Abstract:
According to some embodiments, systems and or methods may be provided to transport electrical energy from a first location having an electrical energy source to a second location, remote from the first location and having a load to accept electrical energy. A first pipeline between the first and second locations may include a first chamber containing a cathodic fluid. A second pipeline between the first and second locations may include a second chamber containing an anodic fluid, and at least of a portion of said first and second pipelines include a contiguous area. A membrane may separate the cathodic and anodic fluids at said contiguous area to exchange electrical energy between said fluids and create an electrochemical storage cell across said membrane. By utilizing additional alternating layers of said electrolyte, casing and membrane multiple cells may be created.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims the benefit of U.S. Provisional Application No. 61/238,535 entitled “System for Storing and Transporting Electrical Energy”, filed Aug. 31, 2009. 
     
    
     FIELD 
       [0002]    The present invention relates to storing and/or transmitting electrical energy. In particular, some embodiments of the present invention are directed to storing and/or transporting electrical energy in connection with cathodic and anodic fluids. 
       BACKGROUND 
       [0003]    Many of the renewable energy generation systems proposed, built, and utilized today generate power inconsistently, far from locations where it is needed and out of sync with demand. Many of these existing energy generation plants, including those with non-renewable sources, cannot efficiently change output to match demand fluctuations, so additional generators must either be turned on at a moment&#39;s notice or generate unused power during periods of reduced demand. Current technology relies on overhead high voltage transmission lines to transport electrical energy. Voltage fluctuations, system inconsistencies and inefficiencies cost the U.S. an estimated 119 billion dollars per year. Efforts being made to modernize the system into a “smart grid” are adding control, metering and monitoring capabilities, but do not change the fundamental problem of the overhead transmission line concept; namely the instantaneous nature of transport and inability to store large quantities of power. Another problem with overhead transmission lines is that construction of new lines is often challenged due to the environmental and aesthetic impact of these lines. 
         [0004]    A variety of intermittent electrical energy storage systems have been proposed and are being utilized on a small scale, but, to date, none of these systems have won wide acceptance. An example of such a storage system is the flow battery design described in U.S. Pat. No. 3,996,064. This system utilizes two rectangular tanks containing vanadium electrolytes, separated by a membrane. Oppositely charged electrodes are inserted into each tank to charge and discharge. While this system may be capable of efficiently storing electrical energy it is only accessible at a single location and it does not allow for energy transportation. 
         [0005]    Therefore, it may be advantageous to provide improved systems and methods to store and/or transport electrical energy in a manner that allows for relatively quick and efficient transportation over relatively great distances. 
       SUMMARY 
       [0006]    To alleviate these problems, some embodiments of the present invention introduce systems and methods of storing and/or transmitting electrical energy in connection with cathodic and/or anodic fluids separated by a membrane. 
         [0007]    This invention may, for example be used for some or all of the following three purposes: 
         [0008]    1. To transport power from point A to point B and to points in between A and B 
         [0009]    2. To store excess power. 
         [0010]    3. To absorb and store power surges. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is system  100  according to some embodiments of the present invention. 
           [0012]      FIGS. 2  A and B illustrate a portion of an energy pipeline according to some embodiments of the present invention. 
           [0013]      FIG. 3  A through C provides detailed views of a portion of the present invention in an embodiment that utilizes concentric chambers and a circular membrane. 
           [0014]      FIG. 4  A through C provide detailed views of a portion of the present invention in an embodiment that utilizes a bisecting membrane. 
           [0015]      FIG. 5  illustrates an embodiment wherein the fluids are stationary throughout the pipeline portion of the present invention. 
           [0016]      FIG. 6  illustrates an embodiment wherein the fluids are charged using electrodes placed directly into the pipeline portion and the fluids are circulated throughout the present invention 
           [0017]      FIG. 7  illustrates an embodiment wherein the fluids are charged using electrodes in separate chambers and then circulated throughout the present invention. 
           [0018]      FIG. 8  illustrates an embodiment wherein the fluids are charged using electrodes in membrane separated chambers and then circulated throughout the present invention. 
           [0019]      FIG. 9  is a flow diagram illustrating a method of storing and/or transporting electrical energy in accordance with some embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Referring now to the drawings,  FIG. 1  is system  100  according to some embodiments of the present invention. The system  100  includes an energy generation power source  110  coupled to an apparatus  120  for storing and/or transporting electrical energy. The apparatus  120  may also be coupled to an existing conventional power grid  130  for integration into the current system. 
         [0021]    Moreover, the apparatus  120  may be coupled to intermediate usage sites, grid connectors, and/or additional power generation sites  135 . This allows the system to transport energy to multiple locations, rather than simply allowing a two-way flow. Further, the apparatus  120  may be coupled to additional energy generation power sources  140 , such as solar or wind sources, adding additional power. Finally, the apparatus  120  may be coupled to an energy usage site  150 . Thus, the apparatus  120  may facilitate the storage and/or transport of electrical energy in accordance with any of the embodiments described herein. These transport distances may be on the order of miles. 
         [0022]    For example,  FIG. 2  illustrates a portion of an energy pipeline  200  in accordance with some embodiments of the present invention. In particular, the pipeline  200  may comprise an outer casing  210 . The outer casing  210  is preferably made of a material that does not interact with the electrolytes contained in chambers  220  and  230 . This outer casing may be surrounded by insulation (not shown in  FIG. 2 ). Outer chamber  220  contains one of the two electrolytes (anodic or cathodic), while inner chamber  230  contains the other. The outer chamber  220  is defined as the area between the outer casing  210  and the membrane  240 . The inner chamber  230  is defined as the volume within the membrane  240 . The two chambers are divided by membrane  240 , which is shaped as a tube. The cylinders of the chambers  220  and  230  are concentric. The radii of the two chambers may be sized so that the volume of chamber  220  is equal to the volume of chamber  230  and the ratio of electrolyte to membrane  240  may maximize efficiency. The radii of the entire system may be adjusted for transportation distances and volume of power storage and transport needed. Within the inner chamber is electrode  251  and within the outer is electrode  252 . Electrode  252  is preferably circular and is inserted into the outer chamber without contacting membrane  240 . Electrode  251  may be shaped so as to maximize surface area in contact with electrolyte and may extend into the chamber  230  for a distance that maximizes efficiency. Electrode  251  may be installed in the inner chamber  230  without contacting the membrane  240 . Electrode  252  may be shaped so as to maximize surface area in contact with electrolyte and extend into the chamber  220  for a distance that maximizes efficiency. Both electrodes  251  and  252  may be sized so as to have equal surface area. Electrodes may be utilized at the power supply end of the invention to transfer energy from the electrical source to the electrolyte and at the other end of the system to transfer energy from the electrolyte to the grid or use apparatus. Insulated wires  260  may be attached at the ends of the electrodes  250  and may conduct electricity without contacting the membrane  240  or outer casing  210 . Insulated wires  260  are utilized to transfer electricity to and from the electrodes. Switches, meters and limiting diodes, regulators, etc.,  270  are used to regulate, measure and control the flow of power, and are attached to the insulated wires  260  coming from the power source and going to the grid or power use. Additional layers of electrolyte, membrane and casing may be used to create multiple cells. 
         [0023]      FIG. 3  is a detail of energy pipeline  300  as described in  FIG. 2 , wherein a possible intermediate discharge site is illustrated. The inner chamber  330  may be filled with one electrolyte, and the outer chamber  320  may be filled with the other, with one electrolyte being cathodic and the other anodic. The two chambers may be concentric cylinders. They may be separated by an inner casing  340  which is preferably made of a material non-reactive with the electrolytes. This casing material may be perforated and the perforations covered with sections of membrane  341 . Alternately, the inner casing may be perforated and then coated with membrane, with the non-reactive substance serving as a frame that preserves the cylindrical structure of the membrane. The inner casing may be further supported with the use of struts or fins  380 . The struts or fins  380  may protrude through the outer chamber  320  and may be connected to the outer casing  310 . The outer casing  310  may surround the entire structure and prevent interaction of the electrolytes with the outside environment, including temperature-related insulation (not shown in  FIG. 3 ). The electrode  351  into the inner chamber  330  may be made of carbon or another conductor. The section of the inner electrode  351  that travels through the outer chamber  320  may be coated with non-conducting insulation, thus preventing electrical interference. The outer electrode  352  may be inserted through the outer casing  310  into the outer chamber  320  and the electrolyte contained therein. These electrodes may be inserted into a middle section of the transportation pipeline and utilized at intermediate discharge stations. In the event that the structure is used aboveground, support pads  390  may be added to stabilize the structure. 
         [0024]      FIG. 4  is a detail of energy pipeline  400  as described in  FIG. 2 , wherein a possible intermediate discharge site is illustrated. However, in this embodiment, the chambers may be semicircular prisms, and the membrane is preferably vertical, but may be constructed at a different angle. This structure may consist of a chamber  420  and a symmetrical chamber  430 . The chambers each may occupy half of the volume of the pipeline  400 . Chamber  430  and chamber  420  may be divided by a membrane  440  that may be a diameter of a cross-section of the pipeline  400 . The outer casing  410  may contain the chambers and membrane. Outer casing  410  is preferably constructed of a material non-reactive with the electrolytes, and may include any insulating materials necessary. Electrodes  450  may be inserted on either side of membrane  440 , and may be constructed in any functioning geometry so long as they are in contact with electrolytes contained in the chambers  420  and  430 . The membrane  440 , particularly if it is not strong enough to support its own structure, may be broken into smaller pieces  441  and may be inserted along a supporting framework  442  which may be constructed from a non-interacting material. If the pipe is used above ground, support pads  490  may be added to prevent movement. 
         [0025]      FIG. 5  illustrates a structure  500  wherein the electrolytes may be charged while in a pipe, but a standard flow battery setup may be used for discharge. Pipelines  510  and  515  may be filled with electrolyte, with one containing the cathodic fluid  525  and the other containing anodic fluid  526 . The two lines may be kept separate when charged. They are shown for clarity as separate pipelines, but may also be constructed in a concentric fashion with a non-conducting casing between the two chambers. Regulating equipment  570  controls the flow of electricity into the pipes from the power source. Electrodes  551  from the power source may be inserted directly into the pipes for charging. Energy disperses throughout the electrolyte. At the other end of the line, the electrolytes may sit in two chambers, with chamber  520  filled with one of the two electrolytes (anodic and cathodic) and  530  filled with the other. The two chambers may be separated by a membrane  540 . Electrodes  552  located in each chamber may facilitate discharge. Again, flow of electricity out of the system may be regulated by switching and metering equipment  570 . The capacity of the system may be expanded by the addition of electrolyte storage chambers  580 . Pressure, temperature, and other fluid flow monitoring equipment may be utilized within the system (not shown). 
         [0026]      FIG. 6  illustrates a structure  600  that is similar to the structure  500 , excepting that the fluid in the structure in  FIG. 6  may be in motion and that in  FIG. 5  may not be. First, voltage regulators and various switching and metering equipments  671  may regulate the flow of electricity into the main pipes. Pipeline  610  may be filled with a fluid containing one of the two electrolytes  625 , and pipeline  615  may be filled with the other, electrolyte  626 . Electrodes from the power source  650  may charge these fluids, and may be added at the end of the pipe or at intermediate locations. The fluids in the pipes may be moved by pumps  690  at intermediate locations and again during removal from the pipes. Once removed from the pipes, they may enter a traditional flow battery setup, wherein cells containing two electrolyte chambers  620  and  630  divided by a membrane  640  may be charged or discharged. Here, they are preferably discharged only, with the flow of electricity preferably regulated by switching and metering equipment  672 . After discharge, the electrolyte may be pumped back to the charging station where it may be recharged to complete the cycle. For example, where the power generation source is solar, the charged electrolyte from the solar power generation site might be pumped to the demand site during the day and then at night the direction of flow reversed and the discharged electrolyte pumped from the demand site back to the generation site. Where used in a system with sporadic energy production the electrolyte might be stored in chambers  680  at either end until needed. If electrolytes are used that cannot be mixed, they might be pumped and stored separately. In the case of electrolytes that can be mixed, there might need to be only one pipe in each direction or in one of the two directions. An advantage of such embodiments may be that the membrane can be maintained and replaced without significantly disturbing the pipeline components of the system. Pressure, temperature, and other fluid flow monitoring equipment may be utilized within the system (not shown). 
         [0027]      FIG. 7  illustrates structure  700 , wherein the electrolytes may be charged individually using electrodes  750  inside of charging tanks. The flow of electricity into the system may be regulated by switches, limiting diodes, and metering equipment  771 . Then, the cathodic and anodic electrolytes  725  and  726  may be moved with pumps  790  through pipelines  710  and  715 . The fluids may then be pumped into two chambers  720  and  730  separated by a membrane  740 . Electrodes  750  may be used to discharge the fluids, and the flow of electricity to grid or use may be regulated by switches, limiting diodes, and other metering equipments  772 . The discharged fluids may then pumped through either a pipe for discharged electrolytes or two separated discharge pipes  716  and  717 , and the cycle may be repeated. In this embodiment the electrolyte may be circulated continuously and/or stored in chambers  780 . Pressure, temperature, and other fluid flow monitoring equipment may be utilized within the system (not shown). 
         [0028]    Structure  800  in  FIG. 8  is similar to structure  700 , excepting that structure  800  may be charged through a standard flow battery setup. Here, the flow of electricity into the system is regulated by switches and meters  871 . The electrolytes may be charged using a standard redox-flow battery, in which electrodes  850  are inserted into chambers  821  and  831 . Each chamber may be filled with an electrolyte-containing liquid  825  and  826 , with the two chambers having opposite charges. The two chambers  821  and  831  may be divided by a membrane  841 . To change the speed of charging, multiple cells may be used. Pipelines  810  and  815  may be filled with liquids containing electrolytes of opposite charges, corresponding to the liquids in the two chambers. Fluids may be transferred from the chambers to the pipes using pumps  890 . They may then travel through the pipe to a setup that is preferably identical to the charging assembly. At the discharge station, however, current may be removed rather than added to the system. Two electrolyte chambers  822  and  832  may be filled with the oppositely charged electrolytes  825  and  826 . Electrodes  850  may be inserted into them, and switches and meters  872  may regulate the flow of current. This cell may be replicated as needed. After discharge, electrolytes may be pumped or transported back to the charging station through pipelines  812  and  817 . The process may be repeated or run continuously. Charged and/or discharged electrolyte may be stored in chambers  880 . Pressure, temperature, and other fluid flow monitoring equipment may be utilized within the system (not shown). 
         [0029]      FIG. 9 . Is a flow diagram  900  illustrating a method of storing and/or transporting electrical energy in accordance with some embodiments. The flow chart described herein does not imply a fixed order to the steps, and embodiments of the present invention may be practiced in any order that is practicable. At  910 , energy is received by the system. At  920 , the energy is used to charge cathodic and anodic fluids. At  930 , the energy is transported to a remote location. At  940 , the energy is stored for as long as is needed, before, after, or during this period of transportation. At  950 , the energy is discharged. At  960 , energy is provided to the grid or directly to demand. 
         [0030]    Thus, some embodiments of this invention may store electricity in a manner that allows for relatively quick and efficient transportation over relatively great distances. By combining electrical energy transmission and storage into a single system, this invention will reduce operating costs and enable increased use of renewable energy sources. Through absorption and storage of electrical energy at multiple locations, some embodiments of the present invention may act as a buffer for the current power grid, absorbing excess power and/or surges and storing the energy for future use. Furthermore, depending on topographical, environmental, geological and political conditions the system may be built as a pipeline following existing design and engineering criteria and either be suspended from support pads or buried underground, substantially reducing the aesthetic and environmental impact of the electrical transmission grid. 
         [0031]    The preceding illustrates various additional embodiments of the present invention. These do not constitute a definition of all possible embodiments, and those skilled in the art will understand that the present invention is applicable to many other embodiments. Further, although the following embodiments are briefly described for clarity, those skilled in the art will understand how to make any changes, if necessary, to the above-described apparatus and methods to accommodate these and other embodiments and  applications. 
         [0032]    Although particular configurations of the present invention have been described with respect to various elements provided herein, it will be appreciated that many other variations on the above could be constructed in addition, such as a rectangular pipe or membranes with internal support structures. Although certain materials listed herein could be used, such as PVC piping for the outer casings of various pipes, or vanadium for the electrolyte, other materials may also be used. 
         [0033]    The present invention has been described in terms of several embodiments solely for the purpose of illustration. Persons skilled in the art will recognize from this description that the invention is not limited to the embodiments described, but may be practiced with modifications and alterations limited only by the spirit and scope of the appended claims.