WO2009068712A1

WO2009068712A1 - Marine electric power production system and installation method

Info

Publication number: WO2009068712A1
Application number: PCT/ES2008/000740
Authority: WO
Inventors: Carlos Itoiz Beunza
Original assignee: Acciona Energia, S.A.
Priority date: 2007-11-29
Filing date: 2008-11-27
Publication date: 2009-06-04
Also published as: ES2301445A1; ES2301445B1

Abstract

The invention relates to a marine electric power production system based on a spar buoy-type floating structure which maintains the centre of gravity below the centre of buoyancy. The invention comprises a spar-type floating structure (1) incorporating: a device (2) for producing electric power from wind, and/or a device (3) for producing electric power from waves, and/or a device (12) for producing electric power from sea currents. The invention also relates to the associated installation method in which the system, having been fully constructed at a port, is subsequently floated to the desired location and finally secured to the seabed using anchoring means (11).

Description

MARINE ELECTRICAL ENERGY PRODUCTION SYSTEM AND INSTALLATION METHOD - OBJECT OF THE INVENTION.

The following invention, as expressed in the statement of the present specification, refers to a marine system of electric power production and installation method, the system being based on a floating structure type "spar" buoy, so that the own floating structure integrates, at least, an energy producing device, being able to be a wind harnessing device, such as a wind turbine and / or a device for harnessing wave energy and / or a harnessing device for Ia energy from sea currents, with the objective of obtaining electrical energy through wind and / or waves. Likewise, this method presents a method for the installation of the system that allows its uninstallation, repair and subsequent new installation.

SCOPE.

This report describes a marine system for the production of electrical energy and installation method, which is of special application for installation at sea, taking advantage of the energy provided by wind and / or waves, being integrated into a single structure floating type "spar" buoy.

BACKGROUND OF THE INVENTION Floating systems are known that incorporate a wind turbine in its upper part, as well as systems of energy use of the waves.

Also, in relation to the combination of these technologies there is a patent (JP2002303454) that describes a large floating structure in which many systems are integrated, in order to produce hydrogen and oxygen, through various technologies, including wind and wave energy .

On the other hand, the floating spa "spar" system refers to systems that maintain the center of gravity below the center of flotation, thus achieving the desired stability. The basic parts of a "spar" system include:

1) A superior structure.

2) A top ballast tank ("hard tank").

3) An intermediate section (blind or lattice cylindrical configuration).

4) A lower ballast tank ("soft tank").

The upper structure usually consists of a multi-level configuration of roofs in order to achieve a sufficient work area, while minimizing cantilever surfaces.

The upper ballast tank is responsible for providing sufficient buoyancy reserve to support the weight of the other elements, since none of them would have positive buoyancy by itself. The term "hard tank" comes from the fact that its compartments are sized to withstand all the hydrostatic pressure without flooding them. It is usually divided into 5 or 6 levels of watertight compartments separated by roofs and each of these is further subdivided into another 4 by radial bulkheads. The tank located at the height of the flotation usually has a double hull or double bulkheads ("cofferdams") to minimize the flood volume in case of collision with another vessel. In any case, it is usual that only the lowest level of tanks is flooded with a variable amount of ballast depending on the loading condition of the platform, leaving the rest empty.

The intermediate section extends from the lower base of the "hard tank" to provide the design draft to the structure. In the classic "spar" this was only an extension of the sheet that constitutes the outer lining of the upper tank with hardly any internal structure. The ladders of this central body are sized from the bending moments to resist during the phase of adrizamiento after the trailer to the point of final location. In a subsequent evolution, this central body was replaced by a less heavy lattice structure and a simpler and cheaper construction. There are other concepts of floating systems, other than "spar", such as, for example, the TLP (Leg Platform Tension) and the semi-submersible.

The TLP (Leg Platform Tension) is vertically attached, by means of tensions attached to the sea floor, in this way it avoids the ascending movement ("heave") and the rotations of the axes contained in the plane of the marine surface ("piten and roll" )

The semi-submersible is a floating structure with a large roof, from which several columns that connect underwater with horizontal floating elements (called pontoons) come out.

DESCRIPTION OF THE INVENTION

In this report, a marine electric power production system is described, being based on a floating structure type "spar" that keeps the center of gravity below the center of flotation, so that the marine electric power production system It includes a floating structure type "spar" in which it is integrated:

• a device for producing electricity through the wind, and / or; • a device for producing electricity through waves, and / or;

• a device for producing electrical energy through sea currents.

Thus, the proposed system has the advantage that the different electrical energy production devices, independently or combined with each other, are integrated into a single floating structure type "spar", while presenting a great simplicity. When integrated into a single floating structure type "spar", synergies are obtained, both in the construction and in the use of the different components of the devices integrated in it.

The device for producing electricity through wind is defined by a wind turbine.

The device for producing electricity through waves is defined by vertical generators, which can be linear electric generators, air compression devices that have a coupled electric generator or seawater or fluid compression devices that have a generator coupled to a turbine as the final device. The vertical generators are mounted between two platforms, being able to be linear electric generators or compressors of air, sea water, or other fluid, at the water level, constituted by cylindrical elements and their corresponding float movable along it by the wave action, generating electricity if it is an electric generator or compressing the corresponding fluid if it is a compressor.

The upper mounting platform of the vertical generators is at a height such that the water level does not reach the waves. The system incorporates a power electronics

(controllers) necessary for the adaptation of the generated electrical signals, according to the final application of the generated energy.

Likewise, the device for producing electrical energy through the marine currents is defined by at least one arm integral to the floating structure below the water level, provided with a rotating propeller.

The system can incorporate, at least, a controller that adapts and integrates the signals of the different generators of the system, in a single signal. Likewise, the system can incorporate, in proximity to the floating structure, a fish farm next to the wave's own energy exploitation device, allowing it to give added value to the installation, both economic and ecological.

Likewise, the system is capable of incorporating a hydrogen production device by means of water electrolysis, so that with the electric power produced, and by means of the electronics of adequate power and an electrolysing device, pure hydrogen will be obtained for various uses.

The pure water that the electrolyzer needs to produce hydrogen can be obtained by incorporating a Seawater desalination device, also integrated in the system itself.

In order to generate electricity for self-consumption, the system can incorporate photovoltaic panels, allowing it to be autonomous.

This method also describes an installation method, which also allows and facilitates system maintenance.

Thus, the installation method is based on the construction of the complete port system, the subsequent floating drag of the assembly to the chosen site and the final fastening to the seabed, by means of chains or other anchorage devices.

In addition, the proposed installation method facilitates maintenance and is based on the idea that, in case of serious breakdown, the anchoring devices are released, the system is dragged to the port and the repair work is carried out, then it is taken again to the location and is reattached with the anchoring system.

The anchoring device that incorporates the system can be of different types, and, thus, it can be: catenary lines, "taut moorings", "tension / torsion leg" or other type of anchoring device.

Likewise, the system may not be fixed to the seabed, but be able to maintain or vary its position by means of "DP" systems.

To complement the description that will then be made, and in order to help a better understanding of the characteristics of the invention, this descriptive report is accompanied by a set of drawings, whose figures are illustrative and not limiting , the most characteristic details of the invention are represented. BRIEF DESCRIPTION OF THE DESIGNS.

Figure 1. Shows a perspective view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates a wind turbine producing electric energy through the wind. Figure 2. Shows a perspective view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates an electric energy producing device through the waves.

Figure 3. It shows a front view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates an electric energy producing device through the marine currents.

Figure 4. Shows a perspective view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates a wind turbine producing electricity through the wind and a device producing Electric power through the waves.

Figure 5. It shows a front view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates a wind turbine producing electricity through the wind and an energy producing device Electric through the waves.

Figure 6. Shows a perspective view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates a wind turbine producing electricity through the wind and a device producing Electric power through sea currents.

Figure 7. Shows a perspective view of an installation of an energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates an electrical energy producing device through the waves and a producing device of electrical energy through marine currents.

Figure 8. It shows a perspective view of an installation of a global energy producing system, being based on a floating structure that integrates a "spar" type buoy, and incorporates a wind turbine, a device producing electricity through the waves and an electric power producing device through sea currents based on arms fitted with propellers.

Figure 9. Shows a detailed view of the outer zone of the wave energy use device based on some vertical generators

Figure 10. It shows a general scheme of the installation, being able to observe a wind turbine and a system of use of the waves, each with its corresponding power electronics. Figure 11. It shows a general scheme of the installation, being able to observe a wind turbine, a system of use of the waves and a common controller for both devices.

Figure 12. Shows a schematic detail of the linear generators with relative movement of the float element with respect to the cylindrical body by the action of the waves.

Figure 13. Shows a perspective view of the installation, in which photovoltaic panels are located in the upper part of the wind turbine.

Figure 14. It shows a perspective view of the installation, with an integrated fish farm next to the wave use system.

Figure 15. Shows a schematic detail of the process of converting seawater into hydrogen.

DESCRIPTION OF A PREFERRED EMBODIMENT. In view of the aforementioned figures and in accordance with the numbering adopted, we can observe how the marine electric power production system is based on a floating structure 1 type buoy "spar" that keeps the center of gravity below the center of flotation , whose floating structure 1 integrates, at least, an electric power production device, which may be based on a wind turbine 2 that takes advantage of the wind and / or an electric power production device 3 through the waves and / or a device 12 for producing electrical energy through sea currents. In this way, the floating structure 1 type buoy "spar" can mount that or those devices of energy production more convenient according to the existing environmental and maritime conditions at the installation site for optimum energy efficiency. Thus, the floating structure 1 type buoy "spar" can mount a only device producing electricity from those previously mentioned or any combination thereof.

On the other hand, each of the electric energy production devices that incorporate the floating structure 1 will have its corresponding power electronics (controllers). This power electronics has the mission of adapting the output signal of the device corresponding to the characteristics required by the output of the system.

Thus, by way of example, in a first practical execution of the invention, as seen in Figure 10 of the designs, each of the energy production devices 2 and 3 through the wind and waves, respectively , it has its power electronics 4 and 5, while in a second practical execution, as seen in Figure 11 of the designs, the individual power electronics for each device 2 and 3 of energy use of wind and waves It is replaced by a single controller 15 at the output thereof, which performs the same function of adapting the signal. This is extensible to any combination of energy production devices. In a preferred embodiment, the output of the system can be connected, through a transformer or directly to an electrical evacuation network, according to the voltage at which electricity is produced with this system.

Regarding the system of use of the waves, as can be seen, for example in Figures 2 and 9, it will consist of generators arranged vertically, located between an upper platform 8 and a lower platform 9.

These generators can be linear direct power generation or air compression systems with a second stage of air expansion, and generating electricity, or sea / fluid water compression systems with an electric generator coupled to a turbine in its final phase.

Figure 9 shows a detail of the vertical arrangement generators, which are constituted by a central axis 6, which extends between the two lower and upper platforms 9 and 8, respectively, and of a float 7 with less extension, which through its relative movement (up / down) generates electricity in the case of the linear generator or compresses air / liquids / fluids in the case of the compression system. The upper platform 8 must be at a certain height of the surface of the water 10 to never be impacted by the waves, due to the large load that they would have to bear in such case.

Due to this, between the upper platform 8 and the lower platform 9 there will have to be a certain distance to avoid impacts, which will be given depending on the oceanographic conditions of each site, which implies that this whole area will have a function structural, and therefore, will have to be calculated accordingly. The system will have funding means 11 for positioning, in order not to undergo significant changes in the location of the system.

As indicated in a practical embodiment, a device 12 for energy use of the currents (as can be seen in Figure 3) can be integrated such that 2 devices are arranged symmetrically placed with respect to the floating structure, and arranged under the water level 10, as well as photovoltaic panels 13 that generate electricity for the system's own consumption, as can be seen in Figure 13.

In a preferred embodiment, a fish farm 14 is installed next to the energy production system 3 by waves, which allows to add value to the installation, both economic and ecological. In addition, a hydrogen production system can be added by electrolysis, as seen in Figure 15 of the designs, so that with the electricity produced, and by means of the electronics of adequate power and an electrolyzer device, pure hydrogen is obtained for various uses Pure water, which electrolyser 16 needs to produce hydrogen, can be obtained by means of a desalination device 17 (desalination plant) of seawater integrated into the entire global system.

As a preferred embodiment, an installation method is also described, whereby the maintenance of the system in question is facilitated.

The installation method is based on the construction of the complete port system, the subsequent floating drag of the assembly to the chosen site and the final fastening to the seabed, by means of chains 11 or other means of anchorage.

Likewise, by means of the proposed method, maintenance tasks are facilitated, since, in the event of a serious breakdown, the means of anchoring are released, the system is dragged to the port and the repair work is carried out, then it is taken back to the site and it is restrained with the funding means.

There are several possibilities of anchoring device: catenary lines, "taut moorings", "tension / torsion leg" or other type of anchoring device. Each of the concepts is explained below: • Catenary lines: They are the oldest and most common funding systems. Its restoration strength is based mainly on its weight.

• "Taut moorings": These are lines with a specific claim. Its restoring force is achieved by the elastic characteristics of the material.

• "Tension / torsion leg": The flotation of the platform exceeds its weight, and this type of line counteracts the net force in a vertical and upward direction, holding the platform. These types of lines are typical of TLP platforms, although they could also be used for other platforms, and one of these lines could even be used to hold a platform.

The catenary lines can use passive devices, such as dead weights, or floats, along their lines, in order to improve the dynamics of the floating structure or behavior structural of the line.

There is also the possibility of not using anchoring devices. This implies that the system would not be fixed to the seabed, and yet it is capable of maintaining or varying its position by means of "DP" systems or other devices.

The "DP" ("Dynamic Positioning") systems are active devices to control the position of the structure. They are based on an active system, such as propellers, or any other system that allows displacement, they are also controlled by a control device.

Claims

R E I V I N D I C A C I O N E S.

1 ^a .- MARINE ELECTRICAL POWER PRODUCTION SYSTEM, being based on a floating spar "spar" that maintains the center of gravity below the center of flotation, characterized in that the marine system of electric power production comprises a floating structure (1) type "spar" in which it is integrated:

• a device (2) for producing electricity through the wind, and / or; • a device (3) for producing electrical energy through the waves, and / or;

• a device (12) for producing electrical energy through sea currents.

2 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, wherein the device (2) production of electricity by wind, is defined by a wind turbine.

3 .- MARINE SYSTEM ELECTRICITY, according to claim 1, characterized in that the device (3) production of electricity through the waves is defined by at least a linear electric generator and / or air turbine and / or a marine water turbine and / or a turbine of a particular fluid.

4 .- MARINE SYSTEM ELECTRICITY, according to claims 1 and 3, characterized in that the vertical generators (6-7) are mounted between two platforms (8- 9) and may be a linear electric generator or a air compressors, at the water level, constituted by cylindrical elements (6) and their corresponding float (7) movable along it, by the action of the waves, generating electricity if it is an electric generator or compressing air if it is about air compressors, seawater compression or other fluids.

5 .- MARINE SYSTEM ELECTRICITY according ^to claim 4, characterized in that the platform (8) mounting upper vertical generators (6-7) It is at such a height of the level (10) of the water that the waves do not reach him.

6 .- MARINE SYSTEM ELECTRICITY, according to claim 1, characterized in that the device (12) for producing electrical energy through sea currents is defined by at least one arm integral to the floating structure below the water level (10), equipped with a rotating propeller.

7 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, wherein the system includes at least a controller that adapts and integrates the signals from different generators system, into a single signal.

8 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, wherein the system includes a fish farm (14) by the floating device itself.

9 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, characterized in that the system incorporates a device (16) for producing hydrogen by electrolysis of water. 10 .- MARINO ENERGY PRODUCTION SYSTEM

POWER, according to claim 1, wherein the system includes a device (17) for desalinating seawater to obtain pure water, for certain applications, such as producing hydrogen.

11 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, characterized in that the system incorporates photovoltaic panels (13) providing electrical power for different control systems, instrumentation, data recording and transmission.

12 ^a. - METHOD OF INSTALLATION OF THE MARINE SYSTEM OF PRODUCTION OF ELECTRICAL ENERGY, according to claims 1 ^to 11 ^a , characterized in that the system is built entirely in port, then it is dragged in flotation to the chosen site, and finally , is fastened to the seabed with funding means (11). 13 ^a .- MARINE SYSTEM INSTALLATION METHOD OF PRODUCTION OF ELECTRICAL ENERGY, according to claim 12 ^a , characterized in that in the case of a serious failure, the anchoring means (11) are released, the system is floated to the port, repair work is carried out, and finally it is brought back to the site and is restrained with the anchoring means (11).

14 .- MARINE SYSTEM ELECTRICITY, according to claim 1, characterized in that the system incorporates a laying device, which can be: lines catenary "taut moorings", "tension / torsion leg" or other device of funding.

15 .- MARINE SYSTEM ELECTRICITY according ^to claim 1, characterized in that the system is not secured to the seabed, but is able to maintain or vary its position by "DP" (Dynamic Positioning) systems.