NL2001663C2 - Energy extraction system, has water pump attached to rotor, windmill for pumping water from sea, water system connected to water pump, for passing water pumped from sea, and generator connected to water system - Google Patents

Abstract

The system (1) has a water pump (4) attached to a rotor, and a windmill (2) for pumping water from a sea (3). A water system is connected to the water pump, for passing water pumped from the sea. A generator (6) is connected to the water system, for generating electrical energy from the pumped seawater. A basin is associated with the generator for storing the seawater, and includes a water output. A mast (14) is provided with a frame, and an electrical cable (22) conducts the generated electrical energy. An independent claim is also included for a method for generating energy.

Description

P84338NL00

Title; System and method for energy extraction

The invention relates to an energy extraction system provided with an offshore windmill placed at sea.

The invention also relates to a method for generating energy, wherein at sea a rotor of a windmill by wind. is driven 5.

It is known that offshore wind farms can make use of the relatively large amounts of wind and space that is present on the open sea for the conversion of wind energy into electrical energy. For example, these wind farms generate quantities of 200 to 500 10 MW per year.

A disadvantage of windmills used in such parks is that they are relatively expensive. Copper is often present in the generator, cables, for example switch-gear electricity cables, and / or electronics of the wind turbines. Due to varying wind speeds, the 15 windmills, for example, only provide energy for 3 to 50% of the time they are available. For the rest of the time, particularly when the wind is too low or too strong, the windmills stand still and the capacity of the windmill remains unused. As a result, the use of a wind turbine and / or a wind farm, and in particular the use of the relatively expensive copper, may not be profitable for a long time.

The relatively large amount of components in a wind turbine make the windmill very complex. The supporting construction of existing offshore wind turbines must also be of relatively heavy construction, since the head of the windmill is provided with a relatively heavy generator.

2

The object of the invention is therefore to offer an alternative to existing offshore wind turbines and / or wind farms, and / or to offer an alternative method for generating energy at sea.

This goal and / or other goals can be achieved with a system according to claim X.

This object and / or other objects can also be achieved with a method according to claim 18.

Further advantageous embodiments according to the invention are shown in the subclaims and will also be apparent from the description, in which the invention is further described in several exemplary embodiments with reference to the accompanying drawings. It shows:

Hg. 1 schematically an energy extraction system;

Hg. 2 also a transformer platform in a schematic manner. In this description, the same or corresponding parts have the same or corresponding reference numerals. In the drawing, only exemplary embodiments are shown. The elements used for this purpose are only given by way of example and should not be construed as being restrictive in any way. Figure 1 schematically shows an embodiment of an energy extraction system 1 with an offshore windmill 2. In this description, "offshore" can be understood to mean, for example, "at sea" or "at sea". The windmill 2 is placed in sea 3 and is equipped with a mechanically driven water pump 4. The pump 4 pumps in use Sea water from the sea via a water system 5 through the water system 5 towards a generator 6 which is driven by the pumped sea water . The pump 4 is preferably arranged in the head 7, also called gondola, of the windmill 2. The head 7 is also provided with a rotor 8, the shaft 9 of which is preferably arranged approximately horizontally and which rotor 8 is for instance provided with at least two vanes 10. Preferably, a drive shaft XI of the pump 4 extends approximately in line with the rotation axis 12 of the rotor shaft 9, and / or the drive shaft 11 is directly connected to the rotor shaft 9, and / or the rotor shaft 9 is part of the drive shaft .11, so that the pump 4 can advantageously be driven directly by the rotor shaft 9.

The water pipe system 5 is provided in at least one water pipe 13. The water pipe 13, for example, extends at least partially in the windmill mast 14 between the sea water and the pump 4, so that sea water from the sea 3 can be pumped through the windmill 2. The water pipe 13 for example, could also extend along or at least near the mast 14. For pumping up sea water, a first end part of the water supply system 5 extends below the surface 16 of the sea 3. In use, the sea water is pumped up through the water pipe 13 in a lift 17, and down through the pump 4 in a direction 13, and then towards the generator 6 for driving it.

For example, the mast 14 comprises a tubular structure or a frame 15 or the like. The mast 14 is preferably provided with a foundation or foot for anchoring the mill 2 in the seabed.

Between the windmill 2 and the generator 6, for example, a water pipe 19 extends, which preferably extends at least partly through and / or under and / or over the seabed 20. The generator 6 can for instance be arranged on a platform 21, which platform 21 is preferably positioned partly above the sea surface 16, for instance so that the generator 6 can be arranged at least partly above the sea surface 16. In another embodiment, the generator 6 is, for example, entirely or partially arranged under water. From the generator 6, for example, at least one electricity cable 22 extends through the seawater and / or, under and / or over the seabed 20 to carry the electrical energy generated by the generator 6 to land. A second end part of the water supply system 5 can ensure that the used seawater flows back into the sea 3.

4

This embodiment relates to an open water supply system in which sea water is pumped out of the sea 3 and flows back into the sea 3 after the generator 6 has been driven.

In another embodiment, the water system 5 relates, for example, to an at least partially closed system, wherein substantially the same sea water is pumped around more than once. After the seawater has passed the generator 6, it is again pumped around by the pump 4.

In a preferred modification of the system 1, the rotor 10 drives the pump 4, the pump 4 drives the seawater so that it flows through the water supply system 5, and the seawater flowing through the water supply system 5 ultimately drives the generator 6 for generation. of electrical energy.

In another embodiment, the system 1, in particular the water supply system 5, is provided with a basin 23 in which pumped seawater can be stored. A transformer platform 21 with a basin 23 thereon is shown schematically in Figure 2. Since the generator € is relatively heavy and / or large in comparison with conventional windmill generators, it is advantageous to place it on a separate platform 21. The platform 21 offers the possibility of approaching the generator 6 relatively easily for maintenance and / or changing of the generator 6. The basin 23 is, for example, coupled to the generator 6 by means of a water pipe outlet 24, so that seawater stored in the basin 23 can be used for driving the generator 6. The stored seawater can for instance flow through the outlet 24 to the generator 6 by means of gravity. The water supply system 5 is arranged such that the speed and / or pressure of the seawater that flowed out of the basin 23 can be enough to drive the generator 8 for generating electrical energy. A second water pump may also be provided at basin 23, for example, for increasing the speed or pressure, and / or the water may be driven in part by pump 4 already mentioned by rotor 8.

In one embodiment, the water supply system 5 is adapted to direct the pumped seawater directly along or through the generator 6 for driving it. To this end, for example, no basin 23 is provided, or, for example, a water diversion 25 is provided, which allows the seawater to pass through the basin 23, for example because the diversion 25 extends through the basin 23 or extends around the basin 23.

In one embodiment, the water supply system 5 at the front of 10 is a control 26 which is adapted to dose an amount of seawater that drives the generator 6. The controller 26 comprises, for example, a preprogrammed electrical circuit. The control 26 is, for example, adapted to guide at least a part of the pumped seawater into the basin 23 with a relatively high amount of pumped seawater, for example with a relatively large number of finds. In this description, relatively high wind can be understood to mean a relatively high wind speed. To this end, the water supply system 5 is for instance provided with a valve mechanism 27. When a relatively large amount of sea water is pumped through the water supply system 5, for example caused by a relatively large amount of wind, a part of the sea water, or all the sea water, in the basin 23 for later use, for example if the wind speed has decreased. To this end, the valve mechanism 27 is controlled, for example, by the controller 26 to guide at least a part of the seawater into the basin 23. For this purpose, the controller 26 receives for this purpose a signal from a measuring system that measures the speed and / or pressure of the seawater in the water supply system 5, and / or the speed and / or pressure of the seawater that drives the generator 6 and / or the quantity. generated energy by the generator 6. A choice can be made, for example, to allow a remaining part of the seawater to flow through the bypass 25, to be led directly to the 80 generator 6 and / or back into the sea.

6

In one embodiment, the control 26 is adapted to guide a certain amount from the basin 23 to the generator 6 at a relatively low amount of pumped seawater, for example in order to supply the generator 6 over a relatively long period of time with a relatively constant amount of seawater. be able to float with seawater from the basin 23. To that end, the water supply system 5 is provided, for example, with a second valve mechanism 28 which can cause the water to flow into the outlet 24, at least in an at least partially open state.

As is apparent from, inter alia, the above-described embodiments, the system 1 can be arranged such that the generator 6 is used in a constant manner during teletermined periods and / or so that peaks and troughs in the generated energy can be prevented. The amount of seawater that drives the generator 6 can also be dosed. In an embodiment, during long, relatively continuous periods, the maximum capacity of the generator 6 and / or the electricity cables 22 is utilized and / or a maximum or at least desired amount of electrical energy is generated.

In one embodiment, the water pipe system 5 and in particular the water pipe 13 is adapted to direct a maximum amount of water 20. In particular, the circumference of the water pipes 13, 19 is so large that a maximum amount of sea water can flow through the pipes 13, 19 when the pump 4 pumps sea water through the pipes 13, 19 at maximum capacity. This means that the rotor 8 can also rotate at high wind speeds, also at speeds at which the conventional turbines would be turned off. In this embodiment the installed water pipe system 5 is used at high wind speeds, while at the same wind speeds the cables and / or generator of conventional wind turbines would not be put into operation because the maximum capacity would then be exceeded. The water supply system 5 is therefore not only cheaper, 7, but also has a higher efficiency than conventional generators and / or electricity cables in conventional wind turbines.

In one embodiment the invention is applied in an ofishore wind farm. Several, for example dozens or more than one hundred, windmills 2 are provided. Each windmill 2 can be provided with a pump 4 for pumping sea water. Preferably, seawater is pumped straight from the sea in an open circuit. The pumps 4 drive the seawater jointly, for example, through the water supply system 5, for example through a submarine water line 19, with which for example one generator 6 is driven. Connecting several pumps 4 to one generator 6 has the advantage, among other things, that only one generator 6 needs to be maintained. The generator 6 thereby serves as a hydroelectric power station. This embodiment has, inter alia, the advantage that relatively large quantities of expensive and / or maintenance-sensitive generators 6 can be prevented.

The pump 4 in the windmill 2 transmits the rotation energy in the form of pressure and / or speed increase of the seawater in the water supply system 5. In one embodiment, the pump 4 becomes, for example, relatively below the mast 14, or, for example, approximately at the height of the sea surface 16 on the mast 14. In this way, no pump 4 needs to be arranged in the head 5 of the mill 2. For example, a shaft is provided here which transfers the rotation of the rotor 8 downwards in the vertical direction to the pump 4. An advantage of this embodiment is, inter alia, that no pump 4 in the head 5 needs to be arranged. Maintenance or replacement of the pump 4 can also be easily supplied.

In another embodiment, for example as shown in figure 1, the pump 4 is arranged in the head 5 of the windmill 2. This has, inter alia, the advantage that the drive shaft 11 of the pump 4 can extend in line with the rotor shaft 9, so that the rotation of the rotor 8 can be transferred relatively efficiently for driving the pump 4. The sea water is then passed along the mast 14 is pumped upwards by the pump 4, for which only a relatively inexpensive water pipe 13 has to be installed. In yet another embodiment a windmill 2 is provided with a plurality of pumps 2, for instance arranged in or near the head 5, and / or in or near the mast 14 of the windmill 2.

Compared with conventional offshore windmills 2, the arrangement of the pump 4, or in the head 5, or in or on the mast 14, has the advantage, among other things, that the top mass of the windmill 2 can remain limited, since a water pump 4 relatively light can be output with respect to a generator for a conventional wind turbine. A relatively light top mass can benefit the dynamics of the windmill 2. Through the lighter pump 4, the windmill 2 can also be constructed lighter, and / or simpler and / or cheaper. Moreover, a pump 15, in particular a mechanical water pump 4, is in many cases less maintenance-sensitive than a generator 6. The use of copper in the mill 2 can also be prevented, so that the costs can remain limited. By using a water pump 4 in or near the windmill 2 by not using a conventional wind turbine generator, the number of components in the windmill 2 can remain limited, which can reduce the chance of failure in the windmill 2 and increase the availability of the windmill 2.

In one embodiment, the system 1, in particular the pump 4, the water supply system 4 and / or the generator 6, is adapted for the use of seawater. Use is preferably made of corrosion-resistant material, in particular corrosion-resistant couplings and / or provisions to prevent growth of sea crops or the like on parts of the system 1.

The system 1 according to the invention can preferably be used at sea, but is in principle also suitable for use in 9 other waters, such as for example lakes, rivers and the like. In principle, fresh water or another liquid can be used instead of sea water.

Because the wind farms with systems 1 according to the invention can be constructed relatively inexpensively, they can for instance be equipped with relatively many wind turbines 2. For example, these systems comprise 1 power plants that are at least 200 MW (Megawatt) in size, in particular at least 500 MW. In yet another embodiment, for example, existing wind turbines 2 are adapted to be used in a system 1 according to the invention.

The described and many comparable variations, as well as combinations thereof, are considered to fall within the scope of the invention as outlined by the claims. Of course, different aspects of different embodiments and / or combinations thereof can be combined and exchanged with each other. Thus, it is not to be limited solely to the embodiments mentioned

Claims (15)

An energy extraction system, provided with an offshore windmill placed at sea, comprises a rotor; a water pump coupled to the rotor to be driven thereby for pumping sea water; a water pipe system coupled to the water pump for passing the pumped sea water; and a generator that is coupled to said water supply system, and which is non-directional to be driven by the pumped seawater to generate electrical energy. 2. System as claimed in claim 1, wherein the water supply system is provided with a basin for storing the pumped seawater, the basin being coupled to the generator, so that the stored seawater can be used to drive the generator. 3. System as claimed in claim 1 or 2, wherein the water supply system is adapted to direct the pumped seawater directly along the generator to drive it. 4. System as claimed in any of the foregoing claims, wherein the water supply system is provided with a control adapted to dose the pressure and / or speed of the seawater that drives the generator. System as claimed in claim 4, wherein the control is adapted to guide a certain amount of pumped seawater to the basin with a relatively large amount of pumped seawater, and to guide a specific amount of pumped seawater from the basin to the generator at a relatively low amount of pumped seawater . A system according to any one of claims 2 to 5, wherein an offshore platform is provided, which platform is provided with said generator and said basin. 7. System as claimed in any of the foregoing claims, wherein the water pump is located in the head of the windmill, near the rotor, 8. System as claimed in claim 7, wherein a rotor of the windmill is intended for a rotation axis that is approximately horizontal, and wherein a drive shaft of the pump is located. extends approximately in line with the axis of rotation. 9. System as claimed in any of the foregoing claims, provided with several windmills, wherein the pumps are adapted to jointly drive one generator. 10. System as claimed in any of the foregoing claims, wherein the water pipe is foreshadowing at least one water pipe whose circumference is large enough to allow seawater pumped at maximum capacity to pass through. 11. A kit for a system according to any one of the preceding claims, provided with a windmill, comprises a rotor; a water pump adapted to be coupled to the rotor to be driven thereby for pumping sea water, at least one water pipe system for passing the pumped sea water; and 20. a generator adapted to be coupled to said water supply system, and to be driven by the pumped seawater to generate electrical energy. 12. Use of seawater in a windmill, the windmill. Including a rotor, a water pump driven by that rotor for pumping the seawater for driving a generator, and a water supply system for guiding the seawater, 13. Method for generating energy, wherein a windmill rotor is driven by wind at a sea, the rotor drives a water pump, wherein the water pump pumps said seawater from the sea through a water system through said drive, which pumps the pumped seawater to a generator, the generator being driven by said seawater to generate electrical energy. A method according to claim 13, wherein the electrical energy generated is conducted to land. Method according to claim 13 or 14, wherein a number of water pumps are driven by means of a wind farm at sea for driving one generator with seawater.