IP Library › Granted Patent US 12,392,312
Granted Patent B2
US 12,392,312 · App. 17/662,355 · Granted Aug 19, 2025

Wave energy converter with pitch resonance tuning tanks and pneumatic turbines

Inventors: Adetoso Afonja (Blacksburg, VA); Stefano Brizzolara (Blacksburg, VA)
Assignee: VIRGINIA TECH INTELLECTUAL PROPERTIES, INC.
F03B13/142F03B13/24F05B2240/93
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Quick Facts
Patent No.
US 12,392,312
App. No.
17/662,355
Granted
Aug 19, 2025
Kind
B2
Abstract

In one or more embodiments, a wave energy converter comprises a floater that is buoyant in a body of water. The floater has a geometry such that the floater pitches in an angular motion about a transverse axis in response to an incoming wave in the body of water. The floater includes a tank that has a plurality of vertical columns. At least one of the vertical columns includes an air turbine. The tank stores a volume of fluid and a volume of air. The volume of fluid in the vertical columns is connected by at least one horizontal conduit. In response to the floater pitching due to the incoming wave, a motion of the volume of fluid between the plurality of vertical columns via the at least one horizontal conduit causes air to be released or admitted via the air turbine to generate electrical power.

Claims (36)

1. A wave energy converter, comprising:

a floater that is buoyant in a body of water, the floater having a geometry such that the floater pitches in an angular motion about a transverse axis in response to an incoming wave in the body of water; and

a tank in the floater having a plurality of vertical columns, a first vertical column of the plurality of vertical columns comprising a first air turbine, a second vertical column of the plurality of vertical columns comprising a second air turbine, the tank configured to store a volume of fluid and a volume of air, the plurality of vertical columns being connected by at least one horizontal conduit for movement of the volume of fluid between the plurality of vertical columns,

wherein in response to the floater pitching due to the incoming wave, a motion of the volume of fluid between the plurality of vertical columns via the at least one horizontal conduit causes air to be released or admitted via the first air turbine and the second air turbine to generate electrical power.

2. The wave energy converter of claim 1 , wherein the motion of the volume of fluid between the first vertical column and the second vertical column via the at least one horizontal conduit simultaneously causes the air to be released from the first vertical column via the first air turbine and the air to be admitted to the second vertical column via the second air turbine.

3. The wave energy converter of claim 1 , wherein the motion of the volume of fluid between the plurality of vertical columns via the at least one horizontal conduit causes air to be released from the first vertical column via the first air turbine based at least in part on an energetic frequency of the incoming wave.

4. The wave energy converter of claim 1 , wherein the first air turbine is configured to spin in a same direction in response to the air being released or admitted.

5. The wave energy converter of claim 1 , further comprising a device configured to at least:

add fluid to the volume of fluid in the tank from the body of water; or

discharge the fluid from the volume of fluid in the tank to the body of water.

6. The wave energy converter of claim 1 , wherein a distance or a size of the at least one horizontal conduit is selected based at least in part on a predicted energetic frequency of the incoming wave.

7. A method for converting kinetic energy of an incoming wave on a body of water to electrical energy, the method comprising:

determining at least one actual or predicted characteristic of the incoming wave;

based at least in part on the at least one actual or predicted characteristic, modifying a volume of fluid in a tank of a floater on the body of water, the floater being buoyant in the body of water, the floater having a geometry such that the floater pitches in an angular motion about a transverse axis in response to the incoming wave, the tank having a plurality of vertical columns, a first vertical column of the plurality of vertical columns comprising a first air turbine, a second vertical column of the plurality of vertical columns comprising a second air turbine, the tank storing the volume of fluid and a volume of air, the plurality of vertical columns being connected by at least one horizontal conduit for movement of the volume of fluid between the plurality of vertical columns; and

in response to the floater pitching due to the incoming wave, converting the kinetic energy of the incoming wave to the electrical energy by a motion of the volume of fluid in the tank causing air to be released or admitted via the first air turbine and the second air turbine.

8. The method of claim 7 , wherein modifying the volume of fluid in the tank further comprises pumping water from the body of water into the tank.

9. The method of claim 7 , wherein modifying the volume of fluid in the tank further comprises discharging fluid from the tank into the body of water.

10. The method of claim 7 , wherein modifying the volume of fluid optimizes converting the kinetic energy to the electrical energy.

11. The method of claim 7 , further comprising:

receiving data via a network indicating one or more parameters associated with a current location of the floater on the body of water; and

determining the at least one actual or predicted characteristic of the incoming wave based at least in part on the data.

12. The method of claim 7 , further comprising determining the at least one actual or predicted characteristic of the incoming wave based at least in part on a sensor of the floater.

13. The method of claim 7 , further comprising:

releasing the air from the first vertical column via the first air turbine; and

admitting the air to the second vertical column via the second air turbine.

14. The method of claim 7 , wherein a horizontal distance between the plurality of vertical columns is configured to optimize converting the kinetic energy to the electrical energy.

15. A wave energy converter, comprising:

a floater that is buoyant in a body of water, the floater having a geometry such that the floater pitches in an angular motion in response to an incoming wave in the body of water;

a tank in the floater having a plurality of vertical columns, the tank configured to store a volume of fluid and a volume of air the plurality of vertical columns being connected by at least one horizontal conduit for movement of the volume of fluid between the plurality of vertical columns; and

a first air turbine in a first vertical column of the plurality of vertical columns and a second air turbine in a second vertical column of the plurality of vertical columns,

wherein in response to the floater pitching due to the incoming wave, a motion of the volume of fluid between the first vertical column and the second vertical column via the at least one horizontal conduit causes air to be released via the first air turbine and the second air turbine to generate electrical power.

16. The wave energy converter of claim 15 , further comprising a respective air admittance valve for individual ones of the plurality of vertical columns.

17. The wave energy converter of claim 16 , further comprising a respective air admittance valve for individual ones of the plurality of vertical columns to control airflow between the individual ones of the plurality of vertical columns.

18. The wave energy converter of claim 17 , wherein the respective air admittance valves are configured to block airflow between a first vertical column of the plurality of vertical columns and allow airflow between a second vertical column of the plurality of vertical columns.

19. The wave energy converter of claim 18 , wherein the air is admitted via the respective air admittance valve of the first vertical column when the air is released from the second vertical column, and the air is admitted via the respective air admittance valve of the second vertical column when the air is released from the first vertical column.

20. The wave energy converter of claim 15 , wherein at least one of the first or the second air turbine is optimized for airflow being released.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 20, 2023
From: AFONJA, ADETOSO; BRIZZOLARA, STEFANO
To: VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY
Reel/Frame 063996/0909 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 20, 2023
From: VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY
To: VIRGINIA TECH INTELLECTUAL PROPERTIES, INC.
Reel/Frame 063996/0935 →
Continuity (2)
Provisional Application 63184888 · May 6, 2021
Related Publication 20220364541A1 · Nov 17, 2022
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