Field of the Invention

The invention relates to turbine houses, and to associated dam structures, tidal energy systems, and methods.

Background to the Invention

Tidal energy systems offer the potential to generate electricity while avoiding disadvantages associated with using fossil fuels in generation. It is desirable to increase the efficiency of tidal energy systems by maximising the amount of water that flows through the turbines, and to avoid periods of time during which no electricity is being generated. Additionally, as tidal energy systems are often located in a coastal environment, it is desirable to avoid damage to components (for example, due to corrosion) and to make it easier for maintenance of components to be carried out.

Example embodiments aim to address issues associated with the prior art, whether identified herein or otherwise. Summary of the Invention

In one example, there is provided a turbine house for a tidal energy system, the turbine house comprising a plurality of turbine assemblies that include a turbine and generator in combination, characterised in that the turbine house and turbine assemblies are arranged with one another such that the turbine assemblies are removable from the turbine house as a single unit.

In one example, the turbine assemblies are arranged with one another to be removable from the turbine house as a single unit on a carrier assembly. In one example, the turbine house comprises a body to receive the carrier assembly.

In one example the turbine assemblies are completely removable from the turbine house as a single unit. In one example, the carrier assembly comprises load-bearing lifting points to enable it to be lifted from the turbine house from above

In one example, the turbine house comprises integrated lifting equipment operable to lift the carrier assembly. In one example, the carrier assembly comprises integrated lifting equipment operable to lift the carrier assembly. In one example the integrated lifting equipment comprises one or more hydraulic rams.

In one example, the turbine house comprises a locking arrangement for the carrier assembly. In one example, the locking arrangement is provided at the interface between the body of the turbine house and the carrier assembly to hold them in position relative to one another.

In one example, the turbine house comprises sealing elements to prevent water leakage at the interface of the carrier assembly and the body of the turbine house. In one example, the sealing elements and/or and locking arrangement comprise movable mechanical connectors to interface between the carrier assembly and the body of the turbine house. In one example, the movable mechanical connectors are hydraulically actuated. In one example, the movable mechanical connectors may be powered by an associated lifting system for the carrier assembly.

In one example, the turbine house comprises a first turbine assembly that comprises a first turbine having a first turbine axis which extends in an upward direction in use. In one example, the first turbine comprises a substantially vertical first turbine axis. In one example, the first turbine assembly comprises a first generator located above the first turbine in the first turbine assembly.

In one example, the turbine house comprises a second turbine assembly that comprises a second turbine having a second turbine axis which extends in an upward direction in use. In one example, the second turbine comprises a substantially vertical second turbine axis. In one example, the second turbine assembly comprises a second generator located above the first turbine in the first turbine assembly.

In one example, the first and second turbine assemblies are aligned with one another, with the second turbine assembly above the first turbine assembly. In one example, the first and second turbine axes are parallel with one another, such as aligned with one another.

In one example, the turbine house includes a first turbine assembly that comprises a first landward inlet on the landward side of the dam and a first seaward outlet on the seaward side of the dam, the first generator operable to draw power from the first turbine when water flows through the first turbine from the first landward inlet to the first seaward outlet.

In one example, the turbine house includes a second turbine assembly that comprises a second landward inlet on the landward side of the dam and a second seaward outlet on the seaward side of the dam, the second generator operable to draw power from the second turbine when water flows through the second turbine from the second landward inlet to the second seaward outlet.

In one example, the turbine house comprises a third turbine assembly. In one example, the turbine house comprises a fourth turbine assembly. In one example, the third turbine assembly comprises features corresponding to those of the first turbine assembly. In one example, the fourth turbine assembly comprises features corresponding do those of the first turbine assembly. In one example, the third turbine assembly is related to the second turbine assembly in the same manner as the second turbine assembly is related to the first turbine assembly, and/or the same for the fourth turbine assembly with respect to the third turbine assembly.

In one example, the turbine house further comprises a plurality of sluice gates for selectively closing the inlets and outlets of the first and/or second and/or third and/or fourth turbines.

In one example, there is provided a dam structure for a tidal power system, the dam structure comprising: a dam operable to prevent flow of water between a seaward side of the dam and a landward side of the dam; a turbine assembly located in the dam, the turbine assembly comprising a turbine house as described herein.

In one example, there is provided a tidal energy system comprising: a first storage basin; a second storage basin located landward of the first storage basin; and a dam structure as described herein, located between the first storage basin and the second storage basin, wherein the first storage basin is operable to: receive and store incoming tidal water; and to deliver water to the second storage basin through the turbine assembly so that power is generated by the generator assembly.

In one example, there is provided a method for servicing a turbine assembly of a turbine house for a dam structure or a tidal energy system, the method comprising: removing a plurality of turbine assemblies from the turbine house as a single unit.

In one example, the turbine house comprises that as described herein. In one example the method comprises lifting a carrier assembly out of the turbine house. In one example the method comprises completely removing the turbine assemblies from the turbine house. According to the present invention there are provided an apparatus and method as set forth in the appended independent claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

Brief Introduction to the Drawings

Figure 1 shows a schematic plan view of a tidal energy system according to an example embodiment;

Figure 2 shows a schematic side sectional view of part of the tidal energy system of Figure 1 , the section being along the centreline; and

Figure 3 shows a sectional perspective view of a turbine house according to an example embodiment.

Description of Example Embodiments

Figure 1 shows a schematic plan view of a tidal energy system 1 according to an example embodiment of the present invention. The tidal energy system 1 is for generating electrical energy from the tidal movement of sea water. Water is allowed to flow from the sea S into storage basins 10, 20, 30, B, which are also referred to as lagoons, as the tide rises, and allowed to flow from the tidal energy system 1 once the tide has gone out. Movement of water into and out of some of the storage basins 10, 20, 30, B is used to drive turbines that are coupled to electrical generators, as described in detail further below.

The tidal energy system 1 comprises a first storage basin 10, a second storage basin 20, and a third storage basin 30. The second storage basin 20 is located landward (i.e. further from the sea) than the first storage basin 10. The third storage basin 30 is located landward (i.e. further from the sea) than the second storage basin. The second storage basin 20 is located between the first storage basin 10 and the third storage basin 30. The boundaries between the sea S and the first storage basin 10, between the first storage basin 10 and the second storage basin 20 and between the second storage basin 20 and the third storage basin 30 are provided by first, second and third dam structures 11 , 12, 13 respectively.

Figure. 2 shows a schematic side sectional view of part of the tidal energy system 1 , the section being along the centreline.

During an incoming tide the first storage basin 10 receives and stores incoming tidal water 10. Water from the first storage basin 10 may be delivered to the second storage basin 20, and likewise the first storage basin 10 may receive and store outgoing tidal water from the second storage basin 20 during operation of the tidal energy system 1. In addition, the first storage basin 10 may deliver water therefrom and out of the tidal energy system 1 to sea S during an outgoing tide.

The third storage basin 30 is in use operable to receive and store water from the second storage basin 20, and to deliver water to the second storage basin 20 during operation of the tidal energy system 1 .

The second storage basin 20 is, as already indicated, operable to receive and store water from the first storage basin 10, to deliver water therefrom to the third storage basin 30, to receive and store water from the third storage basin 30, and to deliver water therefrom into the first storage basin 10 during operation of the tidal energy system 1 .

Turbines are provided in turbine houses located between the first storage basin 10 and the second storage basin 20. Furthermore, turbines are provided in turbine houses located between the second storage basin 20 and the third storage basin 30. The turbines are arranged such that movement of water from one storage basin 10, 20, 30 to the next drives the turbines between the respective storage basins 10, 20, 30. By regulating movement of water within the system, the turbines that sit at the boundaries of the second storage basin 20 can used to generate electricity during both incoming and outgoing tides, increasing the flexibility to match the output of the tidal energy system 1 to demand.

It will be appreciated that in order for the system to drain completely under gravity, the seaward storage basin may be provided with an outflow that is lower than that of the intermediate storage basin, and in turn the intermediate storage basin may be provided with an outflow that is lower than that of the landward storage basin, However, this need not necessarily be achieved by a general downward slope from landward to seaward, as there may be drainage flues, pumps, or cambered or other surface features provided at the bottom of the storage basins. Furthermore, although a generally linear arrangement from seaward to landward is preferred in order that the bulk flows water may move in the system may take place also in a generally linear manner, it is to be understood that other geometries may be used, and "seaward" and "landward" ought to be interpreted herein in relation to their functions in receiving and delivering water. Similar considerations apply to the reserve storage basins, B described in more detail below.

Figure 3 shows a sectional perspective view of a turbine house 100 which is used for the dam structures 11 , 12, 13 for the tidal energy system 1 . The turbine house 100 is operable to prevent flow of water between a seaward side 104 and the landward side 106 by controlling flow of water using sluice gates for its inlets and outlets, as described in more detail below.

The turbine house 100 comprises a first turbine 110a, a second turbine 110b, a third turbine 110c and a fourth turbine 110d. The second turbine 110b is located above the first turbine 110a. The third turbine 110c is located above the second turbine 110b. The fourth turbine 110d is located above the third turbine 110c. As such, the four turbines 110a-d provide a series of turbines at a range of heights, with the inlets and outlets of the turbines 110a-d also located at a range of heights.

The first turbine 110a comprises a substantially vertical first turbine axis. The second turbine 110b comprises a substantially vertical second turbine axis. The third turbine 110c comprises a substantially vertical third turbine axis. The fourth turbine 110d comprises a substantially vertical fourth turbine axis. Each of the turbine axes extends upwardly in use, and are used to drive a closely-coupled or integrated generator. That is, the turbines 110a- 110d are provided as turbine assemblies that include a turbine and generator in combination. The turbine axes are aligned with each other in a horizontal direction, which is landward horizontal direction.

The first turbine 110a comprises a first seaward inlet 114a on the seaward side 104, and a first landward outlet 116a on the landward side 106. The first turbine 110a further comprises a first landward inlet 118a on the landward side 106, and a first seaward outlet 120a on the seaward side 104. The first seaward inlet 114a is in fluid communication with the first landward inlet 118a. The first landward outlet 116a is in communication with the first seaward outlet 120a.

The second turbine 110b comprises a second seaward inlet on the seaward side 104, and a second landward outlet on the landward side 106. The second turbine comprises a second landward inlet on the landward side 106, and a second seaward outlet on the seaward side 104. The second seaward inlet is in fluid communication with the second landward inlet. The second landward outlet is in communication with the second seaward outlet. The inlets and outlets of the second turbine 110b correspond to those of the first turbine 110a, but raised there-above. That is, the second seaward inlet is located above the first seaward inlet. The second landward outlet is located above the first landward outlet. The second landward inlet 118b is located above the first landward inlet. The second seaward outlet is located above the first seaward outlet. The second seaward outlet is adjacent to the first seaward inlet. The second landward outlet is adjacent to the first landward inlet. Similarly, the third and fourth turbines 110c, 110d each comprise respective seaward inlets, landward outlets, landward inlets and seaward outlets. As shown in Figure 3, the respective inlets and outlets of the third turbine 110c are located above the respective inlets and outlets of the first and second turbines 110a, 110b. The respective inlets and outlets of the fourth turbine 110d are located above the respective inlets and outlets of the first, second and third turbines 110a, 110b, 110c.

The turbine house 100 further comprises an underwater turbine 121. The underwater turbine 121 comprises a substantially horizontal turbine axis. The underwater turbine 121 is located below a minimum water level, such that it is always under water during the tide cycle. The underwater turbine 121 comprises a seaward opening 123 and a landward opening 125. The underwater turbine 121 is a unit which includes turbine blades and a generator in a single unit. The turbine unit 121 can generate electrical power from flow directions landward to seaward, and also seaward to landward, through a rotating nacelle operated hydraulically, making the unit bi-directional.

The inlets and outlets for the first through fourth turbines 110a-110d, and the underwater turbine 121 are provided with sluice gates which can be used to control the flow of water through the turbine house 100, and thus control the energy output of the tidal energy system 1 . Other embodiments include staggered modules, and pods where the larger horizontal turbines 121 are not incorporated (where not required).

The turbine house 100 shown in Figure 3 comprises four sets of first through fourth turbines 110a-110d , and the underwater turbine 121 , with each set provided as part of modular arrangement so as to be readily scalable. The openings on the seaward side of the second through fourth modules are visible in Figure 3, unlabelled for the sake of clarity.

In the turbine house 100 for a tidal energy system, turbine assemblies are arranged with one another to be removable from the turbine house 100 as a single unit. It will be understood that the removable of the turbine assemblies need not result in total separation of the turbine assemblies from the turbine house. Rather, removal to allow access to the turbine assemblies, whether total removal/separation or partial is contemplated. All sluice gates are closed during removal of the turbine modules to stop any water ingress, whilst the assemblies are disconnected and removed.

In Figure 3, the demarked region adjacent to the turbines 110a-110d, 121 comprises a carrier assembly 200 for the turbine assemblies. The carrier assembly 200 is arranged to be lifted from the turbine house from above, bringing with it the turbines and associated generators. In other embodiments integrated lifting equipment may be provided in the turbine house 100, such as hydraulic rams located below the turbines.

In addition to the action of gravity holding down the carrier assembly 200, the turbine house 100 suitably comprises a locking arrangement for the carrier assembly 200 to interface between the body of the turbine house 100 and the carrier assembly 200 to hold them in position relative to one another. Sealing elements to prevent water leakage at the interface of the carrier assembly 200 and the body of the turbine house 100 are also provided. In the example embodiment of Figure 3, the sealing elements and locking arrangement comprise movable mechanical connectors (not shown). The movable mechanical connectors are hydraulically actuated, and may be powered by an associated lifting system for the carrier assembly.

By providing a modular arrangement for the turbine house, with a movable carrier assembly that can be used to enable access to the turbines and associated generators by at least partial removal from the turbine house, maintenance and/or replacement of the turbines and/or generators is facilitated. Assemblies can be simply replaced with an exchange unit and transported off-site for maintenance and or refurbishment. Modular construction and assembly will allow mass production off-site at reduced capital cost.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.