WO2025171374A1 - Renewable energy hydrofoils for water flow hydrokinetics and related systems and methods thereof - Google Patents

Abstract

The present invention relates to a renewable energy system designed to harness hydrokinetic energy from riverine environments using bio-inspired hydrofoil mechanisms. The system comprises a pair of hydrofoils configured to oscillate out-of-phase in response to water flow, a mechanical motion rectifier to convert oscillatory motion into unidirectional rotary motion, and a generator to produce electrical energy. A support structure stabilizes the components, while a control system optimizes energy generation by adjusting hydrofoil pitch angles and oscillation parameters based on sensory feedback. This innovative approach offers a scalable, efficient, and environmentally friendly solution for riverine hydrokinetics, minimizing ecological impact and adapting to varying site conditions.

Description

RENEWABLE ENERGY HYDROFOILS FOR WATER FLOW HYDROKINETICS AND RELATED SYSTEMS AND METHODS THEREOF

CROSS REFERENCE TO RELATED APPLICATION

This application is related to and claims the benefit of U.S. Provisional Application Number 63/522,029 filed on February 09, 2024, the entire contents of which are herein incorporated by reference.

STATEMENT OF GOVERNMENT INTEREST

This invention was made with government support under DE-AR0001 42 awarded by the U.S. Department of Energy. The government has certain rights in the invention.

TECHNICAL FIELD

The field of the invention pertains to renewable energy technologies, specifically focusing on hydrokinetic systems for energy generation from flowing water bodies such as rivers. It involves the design and implementation of bio-inspired hydrofoil mechanisms that convert the kinetic energy of water flow into electrical energy, emphasizing adaptability, efficiency, and minimal environmental impact.

BACKGROUND

In recent years, the demand for renewable energy sources has intensified, driven by the need to reduce reliance on fossil fuels and mitigate environmental impacts. Among the various renewable energy technologies, hydrokinetic systems have emerged as a promising solution for harnessing energy from flowing water bodies such as rivers and tidal environments. However, conventional hydrokinetic systems, such as traditional rotary turbines, often face significant challenges. These include high installation and maintenance costs, environmental disturbances due to high tip speeds, and the potential for negative impacts on aquatic ecosystems. Additionally, the efficiency of these systems can be limited by their inability to adapt to varying flow conditions, and river depths and width, which can result in suboptimal energy generation.

Existing solutions in the field of riverine hydrokinetics often struggle with scalability and adaptability to different site conditions. Many systems require substantial structural modifications to accommodate site-specific requirements, leading to increased costs and complexity. Furthermore, the environmental footprint of these systems can be considerable, as they may disrupt sediment patterns and aquatic habitats. There is a pressing need for a more adaptable, efficient, and environmentally friendly approach to riverine hydrokinetics that can overcome these limitations and provide a sustainable energy solution.

BRIEF SUMMARY

A simple, resilient, and scalable solution of renewable energy hydrofoils, among other things, is proposed. By adapting the concept of biological unsteady lift, an aspect of an embodiment of the present invention centers on pairs of out-of-phase oscillating hydrofoils placed into oncoming flow. The river flow causes the two foils to oscillate in opposite directions. Separating these hydrofoils is an energy conversion with a mechanical motion rectifier that converts the oscillatory linear motion of the foils to unidirectional rotary motion with high efficiency/reliability and minimal mass. In an embodiment, the hydrofoils and generator will be supported via a lightweight column and an anchor and cable system, optimized for minimum mass. An aspect of an embodiment of the present invention is, among other things, the integration of fin pitch and torque controls to ensure optimality or near optimality for energy generation with minimal complexity. In an embodiment, sensory feedback control can be used to ensure that pitch angles, heave waveform and velocity are optimized for current flow conditions of the operating environment to maximize energy capture (analogous to fish having high efficiency swimming over a wide range of velocities) as well as reduce structural load (balance the fins) to reduce mass. This bio-inspired solution can improve energy generation in riverine and tidal environments. An aspect of an embodiment of the present invention provides a system configured for and/or a method for using, among other things, renewable energy hydrofoils for highly-efficient low-cost riverine and tidal hydrokinetics.

An aspect of an embodiment of the present invention provides a system configured for and/or a method for using, among other things, bio-inspired renewable energy (BIRE) for highly-efficient low-cost riverine and tidal hydrokinetics.

An aspect of an embodiment of the present invention provides a system configured for and/or a method for using, among other things, renewable energy hydrofoils for riverine and tidal hydrokinetics or the like.

An aspect of an embodiment of the present invention provides a method for, among other things, manufacturing renewable energy hydrofoils for riverine and tidal hydrokinetics.

An aspect of an embodiment of the present invention provides an article of manufacture or composition comprising, among other things, renewable energy hydrofoils for riverine and tidal hydrokinetics

An aspect of various embodiments of the present invention may provide a number of advantages, such as but not limited thereto, the following:

• Modular design of the device allows for adaptability for different site locations for which we can optimize with co-control design for the specific site without needing the significant change in the mechanical design.

• Reduced environmental impact (compared to conventional turbines) due to low tip speeds (which minimizes noise generation and sediment dispersion downstream) and no bathymetry impact (which minimizes structure signature on the basin) BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts, in which:

FIG. 1 is a schematic representation of a renewable energy hydrofoil system in one embodiment of the invention;

FIG. 2 is another schematic representation thereof;

FIG. 3 is another schematic representation thereof;

FIG. 4 is a schematic representation of a bio-inspired hydrofoil having a flexible tail;

FIG. 5-11 show various exemplary embodiments of hydrofoil mechanisms and power take-off arrangements according to the invention;

FIGS. 12A-B shows another embodiment of a hydrofoil mechanism having a rack and pinion power take-off arrangement;

FIGS. 13A-B show partial enlarged views of the power take-off arrangement of FIGS. 12A-B;

FIG. 14 shows a hydrofoil mechanism having a ball screw power take-off arrangement;

FIGS. 15-16 show a partial enlarged view of the ball screw power take-off arrangement of FIG. 14;

FIG. 17 shows another view of the hydrofoil mechanism of FIG. 14 including a pitch control mechanism;

FIG. 18 is a schematic view of the pitch control mechanism and power take-off arrangement of FIG. 17; FIG. 19 shows a renewable energy hydrofoil system in a further embodiment of the invention;

FIG. 20 shows various hydrofoils according to the invention;

FIG. 21 shows another embodiment of a hydrofoil mechanism having pulley and belt power take-off arrangement;

FIG. 22 shows a partial enlarged view of the power take-off arrangement of FIG. 21; and

FIGS . 23 A-C show yet another embodiment of a hydrofoil mechanism having pulley and belt power take-off arrangement.

DETAILED DESCRIPTION

FIGS. 1-2 show exemplary schematic representations of a renewable energy hydrofoil system 10 in one embodiment of the invention. The system 10 includes a plurality of hydrofoil mechanisms 12 that are modular in nature and, as such, can be combined in a vertical and/or horizontal array, in accordance to conditions of a particular waterway.

For example, as shown in FIG. 1, two hydrofoil mechanisms 12 are arranged vertically, one atop the other, in a river A having a flow velocity U. Each hydrofoil mechanism 12 has at least one foil 14 disposed so as to oscillate along a vertical axis V in response to the flow U of the river A. That is, the foil 14 is a wing shaped element designed to create a pressure differential between a top and bottom side as the river flow U passes around the foil 14. The foil 14 is arranged to pivot about a horizonal axis H perpendicular to the vertical axis V such that the angle of attack of the foil 14 changes to result in an oscillation of the foil 14 along the vertical axis V. Particularly, the mechanism 12 is configured to pivot the foil 14 at the top and the bottom of a heave range of the foil 14 so as to change the attack angle, thus reversing the direction of movement of the foil 14 along the vertical axis V and creating the oscillation. The mechanism 12 includes a generator which is driven by the oscillation of the foils 14. The generator converts the movement of the hydrofoils 14 into electrical energy.

The modular nature of the renewable energy hydrofoil system 10 allows for adaptation to different and varying river depths and widths. For example, the average depth of the river A in FIGS. 1-2 is 2.4m, with a depth range of 1.5 to 3.3m. Each exemplary hydrofoil mechanism 12 has a heave range of about 0.3m to about 1.2m. A gap of about 0.1m is preferred between stacked foils 14 in order to prevent unwanted contact of adjacent foils 14 and to minimize undesired turbulence. Therefore, in this example, the two hydrofoil mechanisms 12 have a heave range of about 0.7m to about 2.5m. With the depth of the river at 2.4m, the heave range of the staked foils 14 is set to 0.75m with the gap therebetween of 0.1m. Thus, the effective sweep heigh of the foils 14 is 1 ,5m, leaving a top / bottom clearance of 0.4m. As the depth of the river A varies, the heave range of the foils 14 can be enlarged or reduced accordingly. Operation of the upper foil 14 can be ceased all together if the depth of the river A drops beneath a level necessary for generating the oscillatory motion.

As shown in FIG. 2, the hydrofoil mechanisms 12 may be supported by power struts 16 which are fixed on the riverbed surface or beneath, and include facilities for power take off and for shoreline transmission of the generated electrical energy.

FIG. 3 shows a schematic representation of a cross-section of a portion of the river A and illustrates the flexible and modular nature of the renewable energy hydrofoil system 10. The number, height, width, and operation of the hydrofoil mechanisms 12 can be tailored to fit the river site conditions. For example, in deeper areas of the river (left in FIG. 3), the system may include two stacked hydrofoil mechanisms 12 oscillating in their maximum foil sweep range. In the shallower areas of the river (right in FIG. 3), the system 10 may include shorter power struts 16 and dual stacked hydrofoil mechanisms 12 having smaller foil heave ranges, or instead, single hydrofoil mechanisms 12 rather than stacked. The heave range of the foils 14 can be varied to accommodate different flows and depths of the river. For example, larger heave range can be utilized in the deeper areas of the river while smaller heave range are used in the shallow areas. This increases the effective swept area and so increases the available energy from the water flow, while minimizing impact on aquatic wildlife. Also the width of the foils 14 can be adjusted to meet riverine conditions.

FIG. 4 shows an embodiment of the renewable energy hydrofoil system 10 which comprises foils 14 each having a front end facing toward the river flow U and an opposite rear end, where the rear end is flexible and forms a soft tail. The soft tail allows for a deflection at the top and bottom of the oscillation of the respective foils 14. This deflection provides an increased clearance between the vertically stacked foils 14, such that the gap distance required therebetween is reduced. Moreover, the soft tail minimizes any damage thereof by contacting adjacent tails or the river bottom. Accordingly, the required gap distance between stacked foils and between foils and the river bottom may be reduced, thus increasing efficiency and overall power generation of the system 10. Such soft tails also minimize impact on aquatic wildlife as damage through physical contact is reduced by virtue of the softer, flexible nature of the foil tails. Additionally, the soft tails may be tuned to give a bio-inspired time-dependent camber which improves maximum lift generated by the foils 14.

FIGS. 5-6 shows an exemplary embodiment of a renewable energy hydrofoil system 20 having two foils 14 each having an arm 22 affixed pivotally via a roller 24 to the power stmt 16. The two foils 14 are arranged to oscillate out of phase when subjected to the flow U of the river A. A mechanical motion rectifier (MMR) 26 is communicatively engaged with the rollers 24 and converts the oscillating rotation of the hydrofoils 14 into unidirectional rotation with high efficiency and low maintenance. This unidirectional motion is then transferred to a generator 28 to produce electrical energy. Bevel gears 30 couple the out-of-phase oscillations of the two hydrofoils and speed up the rotation, transferring the rotational energy to the MMR 26, as discussed in detail further herein.

In another embodiment of the mechanism 20, FIGS. 7-8 show two hydrofoils 14 arranged vertically along the power strut 16 and rotationally connected thereto via the rollers 24. In this example, the MMR 26 has a compact design and utilizes a ball screw arrangement and a series of gears, as discussed further herein, to convert the out-of-phase oscillatory motion of the foils 14 to unidirectional motion which is transferred to the generator for electricity production.

FIG. 9 shows another exemplary embodiment of the renewable energy hydrofoil system 20 in which the two foils 14 arc again affixed to the arms 22 which arc pivotable relative to the power strut 16 via the rollers 24. However, here, the rotation of the rollers 24 generated by oscillation of the foils 14 is transferred to the MMR by arcs 32 which directly engaged and rotate the MMR. Each arc 32 may be a curved rack pinon or a belt or some similar structure sufficient for translating the high speed rotation of the roller 24 to rotational movement of the MMR. This embodiment may avoid use of a gearbox, thus simplifying assembly and maintenance.

FIGS. 10-11 show yet another embodiment of the mechanism 20 having an alternate means of deriving power from the oscillating foils 14. Here, the oscillation of the foils 14 rotates a crankshaft 34 which drives a piston 36 to engage the MMR, or the generator directly, in order to generate electricity.

FIG. 12A shows a hydrofoil mechanism system 12 in an exemplary embodiment including a single hydrofoil 14 arranged for oscillatory motion along the vertical axis V where the power strut 16 includes two tracks, one on either side of the foil 14 which engage the foil 14 and guide the vertical motion. A central beam 38 connects the foil 14 to the MMR 26 which is disposed at a top of the power strut 16. The oscillation of the foil 14 is transferred to the MMR 26 by the central beam 38.

In one embodiment, as shown in FIGS. 12A-B and 13A-B, the MMR 26 comprises a double rack and pinion system including parallel first and second racks 40, 42 and corresponding first and second pinions 44, 46 contained within a gearbox 48. The first and second racks 40, 42 are connected to the central beam 38 and thus move with the vertical oscillatory motion of the foils 14. The first rack 40 engages the first pinion 44 and rotates the same on the up stroke of the foil 14. The second rack 42 engages the second pinion 46 and rotates the same on the down stroke of the foil 14. The pinions 44, 46 engage a shaft 50 of the MMR 26, each through a one-way clutch 52 which permits only one of the pinons 44, 46 to rotate the shaft 50 at a time. Thus, during the up stroke of the foil 14, the first pinion 44 is engaged with the first rack 40 by the clutch 52. The shaft 50 then rotates in the corresponding direction. Similarly, during the down stroke, the clutch 52 engages the second pinion 46 is engaged with the second rack 42 and hence rotates the shaft 54 in the opposite direction. A gear assembly 49 converts the bidirectional oscillatory motion of the shaft 54 into uni-directional rotation which then spins the generator 28 in order to produce electrical energy.

FIGS. 14-16 show an alternate version of the hydrofoil mechanism 12 having an MMR 26 with a ball screw system. Herein, the mechanism 12 includes a push tube 54 connected on one end to the central beam 38 and on the other end to a ball screw 56. As described above, as the foil 14 oscillates upward and downward in the river flow U, the central beam 38 is correspondingly driven up and down along the vertical axis V. In this embodiment, the push tube 54 moves in correspondence with the central beam 38 and rides over the ball screw 56. Due to the nature of the engagement of the push tube 54 and the ball screw 56, the linear movement of the former imparls a rotational movement on the latter. The MMR 26 at an upper extent includes an end support 58 which connects the ball screw 56 to a gear box 60 in such a manner that the ball screw 56 is free to rotate relative to the gear box 60. First and second ball shaft pinions 62, 64 are disposed within the gearbox 60 on a shaft extension of the ball screw 56 such that the pinions 62, 64 rotate with the rotation of the ball screw 56. During an up stroke of the foil 14, the ball screw 56 rotates in one direction, while, during a down stroke of the foil 14, the ball screw 56 rotate in the opposite direction. Each of the first and second pinions 62, 64 includes a one way clutch 66 which engages only one of the pinions 62, 64 to the ball screw 56 during the up stroke of the foil 14, and then which engages only the other of the pinions 62, 64 during the down stroke. The first and second ball shaft pinions 62, 64 are meshed with a generator pinion 68 which drives the generator 28 to produce electrical energy.

In this arrangement, during an up stroke of the foil 14, the ball screw 56 rotates in the first direction and spins the first pinion 62 which is brought into engagement therewith by the respective one-way clutch 66. The rotation of the ball screw 56 is thus transferred to the first pinion 62 and then to the meshed generator pinion 68 and ultimately to the generator 28 which converts the rotational energy to electrical energy. Similarly, during the down stroke of the foil 14, the ball screw 56 rotates in the opposite second direction and spins the second pinion 64 which is brought into engagement therewith by the respective one-way clutch 66. In this way, the rotation of the ball screw 56 is thus transferred to the second pinion 64 and then to the meshed generator pinion 68 and ultimately to the generator 28 for electrical energy production.

FIG. 17 provides another view of the hydrofoil mechanism 12 of FIG. 12 having the double rack and pinion MMR arrangement. Here, the mechanism 12 further includes a pitch control mechanism 70 which is configured to sense and adjust the pitch of the foil 14 in response to river conditions and/or desired energy generation goals. FIG. 18 is a schematic of the mechanism 12 of FIG. 17 in which the pitch control mechanism 70 is shown to include a servo motor 72 which rotates the foil 14 about the pitch axis P while the mechanism 12 allows for the above described oscillation along the vertical axis V. For example, as the river flow U decreases, pitch angle may be increased in order to maintain a desired heave range. The pitch control mechanism 70 may be controlled via computer or other user interface connected either wirelessly or wired.

FIG. 19 shows a bio-inspired renewable energy (BIRE) system 100 in one exemplary embodiment. The system 100 is intended to maximize energy generation efficiency, even when subjected to non-ideal inflow hydrodynamics, in a scalable manner while providing a low noise signature, a low structural signature, and minimum negative impact upon the aquatic ecosystem. In the illustrative example, a hydrofoil mechanism 102 resembles that disclosed above with regard to FIGS 5-8 and includes a plurality of hydrofoils 104 disposed at one end of arms 106 which, at opposite ends, connect to the previously disclosed MMR 26 which transfers oscillatory motion of the foils 14 to the generator 28 in one or more of the manners described herein. An upstream anchor 108 renders the mechanism 102 stationary on the river bed. The system 100 is subject to turbulent inflow having a distributed riverine velocity profile 112. The power strut 16 includes upstream flow sensors 114 to detect changes in riverine flow velocity. Additional sensors 114 may be disposed on one or more of the foils 14 in order to detect pressure and/or flow characteristics. Pitch and heave range of the foils 14 is controllable as discussed above. The foils 14 include an optimized hydrofoil cross-sectional profile and may include the soft tail described above. The heave range of the foils 14 is optimized for synergistic out of phase interactions and for a non-sinusoidal trajectory.

FIG. 20 shows exemplary foils 14. The foil in the right of the illustration includes end plates and has a thickness of about 25% greater than the thickness of the foil 14 on the left.

FIG. 21 depicts another exemplary embodiment of a hydrofoil mechanism 150 for use in a renewable energy hydrofoil system according to the present disclosure. FIG. 22 illustrates an enlarged partial schematic of the mechanism 150, particularly showing the connection and interaction of the various elements of the mechanism 150.

As shown, the mechanism 150 includes a two hydrofoils 14 each having a shaft 152 extending through a length thereof, from one end of the respective hydrofoil 14, to the other opposite end. A rotary bearing 154 is disposed on the hydrofoil shaft 152 at both ends thereof to allow for rotation of the foil 14 about the axis of the shaft 152 in order to enable pitch adjustment. A pitch control mechanism 70 is disposed at least at one end of the hydrofoil shaft and is configured to detect current pitch angle of the hydrofoil 14 and to make adjustments thereto as desired. A mounting bracket 156 is also disposed at both ends of the hydrofoil shaft 152 and serves to connect the shaft 152 to left and right columns 158 which each extend vertically and parallel to one another. Linear bearings 160 may be used to secure the mounting brackets 156 to the columns 158 in the horizontal direction, but still allow for movement of the foils 14 in the vertical plane formed by the columns 158. That is, the columns 158 are fixed and stationary in the hydrofoil mechanism 150, but the hydrofoils 14 are slidably movable thereon so that they are free to perform the oscillatory motions described herein. A clamp 162 is engaged to each opposite ends of the hydrofoil shaft 152. Each of said clamps 162 is further engaged to a belt 164 which forms an endless loop about a pair of pullies 166 disposed outwardly adjacent of the left and right columns 158. In this way, as the foils 14 oscillate up and down along the columns 158, the foils 14 simultaneously drive the belts 164 around the pullics 166.

On the left column 158, one of the pullies 166 is disposed toward a top and another pulley 166 is disposed at the bottom. The belt 164 loops around the top and bottom pullics 166 so that a portion of the belt 164 is disposed forward, while a portion of the belt is disposed rearwardly, both portions being parallel to one another. The pullies 166 and the belt 164 are arranged similarly on the right column 158. One of the foils 14 is affixed, in the manner described above, to the forward portion of the left and right belts 164, while the other foil 14 is affixed to the rearward portions of the belts 164. This allows for the reciprocal oscillatory movement of the foils 14 while still each being attached to the same endless loop belts 164. That is, when the upper foil 14 moves in the upward direction, the lower foil 14 moves in the downward direction, and vice versa.

At the top of the columns 158, the pullies 166 are attached to an output shaft 168. As the belts 164 reciprocate in response to the oscillation of the foils 14, the output shaft 168 rotates in one direction and then the opposite. The output shaft 168 may be connected to the MMR 26 and the generator 28 by any of the means discussed herein for transforming bi-directional movement into uni-directional movement which is then converted by the generator to electrical energy.

A truss frame 170 is affixed to the columns 158 on a downstream side to support the generator 28 and other components of the mechanism 150 and to provide structural strength and rigidity.

FIGS. 23A-C show another embodiment of the hydrofoil mechanism 150 which further includes a belt tensioning mechanism 172 which maintains a desired tension upon the belts 164 in order to enhance efficiency.

Systems, methods, and mechanisms of efficient renewable energy generation through riverine hydrokinetics are provided herein that are scalable and adaptable to different site conditions, are less complex and less expensive to install and maintain, with a reduced environmental footprint and less disruption to sediment patterns, aquatic habitats, and animals, thus addressing and solving the problems of the prior art. Although example embodiments of the present disclosure are explained in some instances in detail herein, it is to be understood that other embodiments arc contemplated. Accordingly, it is not intended that the present disclosure be limited in its scope to the details of construction and arrangement of components set forth in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways.

It should be appreciated that any element, part, section, subsection, or component described with reference to any specific embodiment above may be incorporated with, integrated into, or otherwise adapted for use with any other embodiment described herein unless specifically noted otherwise or if it should render the embodiment device nonfunctional. Likewise, any step described with reference to a particular method or process may be integrated, incorporated, or otherwise combined with other methods or processes described herein unless specifically stated otherwise or if it should render the embodiment method nonfunctional. Furthermore, multiple embodiment devices or embodiment methods may be combined, incorporated, or otherwise integrated into one another to construct or develop further embodiments of the invention described herein.

It should be appreciated that any of the components or modules referred to with regards to any of the present invention embodiments discussed herein, may be integrally or separately formed with one another. Further, redundant functions or structures of the components or modules may be implemented. Moreover, the various components may be communicated locally and/or remotely with any user/operator/customer/client or machine/system/computer/processor. Moreover, the various components may be in communication via wireless and/or hardwire or other desirable and available communication means, systems and hardware. Moreover, various components and modules may be substituted with other modules or components that provide similar functions.

It should be appreciated that the device and related components discussed herein may take on all shapes along the entire continual geometric spectrum of manipulation of x, y and z planes to provide and meet the environmental, anatomical, and structural demands and operational requirements. Moreover, locations and alignments of the various components may vary as desired or required.

It should be appreciated that various sizes, dimensions, contours, rigidity, shapes, flexibility and materials of any of the components or portions of components in the various embodiments discussed throughout may be varied and utilized as desired or required.

It should be appreciated that while some dimensions are provided on the aforementioned figures, the device may constitute various sizes, dimensions, contours, rigidity, shapes, flexibility and materials as it pertains to the components or portions of components of the device, and therefore may be varied and utilized as desired or required.

It must also be noted that, as used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value.

When such a range is expressed, other exemplary embodiments include from the one particular value and/or to the other particular value.

By “comprising” or “containing” or “including” is meant that at least the named compound, element, particle, or method step is present in the composition or article or method, but does not exclude the presence of other compounds, materials, particles, or method steps, even if the other such compounds, material, particles, or method steps have the same function as what is named.

In describing example embodiments, terminology will be resorted to for the sake of clarity. It is intended that each term contemplates its broadest meaning as understood by those skilled in the art and includes all technical equivalents that operate in a similar manner to accomplish a similar purpose. It is also to be understood that the mention of one or more steps of a method does not preclude the presence of additional method steps or intervening method steps between those steps expressly identified. Steps of a method may be performed in a different order than those described herein without departing from the scope of the present disclosure. Similarly, it is also to be understood that the mention of one or more components in a device or system docs not preclude the presence of additional components or intervening components between those components expressly identified.

Some references, which may include various patents, patent applications, and publications, are cited in a reference list and discussed in the disclosure provided herein. The citation and/or discussion of such references is provided merely to clarify the description of the present disclosure and is not an admission that any such reference is “prior art” to any aspects of the present disclosure described herein. In terms of notation, “[n]” corresponds to the n^lh reference in the list. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference was individually incorporated by reference.

The term “about,” as used herein, means approximately, in the region of, roughly, or around. When the term “about” is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values set forth. In general, the term “about” is used herein to modify a numerical value above and below the stated value by a variance of 10%. In one aspect, the term “about” means plus or minus 10% of the numerical value of the number with which it is being used. Therefore, about 50% means in the range of 45%-55%. Numerical ranges recited herein by endpoints include all numbers and fractions subsumed within that range (e.g. I to 5 includes 1, 1.5, 2, 2.75, 3, 3.90, 4, 4.24, and 5). Similarly, numerical ranges recited herein by endpoints include subranges subsumed within that range (e.g. 1 to 5 includes 1- 1.5, 1.5-2, 2-2.75, 2.75-3, 3-3.90, 3.90-4, 4-4.24, 4.24-5, 2-5, 3-5, 1-4, and 2-4). It is also to be understood that all numbers and fractions thereof are presumed to be modified by the term “about.”

Additional descriptions of aspects of the present disclosure will now be provided with reference to the accompanying drawings. The drawings form a part hereof and show, by way of illustration, specific embodiments or examples.

Claims

CLAIMS What is claimed is:

1. A system for generating renewable energy from riverine hydrokinetics, comprising: a pair of hydrofoils configured to oscillate out-of-phase in response to water flow, each hydrofoil having a wing-shaped element designed to create a pressure differential as water flows around it; a mechanical motion rectifier operatively connected to the hydrofoils, configured to convert the oscillatory linear motion of the hydrofoils into unidirectional rotary motion; a generator coupled to the mechanical motion rectifier, configured to convert the unidirectional rotary motion into electrical energy; a support structure configured to position and stabilize the hydrofoils and generator in a riverine environment; and a control system configured to adjust the pitch angles and oscillation parameters of the hydrofoils based on sensory feedback, optimizing energy generation efficiency and reducing structural load.

2. The system of claim 1, wherein the hydrofoils are bio-inspired and include flexible tails to enhance oscillation efficiency and reduce impact on aquatic wildlife.

3. The system according to any of the previous claims, wherein the mechanical motion rectifier includes a double rack and pinion system to convert oscillatory motion into unidirectional rotary motion with high efficiency.

4. The system according to any of the previous claims, wherein the control system includes sensors configured to detect water flow velocity and adjust the pitch angles of the hydrofoils accordingly to maintain optimal energy generation.

5. The system according to any of the previous claims, wherein the support structure is modular, allowing for adaptation to varying river depths and widths without significant structural modifications.

6. The system according to any of the previous claims, wherein the generator is configured to operate with low noise emissions to minimize environmental disturbance.

7. The system according to any of the previous claims, further comprising a power take-off arrangement selected from the group consisting of a ball screw, a crankshaft, and a pulley and belt system, configured to transfer energy from the hydrofoils to the generator.

8. The system according to any of the previous claims, wherein the hydrofoils are arranged in a vertical array to maximize energy capture from varying flow conditions in the riverine environment.