary and provided for illustrative purposes only.  
         [0010]     Valves  12  control the flow of water to irrigation zones  11 . Typically each valve  12  includes an input  13  from a particular water source, such as a main line, and an output  14  that leads to the secondary lines, which feed a particular irrigation zone  11 . In one example, valves  12  are solenoid valves, which are actuated by an electrical signal sent from irrigation controller  15 . For instance, valves  12  could be of the kind that are actuated by receiving a 24 volts alternating current (VAC) signal from irrigation controller  15 . It should be noted, however, that these values are described for exemplary purposes only and that other valves sufficient to function in accordance with the operating principles described herein are intended to be encompassed by this disclosure.  
         [0011]     Irrigation controller  15  functions to actuate valves  12  by opening and closing them in accordance with user instructions. The instructions could be a predetermined watering schedule or could be a manual override. In one example, the irrigation controller  15  receives a 120 VAC operating input from the solar power apparatus  16  and outputs 24 VAC to valves  12 . The irrigation controller  15  in this example includes a built in transformer to down convert the input power of 120 VAC to 24 VAC.  
         [0012]     Solar power apparatus  16  powers irrigation system  10  through utilization of solar power. Solar power apparatus  16  in one example comprises at least one photovoltaic solar panel  17 , at least one battery  18 , a photovoltaic system controller (PSC), and a power inverter  22 .  
         [0013]     Solar panel  17  converts light from the sun into electricity and charges battery  18 . There number of solar panels  17  utilized in solar power apparatus  16  depends on the environment in which irrigation system  10  resides. For instance, in an area of minimal sunlight, an array of solar panels  17  may be necessary to provide sufficient power to charge battery  18 . In areas with a great deal of sunlight, only one solar panel  17  may be necessary to charge battery  18 . Similarly, the size and type of solar panels also depends on the environment in which irrigation system. For instance, a user, for aesthetic reasons, a user may want to use many small solar panels than one large big solar panel, or due to the location, the solar panel  17  may have to be roof mounted, ground mounted or pole mounted.  
         [0014]     In one example, solar panel  17  has 30 to 36 cells connected in series. Each cell produces about 0.5V in sunlight, so a 30 to 35 cell panel produces 15V to 18V. Solar panel  17  is mounted at the most effective angle to receive sunlight.  
         [0015]     Battery  18  in one example is a 12 volt (V) battery. Battery  18 , however, can be any battery suitable for use in a photovoltaic system. Examples include but are not limited to deep cycle nickel-cadmium and lead-acid batteries. Moreover, depending on the needs of the user, an array of batteries  18  can be used to power system  10 .  
         [0016]     PSC  20  in one example prevents battery  18  from overcharging. This is necessary because depending on the output of solar panel  17 , battery  18  could overcharge and then reverse current, thereby damaging solar panel  17 . For example, a 30 cell solar panel (15 V) can charge a 12 V battery without a controller, but it might not charge the battery completely. In contrast, a 36 cell solar panel (18 V) will charge battery  18  completely, but it will require a controller  10  to prevent overcharging. PSC may also include a discharge controller to prevent battery  18  from having an excessive discharge and thereby rendering system  10  powerless.  
         [0017]     Power inverter  22  receives DC power from battery  18  and converts it to VAC. In one example, power inverter  22  receives 12 VDC from battery  18  and converts it to 120 VAC. Power inverter sends the VAC power to irrigation controller  15 , which utilizes it to open and close valves  12  in accordance with the user&#39;s instructions.  
         [0018]     As stated earlier, the irrigation controller  15  in one example requires 120 VAC to operate and outputs 24 VAC to actuate valves  12 . This 24 VAC is not a constant draw but rather a short burst to open and close each valve  122 . A typical commercial system may have anywhere from 10 to 50 zones, but because there is no constant draw the system can accommodate many valves and zones.  
         [0019]     From a physical design standpoint, solar panel  17  should be mounted at the most effective angle to receive maximum sunlight in the environment in which the irrigation system  10  is present. For example, it might be necessary to install solar panel  17  on a roof, the ground, a pole, etc. The battery  18 , photovoltaic system controller  20 , and power inverter  22  can be mounted near the irrigation controller  15 , which is usually in a secure area, such as a building.  
         [0020]     The preceding description was provided for exemplary purposes only. There are many different variations of the system described above that are within the scope of the present disclosure. For example, there are many different sizes and types of solar panels  17  that can be chosen to fit the needs of a particular end user. One consideration when choosing the solar panel  17  will be amount of sunlight the particular area receives during a particular time of the year. It may be necessary to use multiple panels or an array of panels to generate sufficient power.  
         [0021]     Similarly, the photovoltaic controller  20  can be chosen according to the needs of the end user. An exemplary controller  20  will be equipped with terminals for the solar panel  17 , the battery  18 , and the load (inverter)  22 , and be rated for 12 V or 24 V systems. There are different controllers for different amp outages and thus the controller  20  should be sized for the systems peak power.  
         [0022]     The inverter  22  should also be sized according to the system. In one example, the inverter  22  will have a low battery shut down to prevent the battery from draining all the way, for example when there is are multiple cloudy days and the solar panel  17  can not provide enough charge.  
         [0023]     Batteries  18  should be chosen using location as a factor. If a climate or region does not have many sunny days or the time of year does not allow for multiple sunny days, multiple batteries  18  should be included in the system. For example, two 12V batteries could be wired together to increase the power to 24V (the other components would also be scaled up accordingly) and provide longer battery life.  
         [0024]     The matter set forth in the foregoing description and accompanying drawing is offered by way of illustration only and not as a limitation. While particular embodiments have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made without departing from the broader aspects of applicants&#39; contribution. The actual scope of the protection sought is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.