Abstract
The present invention provides novel designs and improved methods for the construction and operation of a gravity powered energy storage facility. This facility might also be called a gravity battery or a gravitational potential energy storage device. The device converts electricity into gravitational potential energy, and vice versa, by raising and lowering massive modules between a higher elevation and a lower elevation. These modules could maximize their mass with weight container units consisting of any heavy medium, such as water, stone, metal, concrete, compacted earth, etc. The present invention includes such designs and design optimizations which can achieve such scale. To accomplish this, the system's height is optimized by utilizing an underground vertical shaft which can provide a large height differential. And the system's weight is optimized by implementing a modular design which can evenly distribute a very large load. This modular design uses multiple tethers, gears, or other supporting elements to evenly distribute the load for modular sections of weight. Further design elements optimize this system for peak performance.
Claims
1: A gravity-powered energy storage system, comprising: a. a substantially vertical shaft spanning a large height, b. a plurality of heavy modules, and c. a power transmission system.
2: The system of claim 1, further comprising a pathway through the substantially vertical shaft and one or more substantially horizontal pathways, said one or more substantially horizontal pathways connecting to said pathway through the substantially vertical shaft in such a way as to allow transportation of modules between each pathway.
3: The system of claim 1, wherein said power transmission system transmits power between said modules.
4: The system of claim 3, further comprising at least one power conversion system, wherein said power transmission system further transmits power between said modules and said power conversion system.
5: The system of claim 4, further comprising at least one external power grid, wherein said power conversion system further transmits power between said modules and said external power grid.
6: The system of claim 1, wherein said shaft is arranged underground into bedrock.
7: The system of claim 2, wherein the system further comprises one or more transition portions between said substantially vertical and substantially horizontal portions and wherein said transition portions facilitate the continuous movement of modules along a guided path through all pathways.
8: The system of claim 7, wherein said heavy modules are guided along said guided path through a supporting mechanism which enables the modules to travel back and forth along said guided path.
9: The system of claim 8, wherein said supporting mechanism is a load-bearing track which supports loads both perpendicular to the track and parallel to the track, the latter which is achieved through an interaction selected from the group consisting of (1) a rolling friction interaction, (2) a geared interaction, (3) a mechanical gripping interaction, or (4) an electromagnetic interaction.
10: The system of claim 8, wherein said modules each comprise at least one motor to locomote said module along the path.
11: The system of claim 8, wherein said modules each comprise at least one generator to generate power to transmit to said external power grid.
12: The system of claim 8, wherein said modules further comprise a connecting assembly which connects each of said modules to said track and enables the module to locomote along said track.
13: The system of claim 12, wherein said connecting assembly comprises one or more motor/generator units and gear assemblies.
14: The system of claim 13, wherein said connecting assembly further comprises at least one gear which transmits a force through said connecting assembly to said motor/generators, thereby providing a force to counter the gravitational force to slow the module's natural rate of descent.
15: The system of claim 14, wherein said modules each comprise at least one gear-reduction mechanism for altering the properties of torque and speed for said at least one gear.
16: A modular unit for a modular gravity-powered energy storage system which comprises a plurality of said modular units arranged in a series for converting gravitational potential energy to electrical energy.
17: The modular unit of claim 16 comprising at least one secondary energy storage system selected from the group consisting of (1) a rotational energy storage system comprising one or more flywheels, (2) a chemical battery energy storage system, and (4) a thermal energy storage system.
18: The modular unit of claim 17, further comprising an integrating device for integrating the gravity energy storage system and the one or more secondary energy storage systems.
19: The modular unit of claim 16, wherein said unit comprises a software system to control the unit's internal functionality and/or communicate with the overall system.
20: The system of claim 1, wherein said modules are adapted to absorb, store, and release thermal energy.
21: The system of claim 1, further comprising a lifting device, wherein said heavy modules are adapted to be lifted and lowered within said shaft, wherein said weights are lowered from an upper storage location to a lower location, thereby generating energy.
22: The system of claim 21, further comprising a plurality of tethers arranged to detachably fix to said lifting device and said heavy modules.
23: The system of claim 1, further comprising load-bearing elements secured to the walls of the shaft, wherein said load bearing elements engage with said modules to facilitate lifting and lowering of said modules.
24: The system of claim 1, further comprising a load-bearing conveyor system which is secured to the walls of the shaft in such a way as to not limit the conveyance motion, and wherein said conveyor system interacts with said modules to facilitate lifting and lowering of said modules.
25: The system of claim 24, further comprising at least one motor/generator assembly which interacts with said conveyor system to power its motion or to generate power from its motion, wherein said at least one motor/generator assembly is arranged along a height of the vertical shaft and secured to a wall of the shaft.
26: The system of claim 25, wherein said shaft further comprises at least one recess cut into a wall of said shaft, wherein said at least one motor/generator assembly is installed into said recess.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] FIG. 1 is an exploded view of the module driver assembly, revealing module driver assembly wheels with geared surfaces and integrated motor/generator units and integrated gear-reduction mechanisms.
[0053] FIG. 2 is an axonometric view of a module along a vertical section of track. The module has two module driver assembly units and multiple weight container units.
[0054] FIG. 3 is an axonometric view of a module driver assembly connected to a vertical section of track. The module driver assembly unit is shown isolated, without any weight container units.
[0055] FIG. 4 is an axonometric, partial section view of the inside of a module driver assembly unit. The casing is removed to reveal inner components. The driver assembly unit is shown isolated, without any weight container units. A partial section cuts away the assembly wheels with geared surfaces to reveal integrated motor/generator units and integrated gear-reduction mechanisms. In this illustration, the gear-reduction mechanism is a cycloidal gear assembly.
[0056] FIG. 5 is an axonometric view of an installation with virtual trains of modules along the installation's rail-guided pathway. The drawing shows a vertical pathway section mined out of bedrock, and two horizontal pathway sections—one above ground, and one underground also mined out of bedrock. Notes: the drawing is not to scale, and the various locations of the modules are to show various visual examples at once, and they do not represent a typical installation layout of modules.
[0057] FIG. 6 is an axonometric view of an energy storage system of modules connected to an external power grid, and integrated with a power transmission system comprising components such as a Power Conversion System, a DC electric rail, and various other components. One module is shown in partial section view to reveal internal components such as the module driver assembly wheels with geared surfaces.
[0058] FIG. 7 is an axonometric, partial section view of a module with secondary storage elements. The module is on a track next to adjacent modules in a virtual train. The partial section view reveals the internal components such as the module driver assembly wheels with geared surfaces, and two secondary storage units of different types—one is a chemical battery energy storage system, and another is a flywheel rotational energy storage system.
[0059] FIG. 8 is a top view of a spiral track based system design. The top view of a module is shown with various module driver assembly units around its perimeter. Some module driver assembly units are shown above the visible length of track, and some are obscured because they have turned under the visible length of track.
[0060] FIG. 9 is a perspective view of a spiral track based system design. A module is shown with various module drivers.
[0061] FIG. 10 is an elevation view of a spiral track based system design. A module is shown with various module drivers.
[0062] FIG. 11 is an axonometric, partial section view of a cable-based system design. The illustration shows multiple cables passing through various cable guiding channels, and it shows a load-bearing bracket with latching mechanisms with a lever and pin device.
[0063] FIG. 12 is an elevation view of a cable-based system design. The illustration shows a stack of load-bearing brackets—each with latching mechanisms with a lever and pin device. Only the bottom-most load-bearing bracket has an extended lever. The other load-bearing brackets have lifted levers.
[0064] FIG. 13 is an axonometric, partial section view of a cable-based system design with multiple cables designed to support multiple modular weights with a system of load-bearing brackets.
[0065] FIG. 14 is an axonometric view of crane-based system design where the crane assembly is located at ground level over a substantially vertical pathway in the form of a shaft. The crane is shown placing or removing modules from radial stacks around the shaft to move them to or from the vertical shaft.
[0066] FIG. 15 is an axonometric view of a conveyor-based system design embedded in a vertical shaft. The illustration shows module driver assembly units installed in cavities excavated into bedrock. These module driver assembly units drive a conveyor belt mechanism which interacts with modular weights inside the shaft to lift them or to slow the module's natural rate of descent from the gravitational force which also provides a regenerative braking force to the motor/generator unit thereby producing power.
REFERENCE NUMERALS IN THE DRAWINGS
[0067] 1. Ground surface [0068] 2. Bedrock [0069] 3. Horizontal pathway, above ground, or excavated just below grade [0070] 4. Horizontal pathway, mined out of bedrock [0071] 5. Vertical pathway, mined out of bedrock [0072] 6. Pathway transition portion between horizontal and vertical [0073] 7. Load bearing track
[0074] a. Load bearing track—outer track pair
[0075] b. Load bearing track—center track
[0076] c. Load bearing track, in spiral ramp formation
[0077] d. Load bearing track—geared threads [0078] 8. Module with driver assemblies and weight container units [0079] 9. Module weight container unit [0080] 10. Module power connection to electric rail (i.e an electric rail “shoe” connection) [0081] 11. Module controller [0082] 12. Module driver assembly
[0083] a. Module driver assembly axle
[0084] b. Module driver assembly wheels with geared surface
[0085] c. Module driver assembly wheels with integrated motor/generator units
[0086] d. Module driver assembly wheels with integrated gear-reduction mechanism
[0087] e. Module driver assembly motor/generator stator
[0088] f. Module driver assembly motor/generator rotor
[0089] g. Module driver assembly casing [0090] 13. Module secondary storage—chemical battery energy storage system [0091] 14. Module secondary storage—flywheel rotational energy storage system [0092] 15. Module power connection to module controller [0093] 16. Module power connection to secondary storage system [0094] 17. DC electric rail (i.e. “third rail”)
[0095] a. DC electric rail cover
[0096] b. DC electric rail connection point [0097] 18. DC switch [0098] 19. AC breaker [0099] 20. Power Conversion System (PCS) including typical power station components such as Inverters, Transformers, Protection Switches and Breakers, and Energy Management systems (EMS) [0100] 21. DC power connections [0101] 22. AC power connections [0102] 23. External power grid [0103] 24. Module unit with motor/generators—one of many, in train formations along pathway [0104] 25. Tunnel entrance where pathway may transition between ground surface and excavated area. [0105] 26. Module-supporting crane assembly with motor/generators which can move modules vertically and also with crane arms which can move modules laterally in order to stack and unstack them. [0106] 27. Module-supporting cable or tether [0107] 28. Module-supporting conveyor belt [0108] 29. Module-supporting cable guiding channel [0109] 30. Module-supporting load-bearing bracket [0110] 31. Module-supporting load-bearing bracket latching mechanism with lever and pin
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION
[0111] Illustrated in FIGS. 5-7 is a modular gravity-powered energy storage system which comprises a plurality of heavy modules which together have a desirable aggregated effect on the energy storage system. As illustrated in FIG. 7, each module may contain or integrate one or more secondary energy storage technologies such as but not limited to a rotational energy storage system (e.g. flywheels), a chemical battery energy storage system (flow batteries, Li-ion batteries, or other), or a thermal energy storage system. The weight of this secondary energy storage device contributes to the gravitational potential energy used by the gravity storage module and the secondary energy storage technology contributes additional energy storage potential to the overall system. A mechanical and/or software system connects/integrates the gravity storage system and the secondary storage system.
[0112] FIG. 3 shows a gravity-powered energy storage system, comprising a track which spans a large height and a plurality of heavy modules which can locomote along that track wherein said track is arranged underground into a bedrock shaft. The shaft can be any advantageous depth, preferably greater than 0.5 miles deep. (Greater height gives longer energy storage duration). FIG. 3 also shows various sections of track—some arranged substantially vertically and some arranged substantially horizontally—and transition portions between said substantially vertical and substantially horizontal portions.
[0113] FIG. 6 further shows the system comprising at least one power conversion system and a number of power components to transmit power between said modules and said power conversion system. FIG. 6 also shows at least one external power grid wherein said power conversion system further transmits power between said modules and said external power grid.
[0114] FIGS. 1-4 illustrate a module design comprising one or more module driver assemblies which include motor/generators to drive the module along the track as well as to generate power through a regenerative braking effect as the motor/generators slow the module's natural rate of descent from the gravitational force. These figures further show the module driver assemblies comprising gears which connect each module to said track and enable the module to locomote itself along the track in a secure and controlled manner. FIG. 2 further shows various module weight container units added to increase the density of the module.
[0115] FIGS. 13-15 show various embodiments of the present energy storage system in which the system comprises motor/generators which are external to the heavy modules. In these various embodiments, said external motor/generators may leverage some connecting device such as cables or conveyor belts to exchange a force with said heavy modules which in turn locomotes said modules along said pathway.
[0116] FIG. 4 illustrates a module driver assembly for a module of the present system comprising three wheels with geared surfaces—two outer wheels and one center wheel. Each outer wheel includes an integrated motor/generator to locomote said module along the track and to generate power from the deceleration of said module along said track. The center wheel includes an integrated gear-reduction mechanism. The outer wheels are connected to the center wheel through a module driver assembly axle. The outer wheels' motor/generators may exert forces on the center wheel's gear-reduction mechanism which causes the center wheel to rotate relative to the outer wheels. The gear-reduction mechanism may cause this rotation to have decreased speed and increased torque. FIG. 4 further shows each wheel with a geared surface which connects said module to the track which has a matching geared surface. These geared surfaces together can be understood as rack and pinion gears. The tracks which match the outer wheels are on the opposite side of the pathway as the track which matches the center wheel. This allows the wheel's opposite rotation to exert a force in the same direction along the pathway which enables the module driver assembly to drive the module.
[0117] FIGS. 8-10 illustrate an embodiment of the invention wherein at least some portion of said substantially vertical pathway is comprised of one or more tracks which are in the shape of a spiral. This spiral may be fixed to a shaft wall so that it forms a load-bearing ramp at the edges of the shaft. If it is advantageous, multiple instances of said spiral track may be utilized, where each instance can be offset in rotation to form various helical shapes such as a double helix, triple helix, etc. as illustrated. FIGS. 8-10 further show module driver assemblies with geared wheels which are located on the outside of the module and positioned in such a manner that they can interact with the ramp surface of said spiral tracks for the purpose of driving the module. As illustrated, these module driver assemblies may be offset to the correct height and rotational angle to properly engage with the spiral track while supporting the weight of the heavy module and keeping the module level.
[0118] FIGS. 11-13 illustrate another embodiment wherein the energy storage system comprises a modular design which allows for a scalable number of many cables or tethers to support sections of weight so as to avoid supporting all of the weight with one tethered connection. Motor/generator units located at ground level extend said cables through various cable guiding channels which guide each cable to attach to a module load-bearing bracket. FIG. 11 further shows that said load-bearing bracket may contain one or more load-bearing bracket latching mechanisms. FIG. 12. further shows that said load-bearing brackets may be stacked. As illustrated in FIGS. 11-12, the latching mechanism can be designed in such a way to allow for the bottom-most module to always fall through the top load-bearing brackets (whose latching mechanisms are lifted) until it hits the bottom-most load-bearing bracket whose latching mechanism is extended. This latching mechanism works with a lever and a pin whereby the lever falls into the extended position unless a load-bearing bracket below it presses up onto its pin which lifts the lever. In this way, as the load-bearing brackets above are pulled up flush against one another, their latching mechanisms will be lifted, providing an open channel for weights to fall through until they hit the bottom load-bearing bracket. This design allows for each module to be assigned its own load-bearing bracket, which in turn designates to each module its own pair of load-bearing cables, thus distributing the modules' combined gravitational load amongst the system of many cables or tethers.
[0119] FIG. 14 illustrates another embodiment wherein a module supporting crane assembly is located at ground level over a substantially vertical pathway in the form of a shaft. The crane assembly includes motor/generators which can lift and drop the modules vertically along the axis of the gravitational force. The crane assembly also includes arm mechanisms which are typical of a crane which can move the modules in lateral directions thus enabling the system to stack and unstack said modules in some convenient formation such as in stacked rings around said shaft, and also enabling the system to raise and lower said modules into and out of the vertical shaft.
[0120] FIG. 15 illustrates another embodiment wherein a module supporting conveyor belt is positioned vertically along a substantially vertical pathway in the form of a shaft. The conveyor belt is driven by motor/generators which are located along the vertical portion of the pathway and may be installed into cavities excavated into bedrock. The module supporting conveyor belt enables the system to raise and lower said modules inside of the shaft.
[0121] While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.
