Abstract:
A device and a method for producing hydroelectric energy. The device generates compact-scale appreciable hydroelectric energy. Utilizing centrifugal force, at least one container attached to a radial arm moves horizontally about a vertical axis. Pressurized liquid in the container flows at high speed through a penstock into, and ultimately through, a turbine to generate electricity.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims benefit of U.S. provisional patent application Ser. No. 60/766,126, filed Dec. 31, 2005, the disclosure of which is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to renewable energy. More particularly, the present invention relates to a device and method of generating appreciable hydroelectric energy. 
       BACKGROUND OF THE INVENTION 
       [0003]    Generation of energy is needed to support the world&#39;s growing population and economy. Energy demands are currently taxing the existing electrical energy supply. To meet the energy demand, there has been great interest in exploiting renewable energy resources, such as hydroelectric power. 
         [0004]    Hydroelectric power is generated when kinetic energy is extracted from flowing water and used to rotate a turbine to produce electric power. Generally, large-scale hydroelectric power generation requires a water source such as a river, dam or reservoir. 
         [0005]    Dams used in conventional hydroelectric power systems have been linked to negative physical, chemical and biological effects on the bodies of water to which these dams are disposed. These negative environmental effects manifest themselves in habitat destruction, obstructions to natural fish movement, poor water quality, over-harvest of natural resources and competition from non-indigenous species. Further, hydroelectric dams may degrade riverine habitat and impede movement of migratory fishes to and from their natal streams. 
         [0006]    One common type of dam is a pumped storage dam. When two reservoirs exist at different elevations in the same general vicinity, a pumped-storage scheme is commonly used to store and produce hydroelectric energy for addressing high peak demands for electricity. At times of low electrical demand, excess electrical capacity is utilized to pump water into the higher reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine, generating hydroelectricity. Because wholesale rates for electricity may be markedly lower during night time than during the day, a pumped-storage hydroelectric system tends to be an economically feasible alternative to traditional methods of generating hydroelectric power. However, due to evaporation losses from the exposed water surface and mechanical efficiency losses during conversion, only between 70 percent and 85 percent of the electrical energy used to pump the water into the elevated reservoir can be regained in the process. 
         [0007]    In any hydroelectric energy generating system, the amount of electric power produced is basically proportional to the flow rate, unit weight of fluid (water), and available hydraulic head through the turbine(s). Thus, in order to maximize the power generated, major hydroelectric energy facilities have typically been constructed where high hydraulic head is available through natural (e.g., waterfalls) or manmade (e.g., dams/reservoirs) means. In smaller-scale applications, the energy from flowing rivers or streams has also been tapped for conversion to electricity. 
         [0008]    In all these cases, the unit weight of the fluid (water) is taken for granted or is assumed not to change significantly during envisioned operational scenarios. This seemingly natural propensity to assume a uniform unit weight of fluid actually tends to overlook the fundamental concept of the unit weight as a function of both the mass density and acceleration due to gravity. Although the fluid mass density is essentially constant, the acceleration due to gravity can change, depending on the location, planet, or environment, such as in a centrifuge. 
         [0009]    The application of centrifuge principles is prevalent in various fields of science and engineering. For example, in chemical and medical facilities, a centrifuge apparatus is generally used to induce separation between substances previously mixed in liquid solution, typically placed in laboratory test tubes. In the field of civil engineering, high-capacity centrifuges have commonly been used to perform model-scale testing of large-scale geotechnical systems in order to simulate the same level of stresses and pressures that would exist in the real-world condition. 
         [0010]    Therefore a need exists for an improved device and method for the production of hydroelectric energy. 
       SUMMARY OF THE INVENTION 
       [0011]    The foregoing needs are met by the present invention, wherein, in one aspect, a compact-sized device for generating appreciable hydropower by taking advantage of high-gravity effects induced with a centrifuge apparatus is provided. 
         [0012]    Borrowing from geotechnical modeling techniques, a miniature-scale replica of a typical real-world hydroelectric system comprising a reservoir, penstock, and turbine(s) can be built, to be mounted and spun in a centrifuge setting. The elevated gravitational field induced in the centrifuge setting will cause the fluid in the miniature-scale model to be heavily pressurized, potentially increasing the power that can be generated in this environment, even though the available hydraulic head appears small. The effluent fluid from the turbine(s) will be directed out of the high-gravity environment toward a central collection bin, where the fluid will be pumped up against normal gravity and redirected via a central feeder toward the reservoir in the spinning miniature model. 
         [0013]    The high-gravity field in the miniature model will also increase the velocity at which the fluid will flow through the penstock toward the turbine(s), but the diameter sizes of the penstock and other conduits in this system can be designed and constructed such that the inflows and outflows can be regulated accordingly. The fluid levels in the “upper” reservoir (in the miniature model) and in the “lower” reservoir (in the central collection bin) will be monitored in conjunction with a feedback-loop mechanism, such that the centrifuge rotational speed and/or pumping rate can be adjusted as necessary. 
         [0014]    This hydropower generating scheme is analogous to a pumped-storage system typically implemented with full-scale reservoirs, except that the proposed scheme seeks to exploit the favorable differences in prevailing gravitational acceleration fields provided by the centrifuge. 
         [0015]    Therefore, in accordance with one embodiment of the present invention, a device having a central shaft is provided. The central shaft has an exterior surface. At least one radial arm having first and second ends are attached to the central shaft in a horizontal position. At least one container is attached to the first end of the radial arm. The container has at least one opening and at least one turbine in communication with a corresponding opening. Additionally, a central feeder is attached to the central shaft. Further, at least one penstock is connected to the central shaft. At least one horizontal conduit is attached to the central feeder. The horizontal conduit has an end that is positioned above a corresponding container. Also attached to the central feeder is a vertical conduit. A lower reservoir with a pump attached to an end of the vertical conduit is associated with the vertical conduit. At least one electrical slip ring is positioned on the exterior surface of the central shaft. The electrical slip ring is in electrical communication with each turbine. Also, an energy storage vessel is in electrical communication with the electrical slip ring. An external power source is attached to the central shaft. 
         [0016]    In accordance with another embodiment of the present invention, a device having a central shaft with a top end and a bottom end and an exterior surface is provided. At least one radial arm is attached to the central shaft in a horizontal position. The radial arm has a first end and a second end. At least one container is attached to the first end of the radial arm. At least one additional container is attached to the second end of the radial arm. The first and second end containers each comprise at least one opening, at least one penstock attached to each opening and at least one turbine attached proximate to each penstock. A central feeder is attached to the bottom end of the central shaft. At least one horizontal conduit having a first end and a second end is attached to the central feeder. The first end of one horizontal conduit is positioned above the first container and the second end positioned above the additional container. Additionally, a vertical conduit is attached to the central feeder. A reservoir with a pump associated therewith is also provided and attached to an end of the vertical conduit. At least one electrical slip ring is positioned on the exterior surface of the central shaft. The electrical slip ring is in electrical communication with one or more of the turbines. An energy storage vessel is in electrical communication with the electrical slip ring. An external power source is attached to the central shaft. 
         [0017]    In an alternate embodiment of the present invention, a device having a central shaft having an exterior surface is provided. A central feeder is attached to the central shaft. At least one conduit having an end is attached to the central feeder. Additionally, at least one penstock is attached to the conduit. At least one turbine is attached to the end of the conduit. At least one electrical slip ring is positioned on the exterior surface of the central shaft. The electrical slip ring is in electrical communication with the turbine. An energy storage vessel is in electrical communication with the electrical slip ring. Further, a liquid source is attached to the central feeder. An external power source is attached to the central shaft. 
         [0018]    In accordance with a further embodiment of the present invention, a method of producing energy is provided. According to the method, at least one container and a liquid are provided. The container comprises at least one opening and at least one turbine in communication with the a corresponding opening. A centrifuge supporting the container is operated. The container is filled with a liquid. The liquid is allowed to flow through the opening into, and ultimately through the turbine(s). Energy is extracted from each turbine. The steps of this, or any method, according to the present invention may be performed in any order. 
         [0019]    There has thus been outlined certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
         [0020]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
         [0021]    As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The invention can be understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Also, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0023]      FIG. 1  is a schematic view of the device according to an embodiment of the present invention; 
           [0024]      FIG. 2  is a graphic representation of a device according to another embodiment of the present invention; 
           [0025]      FIG. 3  is an operational view of the device according to  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. 
         [0027]    With reference to  FIG. 1 , shown is a view of the device according to an embodiment of the present invention. The device shown has an upper reservoir  12  and a lower reservoir  22 . The upper reservoir  12  is formed by filling an upper container  11  with a liquid. The liquid could be any liquid, including water. The upper container  11  has an opening with a release valve  48  proximate thereto. With the release valve  48  open, fluid discharges out from the upper reservoir  12 , through a penstock  13  and turbine/generator  14 , into a lower container  21  holding a lower reservoir  22 . 
         [0028]    The turbine/generator  14  includes conventional components (not shown), such as blades, rotating element(s), windings, and magnet(s), to transform the energy of flowing liquid into rotational energy and eventually into electrical energy. The turbine can be any type of turbine including, for example, a Francis turbine, Kaplan turbine, Propeller turbine, Bulb turbine, Tube turbine, Straflo turbine, Tyson turbine, or water wheel turbine. Alternatively, the turbine can be an impulse turbine such as, a Pelton turbine, Turgo turbine, and Michell-Banki turbine (also known as the crossflow or Ossberger turbine). 
         [0029]    A pump  23 , in the lower reservoir  22  helps bring the liquid back into the upper reservoir  12  through a vertical conduit  25  and horizontal conduit  26 , via a central feeder  24 . This process can be repeated accordingly. 
         [0030]    The pump  23  can be any type of pump. It can be operated electrically, by manual manipulation, or the like. The pump  23  can work at a constant rate or at a variable speed. The conduits  25  and  26  can be any type of channel, pipe, or the like, capable of allowing a liquid to flow from one location to the next. The conduits can be formed from any material including, metals, plastics, rubbers, natural material, synthetic material, or any combination thereof. The central feeder  24  can be any type of connector capable of receiving the vertical conduit  25  and horizontal conduit  26 . For example, the central feeder  24  can be a swiveling pipe joint. In addition, the upper container  11  can be any size or shape capable of forming a reservoir  12 . 
         [0031]    By securely suspending an upper container  11  at the end of a relatively long radial arm  19  that can spin around a vertical axis  18  such that the container  11  swings outward as the radial arm  19  rotates, the upper reservoir  12  can effectively be subjected to an elevated gravity field due to centrifugal inertia. Since the energy input to a pump or output from a turbine is proportional to the ambient gravitational acceleration, the fact that the lower reservoir  22  remains outside the influence of the elevated gravity field leads to a rather favorable energy situation, notwithstanding the additional energy requirement for spinning the upper reservoir. For purposes of this invention, an upper reservoir may include any element attachable to the upper container  11 , either directly or indirectly, with the exception of the radial arm  26 . 
         [0032]    As shown, the device has two identical upper containers  11  attached to radial arm  19 . In alternative embodiments the upper containers  11  can be attached directly to the horizontal conduit  26 . Additionally, more than one radial arm  19  may be provided in alternative embodiments. The radial arm  19  can be formed from any material including plastics, rubbers, polymers, synthetic material, and natural materials. Further, the upper containers  11  can be attached by any connector, such as a chain, string, or the like. The upper container  11  is attached to the radial arm  19  at a freely rotating support and connector  20 . 
         [0033]    In further alternative embodiments, the device can operate with a single, or multiple, containers  11  provided that a counterweight or force allows the device to accelerate to a point that a centrifugal force acts upon the container  11 . If the radial arm  19  extends beyond two sides of the central feeder  18 , suspending equal masses at the ends of the radial arm  19  will balance the arm, thereby improving efficiency. Therefore, more than two packages capable of producing energy may be installed and balanced around the vertical axis  18  as the system capacities and space constraints allow. 
         [0034]    Additionally, the diameter sizes of the penstocks  13  and the conduits  25  and  26  are designed and constructed such that the inflows and outflows can be regulated accordingly. Further, a fluid-level-monitoring system can regulate the amount of liquid available to the upper/bucket container  11 . The fluid-level-monitoring system monitors the high-water and low-water levels in the upper containers  11  using a high water sensor  42  and a low water sensor  43 , respectively, during system operation. Depending on the level of liquid in the upper container, the centrifuge rotational speed about the central axis  18  and/or the pumping rate from the lower reservoir  22  can be adjusted manually or automatically using programmable logic controllers such as a rotational speed controller  33  and a pumping rate controller  36 . The level of the lower reservoir  22  will also need to be monitored through sensor  46 , to determine if additional liquid is required for the hydropower generation system due to evaporation or other losses. 
         [0035]    Electrical communication between the elements of the present invention may be achieved with wires. A number of wires are shown in  FIG. 1 . For example: there is wire  30  extending between the electrical slip ring  27  and the charge control controller/regulator  29 ; a wire  31  extends between the charge controller/regulator  29  and the external energy source  15 ; a wire  34  extends between the external energy source  15  and the power inverter  32 ; a wire  35  extends between the rotational speed controller  33  and the motor  16 ; a wire  37  extends between the pumping rate controller  36  and the pump  23 ; a wire  38  extends between the external energy source  15  and the rotational speed controller  33 ; a wire  39  extends between the electrical energy source  15  and the pumping rate controller  33 ; a wire  41  extends between the power inverter  32  to the electrical load  40 ; a wire  44  extends between the high-water-level sensor in the upper reservoir  42  and the electric slip ring  27 ; a wire  45  extends between the low-water-level sensor  43  and the lower reservoir  22 ; and a wire  47  extends between the external energy source  15  to the water-level sensor in the lower reservoir  46 . As the skilled artisan would realize, the device may be wired in a number of non-limiting manners. 
         [0036]    Turning now to  FIG. 2 , shown is a graphic representation of a device according to another embodiment of the present invention. According to the device of  FIG. 2 , the need for an upper reservoir  12  may be eliminated by extending the length of the vertical conduit  25  preceding the turbine/generator  14 . According to the embodiment shown, the penstock  13  is connected directly to the central feeder  24 . This embodiment also eliminates the need for a feedback-loop mechanism to monitor the upper reservoir  12  fluid levels, while still tapping the power-generating potential of a pressurized fluid flowing continuously at high speeds and discharge rates induced in a centrifuge environment. 
         [0037]    Besides the induced elevated pseudo-gravitational field, a desirable and derivable effect of this centrifuge-based invention is the continuously flowing effluent fluid through the penstock  13  and turbine  14  at discharge rates much higher than when otherwise placed under normal gravity. According to the embodiment of the present invention shown in  FIG. 2 , the need for an “upper” reservoir storage and a fluid-level-monitoring mechanism is eliminated by essentially connecting the penstock  13  directly to the central feeder  24 , while still retaining the ability to convert the kinetic energy of the rapidly flowing pressurized fluid (by centrifugal action) into electrical energy via the turbine  14 . 
         [0038]    As shown, primarily for balancing purposes, suspending a mass at one end of the radial arm  19  requires the same mass or an equivalent force acting opposite to the mass be at the other end. As suggested, more than two packages capable of producing energy may be installed and balanced around the vertical axis  18  as the system capacities and space constraints allow. 
         [0039]    Referring now to  FIG. 3 , shown is an operational view of the device according to  FIG. 2  a motor  16  powered by an external energy source  15 , possibly through a power inverter  32 , drives the central shaft  18 , rotating the radial arm  19  of a centrifuge system about the vertical axis of the central shaft  18 . A structural mount for motor  17  is attached to the motor for support. The external energy source can be rechargeable. Accordingly, the external energy source  15  is also referred to as the external energy storage or as an energy storage vessel. The external energy source/storage  15  can be any source capable of providing and receiving energy, such as a rechargeable battery. 
         [0040]    As the radial arms  19  rotate about the vertical axis of the central shaft  18 , the securely suspended upper containers  11  swing radially outward along with any attached components, such as the penstocks  13  and turbines  14 . In such configuration, fluid discharging through the penstocks  13  and turbines  14  will tend to generate greater energy than under normal gravity, depending on the centrifuge speed of rotation about the central axis  18 . 
         [0041]    The effluent fluid from the turbines  14  is directed out of the high-gravity environment of the upper buckets  11  toward the centrally located lower reservoir  22 . The pump  23 , which is powered either directly by the external energy source  15  or through the power inverter  32 , causes the liquid to flow upward against normal gravity from the lower reservoir  22  through the central conduit  25 . With the use of the central feeder  24 , the liquid can be redirected back through the penstocks  13  and to the turbines  14 , where the flow cycle ends and begins anew. 
         [0042]    Electricity generated from the turbines  14  can be used to recharge the electrical energy storage (e.g., battery, or the like) unit  15  by directing the current to flow via appropriate wirings  28 ,  30 , and  31  through an electrical slip ring connection  27  that is concentrically positioned with the central shaft  18 . A charge regulator  29  is installed to monitor the charge status of the electrical energy storage unit  15 , and to ensure that the electrical energy storage unit  15  is not overcharged. The electrical energy storage unit  15  can then be tapped to power the electrical components in the system and possibly other external electrical loads  40 . 
         [0043]    The diameter sizes of the penstocks  13  and the conduits  25  and  26  are designed and constructed such that the inflows and outflows can be regulated accordingly. The level of the lower reservoir  22  may need to be monitored to determine if additional liquid is required for the hydropower generation system due to evaporation or other losses. 
         [0044]    The present invention is also drawn to various methods for using the devices for producing hydroelectric energy disclosed herein. 
         [0045]    In accordance with a further embodiment of the present invention, a method of producing energy is provided. According to the method at least one container and a liquid are provided. At least one container comprises at least one opening and at least one turbine in communication with at least one opening. A centrifuge supporting at least one container is operated. Each container is filled with a liquid. The liquid is allowed to flow through each opening into, and ultimately through each turbine. Energy is extracted from each turbine. The steps of this, or any method, according to the present invention may be performed in any order. 
         [0046]    In another step, the electricity produced by the device can be transmitted to an energy storage vessel. Further, the electricity from the energy storage vessel may be transmitted to an external load. Additionally a constant amount of liquid may be maintained in each container. 
         [0047]    According to an additional embodiment of the present invention, at least one additional container is provided. Similarly to the first container, each additional container comprises at least one opening and at least one turbine attached to each opening. Each additional container is filled with a liquid. The liquid is allowed to flow each opening into, and through each corresponding turbine while operating the centrifuge. Energy is extracted from each turbine. Additionally, a constant amount of liquid is maintained in each container. 
         [0048]    The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.