EP2700594B1 - Method for making an underwater storage device - Google Patents

Description

The invention relates to a method for producing an underwater storage, in particular for the storage of electrical energy in the form of potential energy. Instead of the term underwater storage, the term storage is also briefly used below. Underwater storage means, in particular, a storage container having a relatively large internal volume, wherein the storage or storage container is arranged at a greater depth of water of, for example, 200 m to 1500 m in a body of water. The water is, in particular, a sea, and expediently, the underwater reservoir stands or lies on the seabed.

The publication WO 98/13556 discloses a method of manufacturing an underwater storage.

Such underwater storage are already known in principle for energy storage. They work in a similar way to a pumped storage power plant that takes advantage of the gradient between a lower water reservoir and an upper water reservoir. In particular, electrical energy from offshore wind power plants and / or from solar plants in the form of potential energy is to be stored or temporarily stored with such an underwater storage. The underwater storage is initially at least partially filled with water or sea water. With the help of, for example, obtained in wind turbines electrical energy then arranged in the underwater storage pump is operated, with which the water contained in the memory is pumped to the outside. If necessary, then let the water flow back into the memory and due to the upcoming significant pressure gradient can be generated in turn with the help of arranged in the underwater storage turbine and generators electrical energy in a simple manner. Cable connections allow the transport of electrical energy. Thus, again and again between storage and Generation of electrical energy to be changed. - So far, however, no satisfactory concepts for the production of particularly large-volume submersible storage are known. The hitherto known proposals are characterized by an undesirably considerable expense or expense.

In contrast, the invention, the technical problem of providing a method of the type mentioned above, with the simple and inexpensive and less expensive way an underwater storage can be made.

To solve this technical problem, the invention teaches a method for producing an underwater storage or a spherical underwater storage, in particular for the storage of electrical energy in the form of potential energy, the underwater storage is preferably made floating in a body of water in the region of the water surface, wherein first an outer base formwork is provided in the lower region of the memory to be formed, wherein an inner formwork is produced by - starting in the lower part of the memory - inner torus rings are successively superimposed, so that a spherical inner formwork results, wherein on the outer base formwork a outer formwork is produced by successively stacking outer toroidal rings, the inner formwork being spaced from the outer base formwork and spaced from the outer formwork, and the space between Inn Formwork and outer formwork as well as between inner formwork and outer formwork is filled with concrete.

The underwater storage according to the invention is floating according to the invention in a body of water in the water surface produced. The water is in particular a sea, and preferably the underwater reservoir is placed on the sea floor after its completion. The preparation of the underwater storage can also be done in a protected water such as in the area of a port and the like. It is also within the scope of the invention that the underwater storage according to the invention is produced in a dry dock without water or virtually without water and that the underwater storage produced in this way is subsequently transported to its site and is conveniently lowered to the seabed. - Spherical does not necessarily mean an exact spherical shape within the scope of the invention. There may be deviations from the exact spherical shape. In that regard, spherical means in particular also substantially spherical. Conveniently, at least the interior or the inner storage space of the underwater storage according to the invention is spherical.

It is within the scope of the invention that the underwater storage is equipped with at least one pump for pumping out water from the interior of the underwater storage. It is also within the scope of the invention that the underwater storage according to the invention has at least one turbine and at least one generator for the generation of electric current when water flows into the underwater storage. Instead of a separate pump and a separate turbine, a combined pump turbine can also be used. The underwater storage according to the invention works in a similar way to a pumped storage power plant. In that regard, reference may be made to the introductory notes.

Torus ring in the context of the invention means a ring body and in particular a circular ring body or substantially circular ring body. Conveniently, a cross section through the ring is circular or substantially circular.

According to a preferred embodiment of the method according to the invention, a support device, in particular a support ring on a plurality of floats floating on the water surface or pontoons is stored, wherein the outer base formwork is suspended from the support ring is / and wherein the outer base formwork is lowered, so that they at least partially immersed in the water or in the water surface. Conveniently, the support ring is an annular lattice girder.

Empfohlenermaßen an outer base formwork is used in the method according to the invention, which has a formwork network, in particular a wire rope net and an internally applied to the network base formwork membrane. The inside refers to the later interior of the memory facing side or surface of the network. The mesh size of the formwork network or wire rope network may for example be 50 x 50 cm. The basic formwork membrane can be attached to the formwork network before the installation of the formwork network or even after the installation of the formwork network, but then at least partially under water.

According to a preferred embodiment, an outer base formwork is used, which has a bottom formwork floor - for example in the form of lattice girders lying on formwork elements -, wherein on the formwork floor a central support pole is mounted and wherein the support mast is used as a base or as a support element for the inner formwork. Preferably, the shuttering floor is circular.

Conveniently, torus rings are set on top of each other to produce the inner formwork and further applied an inner formwork membrane on the outside of the superimposed inner torus rings. This inner formwork membrane can be composed of individual membrane pieces or membrane strips which are fastened successively on the outside of the inner torus rings. In principle, however, it may also be a coherent inner formwork membrane, which is applied to the outside of the torus rings or is stretched over the torus rings. According to one embodiment variant, this inner shell membrane having the shape of an inner ball can also be inflated from the inside. Conveniently, the inner toroidal rings are temporarily attached to the inner formwork membrane, for example by means of loop straps or the like. This makes an easy replacement of the inner torus rings possible. The inner torus rings can also be interconnected in a corresponding manner.

It is within the scope of the invention that, to produce the outer formwork, an outer formwork membrane is furthermore applied on the inside of the stacked outer toroidal rings. The outer formwork membrane and the base formwork membrane of the outer base formwork described above may be one and the same formwork membrane. The base formwork membrane can then extend beyond the outer base formwork upwards for the purpose of producing the outer formwork. According to a particularly preferred embodiment of the invention, the outer base formwork and the outer formwork arranged above are produced or combined with the proviso that they complement each other to form a spherical outer formwork. The outer base formwork and the outer formwork arranged above it thus form the outer formwork or the spherical outer formwork.

It is recommended that gas-filled or air-filled torus rings be used for the inner torus rings and / or outer toroidal rings. These are preferably compressed air-filled torus rings. The torus rings then have due to their compressed air filling own stability, which is sufficient to absorb the substantially horizontally acting shuttering pressure.

The base formwork membrane and / or the outer formwork membrane and / or the inner formwork membrane and / or the wall of the inner torus rings and / or the wall of the outer torus rings expediently consists of a fiber-reinforced plastic and in particular of a fiber-reinforced synthetic rubber. The fiber-reinforced synthetic rubber is preferably a fiber-reinforced chloroprene rubber. Aramid fibers are expediently used for fiber reinforcement of the fiber-reinforced plastic. The aramid fibers can be present in the form of a fiber fabric.

The advantages of formwork with gas-filled or compressed air-filled torus rings are explained below. The torus rings with the associated formwork membrane correspond as it were to a pneumatically supported formwork. This pneumatically supported formwork can in particular by means of compressed air without great effort and within a relatively short period of time and be dismantled again. It is within the scope of the invention that the spherical underwater storage in its upper region or in the region of its upper vertex has an opening, in particular a circular opening with a diameter of for example about 3 m. Such an opening or circular opening, for example, by the installation of a steel ring in the form of a built-in with anchoring in the Concrete shell of the underwater tank can be realized. It is also within the scope of the invention that the pneumatically supported formwork is basically reusable or designed for multiple use. So the pneumatically supported inner formwork can be taken from the interior of the store after concreting and after hardening of the concrete of the spherical underwater storage. For this purpose, the air or compressed air is expediently let out of the torus rings and then the torus rings can be removed individually or in larger segments - possibly also complete with the shuttering membrane - through the opening in the upper region of the underwater storage.

It is understood that the torus rings for use as pneumatically supported formwork must have sufficient stability. For this purpose, the ring diameter and the diameter of the torus (diameter of the cross section through the torus ring itself) are expediently adapted correspondingly to one another. It is further recommended that the toroidal rings have an inner gas pressure or air pressure adapted to the ring diameter and the torus diameter. A sufficient dimensional stability and positional stability of the torus rings can be achieved without additional support, in particular, according to the preferred embodiment, the concreting of the hollow sphere with limited concreting heights in layers, so that the lateral pressure on the horizontally arranged torus rings is circumferentially even as possible and remains ,

A recommended embodiment of the method according to the invention is characterized in that in the interior of the memory a Rüstturm or a central Rüstturm is built and that this Rüstturm is supported by stiffening elements on the inner formwork. The Rüstturm thus serves in particular to stabilize the formwork construction. He can also be called in the interior of the store existing entrance can be used. Conveniently, the Rüstturm is mounted on the support pole described above.

According to a preferred embodiment of the method according to the invention, the concrete is successively filled into the intermediate space as a function of the progress made in the construction of the inner formwork and / or the outer formwork. It is therefore within the scope of the invention that the concrete is gradually filled into the intermediate space during the production of the formwork or formwork. In this case, a continuous filling of the gap can take place during the formwork construction. According to one embodiment of the invention, first the inner formwork is completed and then the concrete is successively filled in dependence on the progress in the construction of the outer formwork in the intermediate space. In this case, the outer formwork membrane can be applied in segments to the inside of the stacked outer torus rings. The segments of the outer formwork membrane can, for example, be unwound from a supply reel and fixed to said inner side of the outer torus rings. The connection can be realized in particular by gluing or by means of Velcro fasteners. It is within the scope of the invention that in a first concreting phase the lower area of the store or the interspace in the area of the outer base formwork is filled with concrete. The concrete then extends in particular to below the inner formwork of the inner torus rings. As a result, the inner formwork is buoyant. This buoyancy can counteract the above-explained, connected to the set tower stiffening elements.

A particularly preferred embodiment of the method according to the invention is characterized in that the concrete over a plurality of poured over the circumference of the formwork distributed concrete feeders into the space. As a result, a uniform pressure distribution is achieved on the formwork or on the inner formwork and the outer formwork. Conveniently, concrete pumps are used as concrete feeders. For example, four concrete feeders or four concrete pumps can be distributed over the circumference of the formwork. It is recommended that the concrete feeders be moved along the perimeter of the formwork over the gap. In this way, a continuous and layered filling of concrete in the gap can be realized. Conveniently, the concrete feeders are connected to a rotating production unit. This is therefore possible in a simple manner, because the formwork and the intermediate space are in particular annular or circular. Preferably, a continuous rotation of the rotating production unit takes place. The rotating production unit is preferably a gantry crane, wherein the gantry crane expediently has curved crane towers which are supported on the carrying device or on the support ring. According to a preferred embodiment, the crane towers of the gantry crane are moved during the rotation of the gantry crane on the support device or on the support ring. - It is within the scope of the invention that after curing or hardening of the concrete formwork are removed, ie, the outer base formwork and / or the outer formwork and / or the inner formwork is / are removed.

A recommended embodiment of the invention is characterized in that a fiber concrete is used as concrete. The concrete used so fibers are admixed at least one type of fiber. The fibers may in particular be at least one type of fiber from the group "steel fibers, plastic fibers, It is expedient to use a fiber concrete grade C40 / 50.

Preferably, a memory is produced with an internal storage volume of at least 8,000 m ³ , preferably of at least 10,000 m ³ . Particularly preferred is an inner storage volume of 8,000 m ³ to 15,000 m ³ , for example of about 12,000 m ³ . The thickness of the concrete shell is recommended to be 2.20 m to 3.50 m and preferably 2.40 m to 3 m.

It is within the scope of the invention that the thickness of the concrete shell of the memory in dependence on the maximum buoyancy of the underwater storage and according to the static and possibly also dynamic concerns is measured. The underwater storage device according to the invention is preferably designed so that in all operating states the output predominates due to the design weight of the storage compared to the buoyancy of the storage due to the water displacement. It is understood that the concrete shell of the memory at greater depths, for example over 750 m with increasing depth of water must withstand a relatively large external pressure. Accordingly, the thickness of the concrete shell must then be chosen larger and / or the strength of the concrete must be adjusted accordingly, for example by the choice of a high-strength concrete.

According to a particularly recommended embodiment of the invention, the finished storage or underwater storage is lowered to a water depth of at least 200 m, preferably at least 700 m. Water depth here means in particular the distance of the bottom of the memory to the water surface.

The invention is based on the finding that with the method according to the invention a relatively simple and inexpensive production of an underwater storage, in particular for the storage of electrical energy is possible. In this case, both the cost of materials and the amount of work can be kept within limits. As a result, the underwater storage can be manufactured at a relatively low cost. With the underwater storage device according to the invention, for example, an effective and functionally reliable change between power storage and power generation is possible in the long term. Thus, electrical energy, especially from renewable energy sources, especially from wind turbines can be easily stored or cached and with a relatively high efficiency.

Fig. 1

Eine Übersichtszeichnung mit einem Unterwasserspeicher in Form eines Speichers zur Energiespeicherung am Meeresboden,

Fig. 2

eine erste Phase des erfindungsgemäßen Verfahrens zur Herstellung eines kugelförmigen Unterwasserspeichers,

Fig. 3

eine Draufsicht auf die Komponenten gemäß Fig. 2,

Fig. 4

eine zweite Phase des erfindungsgemäßen Verfahrens,

Fig. 5

eine Draufsicht auf die Komponenten gemäß Fig. 4,

Fig. 6

eine dritte Phase des erfindungsgemäßen Verfahrens,

Fig. 7

eine vierte Phase des erfindungsgemäßen Verfahrens, und

Fig. 8

eine perspektivische Darstellung eines Torus-Ringes für die Innenschalung und/oder für die äußere Schalung.

The invention will be explained in more detail with reference to a drawing showing only one exemplary embodiment. In a schematic representation:

Fig. 1

An overview drawing with an underwater storage in the form of a storage for energy storage at the seabed,

Fig. 2

a first phase of the method according to the invention for producing a spherical underwater storage,

Fig. 3

a plan view of the components according to Fig. 2 .

Fig. 4

a second phase of the process according to the invention,

Fig. 5

a plan view of the components according to Fig. 4 .

Fig. 6

a third phase of the process according to the invention,

Fig. 7

a fourth phase of the process according to the invention, and

Fig. 8

a perspective view of a torus ring for the inner formwork and / or for the outer formwork.

The Fig. 1 shows a spherical underwater storage 1 according to the invention produced in the operating state. The underwater storage 1 is located at a depth of about 700 m on the seabed. Electric power generated by wind turbines 2 is supplied via a cable connection 3 to a pump 4 of the underwater storage 1. As a result, the pump 4 is driven and pumped out of the underwater storage tank 1 in the interior 5 of the underwater storage tank 1 existing water. In this way, the underwater storage 1 can be completely or partially emptied. If there is energy demand at a later time, seawater is allowed to flow via the turbine 6 back into the interior 5 of the underwater storage tank 1. By means of a generator, not shown, electrical current can thus be generated again and be dissipated via a cable connection 7. With the underwater storage 1 so electrical energy can be stored or cached in the form of potential energy.

The Fig. 2 to 8 illustrate the preparation of a spherical underwater storage 1 by the method according to the invention. In the Fig. 2 and 3 a first phase of this process is shown. Here, a support ring 8 was applied in the form of an annular lattice girder on pontoons 9 floating on the water surface. To the support ring 8, the lower outer base formwork 10 is connected. This outer base formwork 10 has a wire rope net 11 and a base formwork membrane applied on the inside 12 on. Furthermore, a underside shuttering floor 13 is connected to the wire rope net or inserted and on this formwork floor 13 centrally a support pole 14 is mounted.

The Fig. 4 and 5 show a second phase of the process according to the invention. Here, the bottom-side shuttering bottom 13 was lowered with the attached wire rope net 11 and the base shuttering membrane 12 applied thereto by flooding and / or ballasting under the water surface. The wire rope net 11 is stretched here and has assumed its final shape. On the support mast 14 with the construction of the spherical inner formwork 15 was started. For this purpose, inner torus rings 16 are set with different ring diameters on top of each other. In addition, in this second phase of the method according to the invention has already begun with the establishment of a Rüstturms 17 on the support mast 14.

In Fig. 6 a third phase of the process according to the invention is shown. Here, the structure of the inner formwork 15 with further inner torus rings 16 was continued and also the Rüstturm 17 further built. The setting tower 17 is otherwise connected via stiffening elements 18 to the inner formwork 15. In the third phase according to Fig. 6 was further begun with the construction of the outer formwork 19 by means of outer torus rings 20. Again, outer torus rings 20 are set with different ring diameter to realize a spherical shape over each other. Fig. 6 also shows that in this construction phase concrete 21 has already been filled into the space between the lower outer base formwork 10 and the inner formwork 15. In the area of the lower-level shuttering floor 13, as it were, a base 22 of the underwater storage tank 1 is formed, and with this base 22, the underwater storage tank 1 can safely stand up on the seabed.

In the Fig. 7 a fourth phase of the method according to the invention is shown. Here, the spherical inner formwork 15 was virtually completed and the structure of the outer formwork 19 was continued by placing further outer toroidal rings 20. A comparative consideration of Fig. 6 and 7 In addition, if you take the fact that the outer base formwork 10 and the outer formwork 19 complement each other to form a spherical outer formwork. Incidentally, it is not shown in the figures that, preferably and in the exemplary embodiment, an inner formwork membrane is applied to the outside of the inner formwork 15. In addition, it is expedient and in the embodiment on the inside of the outer formwork 19 with progressive structure of this outer formwork 19 segmentally applied an outer formwork membrane. - Fig. 7 shows further that, according to a preferred embodiment for the production of the underwater storage 1 with a gantry crane 23 is used. This gantry crane 23 has preferably and in the exemplary embodiment four curved crane towers 24 with which the gantry crane 23 can be moved on the support ring 8, so that the gantry crane 23 can rotate about a central axis. Empfohlenermaßen and in the exemplary embodiment Fig. 7 At each crane tower 24 a concrete feeding device in the form of a concrete pump 25 is arranged. As the structure of the outer formwork 19 progresses, concrete can be introduced into the space between the outer formwork 19 and the inner formwork 15 in layers, preferably continuously, via these concrete pumps 25. Due to the rotation of the gantry crane 23, a very effective distribution of the concrete takes place and this results in a uniform pressure distribution on the formwork. Conveniently, the introduced concrete 21 is compacted with internal vibrators or immersion vibrators, not shown. The structure is continued in this way, so that finally a spherical outer formwork and a spherical inner formwork with in the space between the formwork introduced concrete 21 results. After curing of the concrete, the formwork can be removed, leaving an in Fig. 1 shown spherical underwater storage tank 1 of concrete 21 is obtained.

In the Fig. 8 Incidentally, a torus ring 16, 20 is shown, which can be used as an inner torus ring 16 for the inner formwork 15 or as an outer torus ring 20 for the outer formwork 19. It can be seen that the torus ring 16, 20 is circular. Incidentally, a cross section through the torus ring 16, 20 is preferably also circular, with a constant cross-sectional diameter d over the circumference of the torus ring 16, 20. The torus ring 16, 20 is recommended to be a compressed air-filled torus ring 16, 20. The wall of the torus ring 16, 20 is expediently made of a fiber-reinforced plastic layer or rubber layer.

Claims (15)

1. A method for producing a spherical underwater storage unit (1), in particular for the storage of electrical energy in the form of potential energy, wherein the underwater storage unit (1) is preferably produced floating in a body of water in the region of the water surface, wherein initially an external base formwork (10) is provided in the lower region of the storage unit (1) to be formed, wherein an internal formwork (15) is created, in that internal torus rings (16) are placed above one another, so that a spherical internal formwork (15) results, wherein an external formwork (19) is created on the external base formwork (10), in that external torus rings (20) are placed above one another, wherein the internal formwork (15) is arranged with spacing from the external base formwork (10) and from the external formwork (19) and wherein the intermediate space between internal formwork (15) and external base formwork (10) and between internal formwork (15) and external formwork (19) is filled with concrete (21).
2. The method according to claim 1, wherein a support device, in particular a support ring (8) is mounted on a plurality of floats or pontoons (9) floating on the water surface, wherein the external base formwork (10) is suspended on the support device and wherein the external base formwork (10) is lowered, so that the same submerges into the water surface at least to some extent.
3. The method according to one of claims 1 or 2, wherein an external base formwork (10) is used, which has a formwork mesh, particularly a wire cable mesh (11) and a base formwork membrane (12) applied onto the mesh on the inner side.
4. The method according to one of claims 1 to 3, wherein an external base formwork (10) is used, which has an underside formwork base (13), wherein a support mast (14) is mounted on the formwork base (13) and wherein the support mast (14) is used as a base or as a support element for the internal formwork (15).
5. The method according to one of claims 1 to 4, wherein to create the internal formwork (15), an internal formwork membrane is furthermore applied on the external side of the inner torus rings (16) that have been placed above one another.
6. The method according to one of claims 1 to 5, wherein to create the external formwork (19), an external formwork membrane is furthermore applied on the inner side of the external torus rings (20) that have been placed above one another.
7. The method according to one of claims 1 to 6, wherein the external base formwork (10) and the external formwork (19) arranged thereabove are created or combined with the proviso that they complement one another to form a spherical external formwork.
8. The method according to one of claims 5 to 7, wherein gas-filled or airfilled torus rings (16, 20) are used for the internal torus rings (16) and/or for the external torus rings (20).
9. The method according to one of claims 1 to 8, wherein a central scaffolding tower (17) is erected in the interior (5) of the storage unit (1) and wherein the scaffolding tower (17) is supported via stiffening elements (18) on the internal formwork (15).
10. The method according to one of claims 1 to 9, wherein the concrete (21) is poured into the intermediate space successively depending on the progress when building the internal formwork (15) and/or the external formwork (19).
11. The method according to one of claims 1 to 10, wherein the concrete (21) is poured into the intermediate space via a plurality of concrete supply apparatuses distributed over the circumference of the formworks.
12. The method according to claim 11, wherein the concrete supply apparatuses are moved along the circumference of the formworks above the intermediate space.
13. The method according to one of claims 1 to 12, wherein a fibrereinforced concrete is used as concrete.
14. The method according to one of claims 1 to 13, wherein a storage unit with an internal storage volume of at least 8,000 m³, preferably at least 10,000 m³ is produced.
15. The method according to one of claims 1 to 14, wherein the finished storage unit (1) is lowered to a water depth of at least 200 m, preferably at least 700 m.

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