CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63/202,676, titled “Underground Well Energy Storage,” filed by Federico Marques, et ak, on June 21, 2021. [0002] This application incorporates the entire contents of the foregoing application(s) herein by reference.

TECHNICAL FIELD

[0003] Various embodiments relate generally to renewable energy storage systems.

BACKGROUND

[0004] A gravity battery is a type of energy storage device that stores gravitational energy. For example, a gravity battery may operate by using excess energy from the grid to raise a mass to generate gravitational potential energy. To convert the gravitational potential energy back to electrical energy, for example, the mass may be dropped to a lower gravitational position to work an electric generator to generate electrical energy. In various examples, energy generated from a gravity battery is a form of sustainable energy. For example, generating gravitational energy may produce very little or no pollutant.

[0005] One form of a gravity battery is one that lowers a mass, such as a block of concrete, to generate electricity. A common gravity battery is used in pumped-storage hydroelectricity, where water is pumped to higher elevations to store energy and released through water turbines to generate electricity.

[0006] Many solar and wind power generators are in remote areas where many abandoned wells (e.g., oil wells, gas wells, water wells) are located nearby (e.g., < 1 mile). In many examples, these wells may be plugged, for example, at bottom before repurposing. In some examples, these wells may be more than 5000 ft deep.

SUMMARY

[0007] Apparatus and associated methods relate to a gravitational energy storage system. In an illustrative example, a portable container (e.g., a 20 foot shipping container) may be disposed with a series of motors-generators to electively lift and lower a weight(s) in a vertical shaft (e.g., an abandoned wellbore) for storing gravitational energy. The portable container, for example, may include a foldable crane configured to deploy and/or guide a series of weight segments making up the weight. The weight may be, for example, be coupled to a rotating winching system disposed in the portable container via a cable. The winching system, for example, may be coupled to a transmission. The transmission may be selectively controlled by a controller. For example, the controller may selectively operate the transmission and the motor generator to move the multiple weight segments within the vertical shaft. Various embodiments may advantageously enable rapid field deployment of gravitational batteries.

[0008] Various embodiments may achieve one or more advantages. For example, abandoned wells may pose danger to the public and/or be a waste of land if left unmaintained. Various implementations may advantageously provide an environmentally friendly, sustainable, and economical solution to repurpose these wells. For example, portable, pre-containerized gravitational batteries may advantageously be rapidly deployed to improve energy efficiency of renewable energy sources.

[0009] As an illustrative example, for example, 100 or more containerized power storage systems (CPSSs), such as disclosed herein, may be deployed in a single day. The CPSSs may be efficiently and cost-effectively built offsite (e.g., at a controlled manufacturing center where labor and materials may be readily available) and then deployed to sites (e.g., remote sites) needing energy storage and having available shafts (e.g., abandoned oil wells), even if those sites have limited availability of labor and/or materials. In some implementations, by way of example and not limitation, a small team (e.g., one, two, three persons) may deploy a CPSS in less than one day. [0010] Implementation of renewable energy may, for example, be depressed due to fluctuations and/or unreliability in energy generation. For example, wind energy may only be available when wind is blowing above a certain speed. Solar energy may, for example, only be produced during sunny periods. Various CPSS implementations may, for example, advantageously provide a much- needed solution to balancing fluctuations in renewable energy production by providing rapidly deployed energy storage cost-effectively and at the location of energy production with minimal overhead. For example, CPSS may be rapidly installed at an energy generation site to selectively store and release ‘grid-ready’ power with minimal to no on-site facility building needed.

[0011] Some implementations may, for example, include a deadline coupled to the weight to advantageously prevent a cable failure to damage the vertical shaft. For example, one or more of the weight segments may include a self-locking twist-lock collar to advantageously reduce falling speed when a downwards speed of the weight segments exceeds a predetermined threshold [0012] The details of various embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 A depicts an exemplary containerized power storage system (CPSS) employed in an illustrative use-case scenario.

[0014] FIG. IB depicts a front cross section view of an exemplary CPSS during a deployment process.

[0015] FIG. 1C depicts a schematic view of an exemplary CPSS, showing components in action for deploying weights into a vertical shaft.

[0016] FIG. 2 is a schematic diagram depicting an exemplary CPSS in a stowed mode.

[0017] FIG. 3 is a schematic diagram depicting an exemplary CPSS in a deployed mode.

[0018] FIG. 4 is a block diagram depicting a control system of an exemplary CPSS 100.

[0019] FIG. 5 is a flowchart illustrating an exemplary deployment method.

[0020] FIG. 6 is a flowchart illustrating an exemplary operation method.

[0021] FIG. 7 depicts an exemplary weight rod with a fishing grip.

[0022] FIG. 8 depicts an exemplary weight rod with a rod slip.

[0023] FIG. 9 depicts an exemplary weight rod with a deadline.

[0024] Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0025] To aid understanding, this document is organized as follows. First, to help introduce discussion of various embodiments, a containerized power storage system (CPSS) is introduced with reference to FIGS. 1A-3. Second, that introduction leads into a description with reference to FIG. 4 of some exemplary embodiments of a control system of the CPSS. Third, with reference to FIGS. 5-6, exemplary methods are described in application to deploy and operate the CPSS. Fourth, with reference to FIGS. 7-9, the discussion turns to exemplary embodiments that illustrate a failsafe system of the CPSS. Finally, the document discusses further embodiments, exemplary applications and aspects relating to a portable gravitational energy storage system.

[0026] FIG. 1 A depicts an exemplary containerized power storage system (CPSS 100) employed in an illustrative use-case scenario. As shown, in a transportation mode, the CPSS 100 may, for example, be transported by a 20-foot multi-modal (e.g., rail, sea, ground) shipping container 101 on a roll-off bed trailer truck 105. Various embodiments may, by way of example and not limitation, include the CPSS within various standard size shipping containers (e.g., 8ft, 10ft, 20ft, 40ft, 45 ft). In some implementations, two CPSS 100 may be transported to a field site 115 on a back of the roll-off bed trailer truck 105. Such implementations may, for example, advantageously keep delivery costs low. The CPSS 100 also includes a crane 110 (e.g., a jib crane) mounted on the container. For example, the crane 110 may be folded (e.g., folded down) during transportation. [0027] After the roll-off bed trailer truck 105 arrived at the field site 115 (e.g., an abandoned oil well), as shown in this example, the shipping container 101 may, for example, be deployed on top of a standpipe (e.g., 2 ft tall) where a wellbore 140 is located. For example, the wellbore 140 may be 1.5inches to 3inches wide. In some examples, the wellbore may be 8-12 inches wide. In this example, after deployment, the CPSS 100 may supply energy to a power grid 120.

[0028] As shown in FIG. 1 A, the CPSS 100 includes a series of inline motors 125a, 125b, 125c. In some implementations, the inline motors 125a, 125b, 125c may be 200-400hp motors, for example. The inline motors 125a, 125b, 125c together, for example, may produce a force to lift a 20,000 pounds weight vertically 5000-50000ft 2-3 times a day. In some implementations, the inline motors 125a, 125b, 125c may, for example, advantageously be more cost effective than a single motor having a same output power. In various embodiments, for example, 3-4 motors, each 200 horsepower (hp), may be more cost effective than one 600 or 800 hp motor. In some examples, the size of three 200 hp inline motors may advantageously fit (e.g., absolutely, more easily) into the container 101, making the CPSS 100 more mobile. In some implementations, by way of example and not limitation, the inline motors 125a, 125b, and/or 125c may be configured as motor- generators or generators. Although 3 motors 125a, 125b, and 125c are shown, more or less motors may be provided in various implementations (e.g., according to a weight to be translated, according to electricity available and/or to be generated, according to size constraints).

[0029] The inline motors 125a, 125b, 125c are connected to a winch system 130. For example, the winch system 130 may include a ½ inch steel wire line. In some implementations, the winch system 130 may include a polymer line. The winch system 130 is, in this example, connected to a motor- generator 135. In some implementations, the motor-generator 135 may be operated by a rotational force generated from the winch system 130 to generate electricity. For example, the generated energy may be supplied to the power grid 120 though a power interface as discussed with reference to later figures.

[0030] As shown in FIG. 1 A, the winch system 130 is coupled to a weight rod 145. For example, the weight rod 145 may be a continuous steel rod made by coupling multiple segments of steel rods together at the field site 115. In some implementations, the segments of the weight rod 145 may be recycled and/or surplus steel rods readily available. For example, using recycled steel rods may advantageously be environmentally friendly. For example, the recycled steel rods may advantageously be compliant to an industry standard (e.g., oilfield drilling standards) so that the rods may be easily and effectively deployed. For example, the weight rod 145 may weigh 2,000 - 25,000 lbs. During deployment, in some implementations, the crane 110 may include guidewires 116 to guide the multiple segments of steel rods into and/or within the wellbore 150. Various embodiments of coupling multiple segments of the weight rod 145 and deploying the weight rod 145 at the field site 115 are discussed in later figures, particularly with reference to FIG. 1C. [0031] By displacing the weight rod 145 up and down a vertical shaft (e.g., a wellbore 150), the CPSS 100 may store and release energy, respectively. For example, the wellbore 150 may be 5000- 50000 ft deep. In various examples, the weight rod 145 may be a mass with a predetermined weight that may fit within the vertical shaft. For example, the weight rod 145 may also be a concrete rod and/or a concrete block. The weight rod 145 may, for example, be more than one material, such as a pipe (e.g., steel) filled with concrete, lead, surplus material (e.g., waste), and/or other weight. In some examples, the weight rod 145 may be a series of buckets filled with liquid with known density.

[0032] The CPSS 100 further includes a controller 155. For example, the controller 155 may control operations of the inline motors 125a, 125b, 125c and the motor-generator 135. In some implementations, the controller 155 may also control a transmission system that may control speed and/or a rotational direction of the inline motors 125a, 125b, 125c and/or the motor-generator 135. In some implementations, the controller 155 may include a communication module to receive instruction from a cloud control system. For example, the CPSS 100 may be one of many power nodes at the field site 115. The cloud control system may synchronize and coordinate operations of the power nodes so that an output energy is grid ready. For example, the cloud control system may control the power node(s) to generate an electricity with a matching voltage, frequency, and phase with the power grid 120.

[0033] In various implementations, the CPSS 100 may include a series of motor-generators (e.g., the inline motor-generators 125a, 125b, 125c, and 135) housed in a portable container (e.g., the shipping container 101) and configured to selectively lift and lower a weight (e.g., the weight rod 145) within a vertical shaft, and having a folding crane (e.g., the crane 110) coupled to the portable container and configured to deploy and guide a series of weight segments making up the weight. [0034] FIG. IB depicts a front cross section view of an exemplary CPSS 100 during a deployment process. FIG. 1C depicts a schematic view of an exemplary CPSS, showing components in action for deploying weights into a vertical shaft. In the illustrative deployment process shown in FIGS. 1B-1C, the crane 110 is folded up to transfer a segment of weight into the container 101 via an upper aperture 160. As shown in FIG. IB, some segments of the weight rod 145 may be transferred into the wellbore 150 via a lower aperture 165 of the container 101.

[0035] As shown in FIG. 1C, the crane 110 includes a cinch gear 170 for adjusting a fold up angle of the crane 110. After lowering a weight segment into the container 101, in some implementations, the weight segment is coupled to the rest of the weight inserted in the wellbore 150. In this example, the weight segment includes a screw collar 175. Held by the crane 110, the weight segment may be fastened to the rest of the weight using the screw collar 175. For example, the screw collar 175 may include a twist locking mechanism to couple with another weight segment.

[0036] Referring to FIG. IB, the container 101 includes a reinforced roof 180. For example, the crane 110 may, in some examples, lift a weight segment of more than 500-10001bs. In some implementations, the reinforced roof 180 may advantageously improve a strength of the container 101. In some implementations, the crane 110 may be supported by a ground surface by frame members transferring a weight of the crane 110 and active load to side walls of the container 101 and/or the ground surface. The container 101 may, for example, be provided with a reinforcement beam around at least a portion of the bottom periphery of the container 101. The reinforcement beam may, for example, advantageously provide structural integrity to the container 101.

[0037] The CPSS 100 includes, as shown, a data/sensor module 185. For example, the data/sensor module 185 may be operably coupled to the controller 155. In some implementations, the controller 155 may receive and transmit signals to a central server (e.g., a cloud system). For example, the controller 155 may receive instructions from the central server to receive and save energy from a renewable source. For example, the controller 155 may receive instructions from the central server to release energy to the power grid 120. In some implementations, the controller 155 may report a position or height of the weight rod 145 to the central server so that the central server may determine energy stored at each CPSS.

[0038] In this example, the CPSS 100 further includes a cooling module 186. For example, the cooling module 186 may be an air-conditioner. For example, the controller 155 may operate the cooling module 186 based on a temperature measurement at the data/sensor module 185.

[0039] FIG. 2 is a schematic diagram depicting an exemplary CPSS 100 in a stowed mode. As shown, components for deploying of the CPSS 100 may be included within a shipping container 200 so that the CPSS 100 may advantageously be readily and quickly deployed at the field site 115. As shown in this example, the crane 110 is folded down during the stowed mode to, for example, avoid damaging the crane 110 during transportation. In this example, a stack 205 of segments of the weight rod 145 are also stored in the container 200 for easy transportation. In some implementations, each segment of the weight rod 145 may include the screw collar 175 for easy fastening into another segment of the weight rod 145.

[0040] FIG. 3 is a schematic diagram depicting an exemplary CPSS 100 in a deployed mode. As shown in this example, the inline motors 125a, 125b, 125c and the motor-generator 135 are fixedly mounted in the shipping container 200. For example, stators of the inline motors 125a, 125b, 125c and the motor-generator 135 may be mounted on a floor of the shipping container 200. For example, rotors of the inline motors 125a, 125b, 125c and the motor-generator 135 may be connected to a rotating drum of the winch system 130. In some implementations, the winch system 130 may receive power from the inline motors 125a, 125b, 125c and the motor-generator 135 to lift the weight rod 145 to store and release energy. For example, in the deployed mode, the CPSS 100 may receive energy from a nearby renewable generator 300 (e.g., a wind farm as shown in FIG. 3). In some implementations, excess energy generated by the renewable generator 300 may be stored in the CPSS 100 by using the excess energy to lift up the weight rod 145 from, for example, hi to hO. At a later time, when there is an excess demand for energy from the renewable generator 300, the CPSS 100 may release the stored energy into the power grid 120, for example, by dropping the weight rod 145 from hO to hi.

[0041] As an illustrative example, the weight rod 145 may be displaced or dropped from a position hO to another position hi . For example, an energy output by the motor-generator 135 may be given by Mass (kg) x gravity (m/s2) x Height (m) x n(efficiency). For example, if h = hO - hi = 10,000 ft, and the weight rod 145 weighs 9071.8kg, at 75% efficiency, the energy output from the CPSS 100 may be 56.5 kWh output. In various examples, the field site 115 may include 10, 50, or 100 abandoned wells. By deploying fifty CPSS 100 at the field site 115, the total output may be scaled up to 2.5MWh or above.

[0042] In some examples, when there is excess energy generated from the renewable generator 300, the excess energy may power the inline motors 125a, 125b, 125c to lift the weight rod 145 to position hO. When there is an excess demand from the power grid 120, the CPSS 100 may release the weight rod 145 at a selective speed to generate electricity to the power grid 120. In various implementations, the CPSS 100 may advantageously be used for energy storage and reduce toxic disposals. By way of example and not limitation, the CPSS 100, due to its mechanical nature, may be maintained effectively and sustainably with an average 40 year or greater typical life with basic maintenance. For example, there may be no need for replacement of large batteries that contain toxic chemicals. Accordingly, various embodiments may advantageously reduce waste, reduce generation of toxic waste (e.g., battery fumes, battery waste), and/or reduce reliance on toxic materials.

[0043] FIG. 4 is a block diagram depicting a control system 400 of an exemplary CPSS 100. For example, the control system 400 may operate various components of the CPSS 100 to receive excess energy from a generation facility, and to release the stored energy to the power grid 120. The control system 400 includes the controller 155 that operates various components in the CPSS 100. For example, the controller 155 may include a user interface to operate the crane 110. For example, a user may control the crane 110 to fold up and down. In some examples, the user may use the crane to guide an installation of the weight rod 145 via the user interface of the controller. [0044] In this example, the CPSS 100 includes a cloud system 405 operably coupled to a communication module 410. In some implementations, the cloud system 405 may be connected to an electric grid interface to receive information, for example including current power demand and/or power demand forecast, from the power grid 120. For example, the cloud system 405 may communicate with the CPSS 100 via a wireless network. In some implementations, the cloud system 405 may coordinate independently storing and releasing of multiple CPSS 100 based on demands in the power grid 120.

[0045] The controller 155, for example, may receive instructions from the cloud system 405 and operate a motor system 415 and a gearbox 416 (e.g., configured as a transmission) based on the received instructions. The motor system 415 includes the inline motors 125 and the motor- generator 135. For example, the controller 155 may control an output power of the motors 125, 135. The gearbox 416, for example, may be a mechanical gearbox (e.g., a planetary gearbox). In some examples, the gearbox 416 may be an electrical gearbox that includes a variable resistance. In some implementations, the gearbox 416 may include multiple transmission ratios selectable by the controller 155. For example, the controller may control a speed of the weight rod 145 dropping down/lifting up the wellbore 150 using a selected transmission ratio specifying an input speed to output speed ratio.

[0046] The gearbox 416 is coupled to the winch system 130. For example, the winch system 130 may wind a steel cable coupled to the weight rod 145 in the wellbore 150. In this example, the CPSS 100 includes a counteract system 425. For example, the counteract system 425 may act as a failsafe in case there is a cable failure in the wellbore 150. In some implementations, the counteract system 425 may include a deadline (e.g., the deadline 190) that may engage the steel cable and the weight rod 145 when the steel cable and the weight rod is dropping at a speed higher than a predetermined threshold. In various examples, the counteract system 425 may prevent freefalling objects from damaging the vertical shaft and an oil plug at the bottom of the wellbore 150.

[0047] The CPSS 100 further includes an AC power regulator 420. For example, the AC power regulator 420 may interface an output power to be compatible with the power grid 120. For example, the output power may be compatible with the power grid 120 in phase, frequency, and voltage. In some implementations, the AC power regulator 420 may interface with a power interface of a renewable energy source 430 For example, the CPSS 100 may use the heavy-duty power equipment already installed in the renewable energy source 430 to advantageously reduce costs.

[0048] FIG. 5 is a flowchart illustrating an exemplary deployment method 500. For example, the CPSS 100 may be deployed with a crew of less than 12 people in one day. In this example, the method 500 begins when a power well container (e.g., the CPSS 100) is transported to a pre- selected location over a well in step 505. For example, the CPSS 100 may be loaded at a location over a wellhead. In step 510, a jib crane (e.g., the crane 110) is used to guide an assembly process of a drop weight. For example, the crane 110 may be used with a guide wire to install the weight rod 145 and to place the weight rod 145 into the wellbore 150. For example, the container may include an aperture in both upper and lower plane to provide a passage for the guide wire of the crane to pass through. At a decision point 515, it is determined whether the drop weight connection is secure. For example, the drop weight connection may be checked using the data/sensor module 185. If it is determined that the drop weight connection is not secure, in step 520, the drop weight connection is secured and the decision point 515 is repeated. For example, the steel cable connecting the weight rod 145 and the winch system 130 may be reinspected and fixed.

[0049] If it is determined that the drop weight connection is secure, in step 525, a controller of the power well container is connected to a cloud control system via a communication network. Next, in step 530, the power well container is connected to a power supply as input and a power grid as output, and the method 500 ends.

[0050] FIG. 6 is a flowchart illustrating an exemplary operation method 600. For example, the controller 155 may perform the operation method 600 to operate the CPSS 100 to store excess energy from the renewable energy source 430, and to meet excess demand by releasing energy to the power grid 120.

[0051] The method 600 begins when, in step 605, a control signal is received from a cloud control system. For example, the controller 155 may receive a control signal via the communication module 410. Next, at a decision point 610, it is determined whether the control signal is instructions to store energy. If it is determined that the control signal contains instructions to store energy, in step 615, a speed and height to lift a weight rod in a well is determined, based on the received signal, by a controller. Next, the weight rod is lifted at the determined speed to the determined height in step 620. For example, the controller 155 may control the motor system 415 and the gearbox 416 to lift the weight rod 145 at the determined speed.

[0052] If, in the decision point 610, it is determined that the control signal contains instructions to release energy, in step 625, based on the received signal, a speed and height to drop a weight rod in a well is determined by the controller. Next, in step 630, the weight rod is dropped at the determined speed to the determined height. For example, the controller 155 may control the speed by using the gearbox 416 so that the energy released may be captured efficiently.

[0053] After the weight rod is lifted (in step 615) or dropped (in step 625) to the determined height, at a decision point 635, it is determined whether any problem is detected during movement. For example, through one or more sensors, the controller 155 may detect whether the steel cable is stuck at any point in the wellbore 150. If it is determined that there is a problem during movement, at a decision point 640, it is determined whether an end signal is received. In the decision point 635, if it is determined that there is any problem during movement, in step 645, the problem is reported to the cloud control system, and the decision point 640 is repeated.

[0054] If, in the decision point 640, it is determined that the end signal is not received, the step 605 is repeated. If, in the decision point 640, it is determined that the end signal is received, the method 600 ends.

[0055] FIG. 7 depicts an exemplary weight rod 145 with a fishing grip. As shown, when the weight rod 145 descends at a speed higher than a predetermined speed, the fishing grip 700 may engage a wall of the wellbore 150 to slow down the weight rod 145. As depicted, the fishing grip 700 may be sloped such that, upon engagement of the fishing grip 700 by gripping elements (e.g., controllable and/or self-urging ‘fingers’), and a twisting motion of the gripping elements about a longitudinal axis of the weight rod 145, the gripping elements may releasably fixedly engage the weight rod 145 of the fishing grip 700. In some implementations, by way of example and not limitation, the fishing grip 700 may be used to lift, guide, and/or position the weight rod 145 and/or to prevent excessive velocity of the weight rod 145 (e.g., if a suspension cable breaks).

[0056] FIG. 8 depicts an exemplary weight rod 145 with a rod slip 800. In some implementations, the rod slip 800 may engage a wall of the wellbore 150 when there is an uncontrolled drop of the weight rod 145. For example, the rod slip 800 may pull the weight rod 145 by creating a frictional force at the wall.

[0057] In some implementations, the rod slip 800 may, for example, be coupled (e.g., directly, indirectly) to the wall of the wellbore 150 and may engage the weight rod 145 when there is an uncontrolled drop of the weight rod 145 (e.g., exceeding a predetermined velocity threshold, exceeding a predetermined stress due to friction between an engagement member of the rod slip 800 and the weight rod 145 and/or the wall of the wellbore 150).

[0058] FIG. 9 depicts an exemplary weight rod 145 with a deadline 190. In some implementations, the deadline 190 may be securely connected to the counteract system 425. As shown, a connection 905 between the weight rod and the winch system 130 breaks. The deadline 190 may hold the weight rod 145 in place to prevent further descend. In some implementations, the weight rod 145 may be forced to engage the wellbore 150 due to a connection point at a cable 910 with the deadline 190. For example, the engagement between the weight rod 145 and the wellbore 150 may further stabilize a position of the weight rod 145 and prevent further descent. In this example, a spring stopper 915 (e.g., a ‘stop plug’) is located above a well plug 920. The spring stopper 915, in the depicted example, engages (e.g., fixedly, relocatably) a wall of the wellbore 150. The spring stopper 915 may be configured to absorb and/or reduce kinetic energy from a fall (e.g., accidental) of the weight rod 145. Accordingly, the spring stopper 915 may be advantageously configured to prevent damage to the well plug 920 by falling objects. In some implementations, by way of example and not limitation, the spring stopper 915 may be implemented without the deadline 190, or vice versa.

[0059] Although various embodiments have been described with reference to the figures, other embodiments are possible. In some implementations, the controller 155 may transmit energy conversion data to the cloud system 405. For example, the cloud system 405 may apply the energy conversion data to train a machine learning model to fill excess demand of electricity more efficiently.

[0060] Although an exemplary system has been described with reference to FIGS. 1A-1C, other implementations may be deployed in other industrial, scientific, medical, commercial, and/or residential applications.

[0061] In various embodiments, some bypass circuits implementations may be controlled in response to signals from analog or digital components, which may be discrete, integrated, or a combination of each. Some embodiments may include programmed, programmable devices, or some combination thereof (e.g., PLAs, PLDs, ASICs, microcontroller, microprocessor), and may include one or more data stores (e.g., cell, register, block, page) that provide single or multi-level digital data storage capability, and which may be volatile, non-volatile, or some combination thereof. Some control functions may be implemented in hardware, software, firmware, or a combination of any of them.

[0062] Computer program products may contain a set of instructions that, when executed by a processor device, cause the processor to perform prescribed functions. These functions may be performed in conjunction with controlled devices in operable communication with the processor. Computer program products, which may include software, may be stored in a data store tangibly embedded on a storage medium, such as an electronic, magnetic, or rotating storage device, and may be fixed or removable (e.g., hard disk, floppy disk, thumb drive, CD, DVD).

[0063] Although an example of a system, which may be portable, has been described with reference to the above figures, other implementations may be deployed in other processing applications, such as desktop and networked environments.

[0064] Temporary auxiliary energy inputs may be received, for example, from chargeable or single use batteries, which may enable use in portable or remote applications. Some embodiments may operate with other DC voltage sources, such as batteries, for example. Alternating current (AC) inputs, which may be provided, for example from a 50/60 Hz power port, or from a portable electric generator, may be received via a rectifier and appropriate scaling. Provision for AC (e.g., sine wave, square wave, triangular wave) inputs may include a line frequency transformer to provide voltage step-up, voltage step-down, and/or isolation. [0065] Although particular features of an architecture have been described, other features may be incorporated to improve performance. For example, caching (e.g., LI, L2, ...) techniques may be used. Random access memory may be included, for example, to provide scratch pad memory and or to load executable code or parameter information stored for use during runtime operations. Other hardware and software may be provided to perform operations, such as network or other communications using one or more protocols, wireless (e.g., infrared) communications, stored operational energy and power supplies (e.g., batteries), switching and/or linear power supply circuits, software maintenance (e.g., self-test, upgrades), and the like. One or more communication interfaces may be provided in support of data storage and related operations.

[0066] Some systems may be implemented as a computer system that can be used with various implementations. For example, various implementations may include digital circuitry, analog circuitry, computer hardware, firmware, software, or combinations thereof. Apparatus can be implemented in a computer program product tangibly embodied in an information carrier, e.g., in a machine-readable storage device, for execution by a programmable processor; and methods can be performed by a programmable processor executing a program of instructions to perform functions of various embodiments by operating on input data and generating an output. Various embodiments can be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and/or at least one output device. A computer program is a set of instructions that can be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.

[0067] Suitable processors for the execution of a program of instructions include, by way of example, both general and special purpose microprocessors, which may include a single processor or one of multiple processors of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random-access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memories for storing instructions and data. Generally, a computer will also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and optical disks. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including, by way of example, semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, ASICs (application- specific integrated circuits).

[0068] In some implementations, each system may be programmed with the same or similar information and/or initialized with substantially identical information stored in volatile and/or non volatile memory. For example, one data interface may be configured to perform auto configuration, auto download, and/or auto update functions when coupled to an appropriate host device, such as a desktop computer or a server.

[0069] In some implementations, one or more user-interface features may be custom configured to perform specific functions. Various embodiments may be implemented in a computer system that includes a graphical user interface and/or an Internet browser. To provide for interaction with a user, some implementations may be implemented on a computer having a display device, such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor for displaying information to the user, a keyboard, and a pointing device, such as a mouse or a trackball by which the user can provide input to the computer.

[0070] In various implementations, the system may communicate using suitable communication methods, equipment, and techniques. For example, the system may communicate with compatible devices (e.g., devices capable of transferring data to and/or from the system) using point-to-point communication in which a message is transported directly from the source to the receiver over a dedicated physical link (e.g., fiber optic link, point-to-point wiring, daisy-chain). The components of the system may exchange information by any form or medium of analog or digital data communication, including packet-based messages on a communication network. Examples of communication networks include, e.g., a LAN (local area network), a WAN (wide area network), MAN (metropolitan area network), wireless and/or optical networks, the computers and networks forming the Internet, or some combination thereof. Other implementations may transport messages by broadcasting to all or substantially all devices that are coupled together by a communication network, for example, by using omni-directional radio frequency (RF) signals. Still other implementations may transport messages characterized by high directivity, such as RF signals transmitted using directional (i.e., narrow beam) antennas or infrared signals that may optionally be used with focusing optics. Still other implementations are possible using appropriate interfaces and protocols such as, by way of example and not intended to be limiting, USB 2.0, Firewire, AT A/IDE, RS-232, RS-422, RS-485, 802.11 a/b/g, Wi-Fi, Ethernet, IrDA, FDDI (fiber distributed data interface), token-ring networks, multiplexing techniques based on frequency, time, or code division, or some combination thereof. Some implementations may optionally incorporate features such as error checking and correction (ECC) for data integrity, or security measures, such as encryption (e.g., WEP) and password protection.

[0071] In various embodiments, the computer system may include Internet of Things (IoT) devices. IoT devices may include objects embedded with electronics, software, sensors, actuators, and network connectivity which enable these objects to collect and exchange data. IoT devices may be in-use with wired or wireless devices by sending data through an interface to another device. IoT devices may collect useful data and then autonomously flow the data between other devices.

[0072] Various examples of modules may be implemented using circuitry, including various electronic hardware. By way of example and not limitation, the hardware may include transistors, resistors, capacitors, switches, integrated circuits, other modules, or some combination thereof. In various examples, the modules may include analog logic, digital logic, discrete components, traces and/or memory circuits fabricated on a silicon substrate including various integrated circuits (e.g., FPGAs, ASICs), or some combination thereof. In some embodiments, the module(s) may involve execution of preprogrammed instructions, software executed by a processor, or some combination thereof. For example, various modules may involve both hardware and software.

[0073] In an exemplary aspect, a portable gravitational energy storage system (PGESS) may include a portable container having at least one aperture between an interior and exterior of the portable container. The PGESS may include multiple weight segments stowed in the portable container in a transport mode. The PGESS may include a folding crane coupled to the portable container and operable between a folded mode in which the crane is folded into a position substantially parallel with at least one surface of the portable container and an active mode in which the crane extends substantially vertically upwards from the portable container. The PGESS may include multiple electric motor-generators disposed in the portable container and each having a stator mechanically coupled to the portable container. The PGESS may include a transmission disposed in the portable container and mechanically coupled to transmit power to and receive power from at least one rotor of the multiple electric motor-generators, the transmission being provided with multiple selectable input to output ratios. The PGESS may include a rotating winching system disposed in the portable container and having a cable coupled to transmit power to and receive power from the transmission. The PGESS may include a controller configured to be coupled to an electric grid by an electric grid interface and to selectively operate the multiple motor-generators, the crane, the transmission, and the winching system based on signals received from the electric grid interface. When the portable container is transported by a vehicle to an electrical generation site and disposed over a vertical shaft, and field-deployed into a deployed mode, the crane is operated into the active mode and operates the multiple weight segments, wherein the folding crane is coupled to at least one weight segment by a guideline such that the crane guides the multiple weight segments within the vertical shaft as the multiple electric motor- generators translate the weight within the vertical shaft, such that the multiple weight segments are coupled together and disposed into the vertical shaft, then, the controller, based on the signals received from the electric grid interface, may selectively operate the transmission into one of the multiple selectable input to output ratios, and selectively operates the multiple electric motor- generators such that the multiple weight segments are selectively translated within the vertical shaft by the winching system in response to at least one of excess electrical generation and excess electrical demand of the electric grid.

[0074] The weight segments may be configured, in the deployed mode, to be fixedly coupled together into a single weight.

[0075] At least one of the multiple weight segments may be provided with a self-locking twist- lock collar configured to engage a locking element external to the weight segment when a downwards speed of the weight segments exceeds a predetermined threshold.

[0076] The multiple weight segments may be coupled together by a series of flexible joints. At least one of the flexible joints may be coupled to a deadline coupled externally to the vertical shaft such that, when a downward speed of the weight segments exceeds a predetermined threshold, the deadline causes the weight segments to destabilize and engage a wall of the vertical shaft.

[0077] The weight segments may include multiple recycled drill pipes.

[0078] The signals received from the electric grid interface may include network environmental data including a voltage, a frequency, and a phase of the electric grid. The controller may be configured to operate the multiple electric motor-generators, the crane, the transmission, and the winching system based on the network environmental data.

[0079] The PGESS may include a stop plug independently located above a plug of the vertical shaft, such that the plug is prevented from damage from falling objects.

[0080] In an exemplary aspect, an energy storage system may include a container having at least one aperture between an interior and exterior of the container. The energy storage system may include multiple weight segments stowed in the container in a transport mode. The energy storage system may include a folding crane coupled to the container and operable between a folded mode in which the crane is folded into a position substantially parallel with at least one surface of the container and an active mode in which the crane extends substantially vertically upwards from the container. The energy storage system may include at least one electric motor-generator disposed in the container, each at least one electric motor-generator having a stator mechanically coupled to the container. The energy storage system may include a transmission disposed in the container and mechanically coupled to transmit power to and receive power from at least one rotor of the at least one electric motor-generator, the transmission being provided with multiple selectable input to output ratios. The energy storage system may include a rotating winching system disposed in the container and having a cable coupled to transmit power to and receive power from the transmission. The energy storage system may include a controller configured to be coupled to an electric grid by an electric grid interface and to selectively operate the at least one electric motor- generator, the crane, the transmission, and the winching system based on signals received from the electric grid interface. When the container is transported by a vehicle to an electrical generation site and disposed over a vertical shaft, and field-deployed into a deployed mode, the crane is operated into the active mode and operates the multiple weight segments such that they are coupled together and disposed into the vertical shaft, then the controller, based on the signals received from the electric grid interface, may selectively operate the transmission into one of the multiple selectable input to output ratios, and may selectively operate the at least one electric motor- generator such that the multiple weight segments are selectively translated within the vertical shaft by the winching system in response to at least one of excess electrical generation and excess electrical demand of the electric grid.

[0081] The at least one electric motor-generator may include multiple through-shaft electric motor-generators coupled together in-line and to the transmission by at least one shaft.

[0082] The multiple weight segments may be configured, in the deployed mode, to be fixedly coupled together into a single weight.

[0083] During operation of the multiple weight segments, the crane may be coupled to at least one weight segment by a guideline such that the crane guides the weight within the vertical shaft as the at least one electric motor-generator translates the weight within the vertical shaft.

[0084] At least one of the weight segments may be provided with a self-locking twist-lock collar configured to engage a locking element external to the weight segment when a downwards speed of the weight segments exceeds a predetermined threshold.

[0085] The weight segments may be coupled together by a series of flexible joints and at least one of the flexible joints is coupled to a deadline coupled externally to the vertical shaft such that, when a downward speed of the weight segments exceeds a predetermined threshold, the deadline causes the weight segments to destabilize and engage a wall of the vertical shaft.

[0086] The weight segments may include recycled drill pipes.

[0087] The signals received from the electric grid interface may include network environmental data including a voltage, a frequency, and a phase of the electric grid. The controller may be configured to operate the at least one electric motor-generator, the crane, the transmission, and the winching system based on the network environmental data. [0088] The energy storage system may include a stop plug independently located above a plug of the vertical shaft, such that the plug is prevented from damages from falling objects.

[0089] The vehicle may include a roller-bed trailer. The container may include a multi-modal shipping container. More than one of the containers may be simultaneously transported by the vehicle.

[0090] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. For example, advantageous results may be achieved if the steps of the disclosed techniques were performed in a different sequence, or if components of the disclosed systems were combined in a different manner, or if the components were supplemented with other components. Accordingly, other implementations are contemplated within the scope of the following claims.