Wind powered hydroelectric power plant and method of operation thereof

• US 6,718,761 B2
• Filed: 04/05/2002
• Issued: 04/13/2004
• Est. Priority Date: 04/10/2001
• Status: Expired due to Term

• Current Assignee: New World Generation Inc. (BluForest, Inc.)
• Original Assignee: New World Generation Inc. (BluForest, Inc.)
• Inventors: Merswolke, Paul H. F., Gardner, Thomas B.
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Leslie, Michael
• Application Number:
  US10/116,006
• Publication Number:
  US 20020144504A1
• Time in Patent Office: 739 Days
• Field of Search: 603/98, 604/18, 91/4.R, 417/334, 290/44, 290/55
• US Class Current: 60/398
• CPC Class Codes: F03B 13/06 Stations or aggregates of water-storage type, e.g. comprising a turbine and a pumpturbines characterised by having means for functioning alternatively as pumps F03B3/10
• CPC Class Codes: F03D 1/02 having a plurality of rotors
• CPC Class Codes: F03D 9/008 the wind motor being combined with water energy converters, e.g. a water turbine
• CPC Class Codes: F03D 9/10 Combinations of wind motors with apparatus storing energy
• CPC Class Codes: F03D 9/17 storing energy in pressurised fluids
• CPC Class Codes: F03D 9/25 the apparatus being an electrical generator F03D9/22 takes precedence
• CPC Class Codes: F03D 9/28 the apparatus being a pump or a compressor
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids
• CPC Class Codes: Y02P 80/10 Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
• CPC Class Codes: Y02P 90/50 Energy storage in industry with an added climate change mitigation effect

Abstract

A hydroelectric power plant uses a plurality of windmills connected to compressed air generators to produce pressurized air. Pressurized air is used to drive water through a turbine to produce electrical power. The water is recycled and the power plant includes reserve pressurized air tanks to allow the plant to continue to operate when the wind levels are not sufficient to produce high pressure air. The power plant is designed to be operated on a continuous basis based on wind power. When the wind subsides and the reserve capacity has been exhausted, electricity can be drawn from the local utility supplier. When excess power is generated by the power plant, electricity from the power plant can be added to the grid of the local electricity supplier.

Claims

1. A hydroelectric power plant comprising a plurality of windmills connected to compressed air generators to provide pressurized air to a set of liquid storage tanks, said compressed air generators each having an air dryer to dry the compressed air produced by the air generator, each storage tank having a high pressure liquid outlet, a liquid inlet and an air inlet and air outlet, the liquid outlet of each storage tank being connected to a liquid inlet of a turbine that generates electricity when liquid passes through the turbine, the turbine having a liquid outlet and an electrical power outlet, the liquid outlet of the turbine being connected to a recycle line that is in turn connected to the liquid inlets of the storage tanks, a high pressure air reserve system to store high pressure air for use when wind velocities are not sufficient to operate the plant, said air reserve system having an air inlet and an air outlet, control means connected to control the transfer and distribution of pressurized air to the storage tanks, to control the flow of high pressure air to and from said air reserve system, to control the flow of high pressure liquid from the storage tanks to the turbine, and to control the recycling of liquid from the liquid outlet of the turbine to the liquid inlets of the storage tanks, said electrical power outlet of the turbine being connected to a power line, said liquid being water or mainly water.

2. A hydroelectric power plant as claimed in claim 1 wherein the said high pressure air reserve system is a container impervious to high pressure air selected from the group of a high pressure air storage tank, an underground cavern, a salt cavern, a calcitic cavern and a limestone cavern.

3. A hydroelectric power plant as claimed in claim 2 wherein air pressure on liquid flowing into the liquid inlet of the turbine is maintained at a substantially constant level.

4. A hydroelectric power plant as claimed in claim 2 wherein said control means causes the turbine to rotate at a substantially constant speed to produce 60 cycle electricity.

5. A hydroelectric power plant as claimed in claim 2 wherein the control means is a first controller connected to control the transfer and distribution of pressurized air to the liquid storage tanks, a second controller connected to control the flow of high pressure liquid from the liquid storage tanks to the turbine, a third controller connected to control the recycling of liquid from the liquid outlet of the turbine to the liquid inlet of the storage tanks, a fourth controller connected to control the transfer of electricity from the electrical power outlet of the turbine to the power line and a fifth controller connected to control the first, second, third and fourth controllers.

6. A hydroelectric power plant as claimed in claim 1 wherein each liquid storage tank is comprised of a primary storage tank and a secondary storage tank, said primary storage tank having an air inlet, an air outlet, a liquid inlet and a liquid outlet, said liquid outlet being connected to a liquid inlet of said secondary storage tank, said secondary storage tank having a liquid outlet in addition to a liquid inlet, said primary tank being connected to said secondary tank so that liquid leaving said primary tank enters said secondary tank, said primary tank always containing at least a minimum level of liquid therein, said secondary tank always being filled with liquid to prevent air from any of said primary storage tanks from entering said secondary storage tanks.

7. A hydroelectric power plant as claimed in claim 1 wherein the control means is connected to substantially empty each of the liquid storage tanks in succession while leaving a minimum level of liquid in each of said substantially empty liquid storage tanks so that air in the liquid storage tanks does not enter the turbine.

8. A method of operating a hydroelectric power plant using compressed air obtained from a plurality of windmills connected to compressed air generators, said plant having liquid storage tanks and a high pressure air reserve system, said method comprising producing pressurized air when the wind is blowing to operate compressed air generators connected to said windmills, storing excess compressed air produced by the windmills when the wind is blowing in the air reserve system for use when the wind is not blowing at a sufficient rate to operate the system, introducing the pressurized air into a plurality of storage tanks that are nearly filled with liquid, controlling the liquid outlet valves from each of the storage tanks to release high pressure liquid into an outlet line connected to the liquid inlet of a turbine, causing the liquid to flow into the turbine through the liquid inlet and out of the liquid outlet of the turbine, thereby generating electricity, pumping the liquid from the liquid outlet of the turbine back into the substantially empty liquid storage tanks, recharging the liquid storage tanks with high pressure air, repeating the method of releasing the liquid to the inlet of the turbine, pumping the liquid from the liquid outlet of the turbine and recharging the liquid storage tanks, and causing the electricity generated by the turbine to flow into a power line.

9. A method as claimed in claim 8 wherein the air pressure reserve system is a plurality of high pressure air reserve tanks, one or more underground caverns, a salt cavern, a calcitic cavern or a limestone cavern.

10. A method as claimed in claim 9 wherein the liquid is water or mainly water.

11. A method as claimed in claim 8 wherein the liquid storage tanks each comprise a primary liquid storage tank and a secondary liquid storage tank, each set of primary and secondary liquid storage tanks being connected so that liquid flowing out of the primary storage tank flows into the secondary storage tank and out of the secondary storage tank to the turbine, said method including the steps of controlling the level of liquid in the primary storage tanks so that the primary storage tanks substantially empty into the secondary storage tanks, the primary storage tanks always containing at least a minimum level of liquid and the secondary storage tanks always being filled with liquid.

12. A method as claimed in claim 11 wherein the liquid is water or mainly water.