GB2497962A - Installing an underwater structure on a bed - Google Patents
Installing an underwater structure on a bed Download PDFInfo
- Publication number
- GB2497962A GB2497962A GB1122256.9A GB201122256A GB2497962A GB 2497962 A GB2497962 A GB 2497962A GB 201122256 A GB201122256 A GB 201122256A GB 2497962 A GB2497962 A GB 2497962A
- Authority
- GB
- United Kingdom
- Prior art keywords
- bed
- power
- text
- installation
- power cable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000009434 installation Methods 0.000 claims abstract description 56
- 238000000034 method Methods 0.000 claims abstract description 42
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- 238000005553 drilling Methods 0.000 description 20
- 238000011084 recovery Methods 0.000 description 4
- 238000003491 array Methods 0.000 description 2
- 239000011440 grout Substances 0.000 description 2
- 230000005611 electricity Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000009527 percussion Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D15/00—Handling building or like materials for hydraulic engineering or foundations
- E02D15/08—Sinking workpieces into water or soil inasmuch as not provided for elsewhere
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D27/00—Foundations as substructures
- E02D27/32—Foundations for special purposes
- E02D27/52—Submerged foundations, i.e. submerged in open water
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B13/00—Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus; Power stations or aggregates
- F03B13/12—Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus; Power stations or aggregates characterised by using wave or tide energy
- F03B13/26—Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus; Power stations or aggregates characterised by using wave or tide energy using tide energy
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B17/00—Other machines or engines
- F03B17/06—Other machines or engines using liquid flow with predominantly kinetic energy conversion, e.g. of swinging-flap type, "run-of-river", "ultra-low head"
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/30—Energy from the sea, e.g. using wave energy or salinity gradient
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- Mechanical Engineering (AREA)
- Combustion & Propulsion (AREA)
- Chemical & Material Sciences (AREA)
- Oceanography (AREA)
- Power Engineering (AREA)
- Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
- Earth Drilling (AREA)
Abstract
A method for installing a structure (2) on a bed (4) of a body of water (5) includes attaching an underwater power cable (12) to the structure, providing an installation rig(10) for securing the structure to the bed, and operating the installation rig using power and control signals supplied via the underwater power cable. The power cable is subsequently used for exporting electrical power from an electrical power generator (3) mounted on the structure. A second invention involves deploying an underwater structure to a bed and operating an installation unit to create a securing hole in the bed using power supplied by a power cable which is adjacent the bed.
Description
INSTALLING UNDERWATER STRUCTURES
The present invention relates to installing underwater structures and, in particular, to installing a structure on a bed of a body of water.
BACKGROUND OF THE INVENTION
It is becoming increasingly important to secure structures to sea beds and riverbeds in areas of high flow. For example, tidal flow electricity generating turbines must be installed in relatively high flow areas in order to be able to generate the desired electrical power.
Installation of underwater structures in such areas of high flow has conventionally been achieved using expensive jack-up rigs, having extendible legs which engage with the sea bed, and which carry a deployment rig clear of the water surface. An alternative technique is to us a dynamic positioning (DP) vessel which makes use of sophisticated location finding and positioning techniques, for example using the global positioning system (GPS) and multiple thrusters, to maintain the vessel within a close range of a desired position. Such techniques then make use of traditional drilling techniques for enabling the structure to be fixed to the sea bed using one or more piles.
However, jack-up rigs and DP vessels are expensive to deploy. It is, therefore, desirable to reduce dependence upon expensive deployment vessels.
UK Patents Nos. GB2431 189 and GB2448358 describe techniques in which less sophisticated, and hence less costly, vessels can be used to deploy and install underwater structures. Such techniques make use of flexible umbilical cables for supplying power and control signals to drilling rigs installed on the structure itself. The structure and drilling rigs are lowered to the bed from the vessel, and then the drilling operations take place under the control of the vessel. Such flexible umbilical cables enable the installation vessel to operate over a greater range of position compared to previous techniques.
However, the vessel must be present durng the whole of the drilling cycle, which can delay deployment of subsequent structures. This is potentially problematic when tidal stream turbines arrays are considered. Such arrays are intended to have many individual machines, each of which has a support structure, and so such "serial" installation means that the installation of the array takes a large number of vessel-days to complete.
Accordingly, it is desirable to provide a deployment and installation technique which enables the use of fewer installation vessels and/or speeds up the deployment process for each support structure.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a method for installing a structure on a bed of a body of water, the method including attaching an underwater power cable to the structure, providing an installation rig for securing the structure to the bed, and operating the installation rig using power and control signals supplied via the underwater power cable, wherein the power cable is subsequently used for exporting electrical power from an electrical power generator mounted on the structure.
According to another aspect of the present invention, there is provided a method of deploying an underwater structure to a bed of a body of water, the method comprising providing a power source on an adjacent bed of a body of water, deploying an underwater structure to the bed, the underwater structure carrying a drilling unit operable to drill a securing hole in the bed, connecting the drilling unit to the power source, operating a drilling unit to drill at least one securing hole in the bed using power supplied by the power source, and disconnecting the power source from the drilling unit, and recovering the drilling unit from the underwater structure.
According to another aspect of the present invention, there is provided a method of deploying underwater structures to the bed of a body of water, the method comprising providing the underwater structure with power transfer connections, connecting the power source to the power transfer connections, attaching a drilling unit to the structure, connecting the drilling unit to the power transfer connection such that power can be provided to the drilling unit by the power source, lowering the structure and attached drilling unit to the bed of the body of water, operating the drilling unit to drill at least one securing hole in the bed, disconnecting the drilling unit from the power transfer connections and from the structure, and retrieving the drilling unit from the structure.
In one example, the step of attaching the installation unit to the structure occurs in advance of the step of deploying the structure to the bed.
In another example, the step of attaching the installation unit to the structure occurs after the step of deploying the structure to the bed.
A method may further comprise connecting the power cable to a power connection unit located on the structure, and connecting the installation unit to the power connection unit.
In one example of such a method connecting the installation unit to the power connection unit occurs substantially simultaneously with the step of attaching the installation unit to the structure.
In another example, the structure includes a turbine receiving portion, and the step of attaching the installation unit to the structure includes engaging the installation unit with the turbine receiving portion.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates an underwater water current turbine; Figures 2 to 6 illustrates respective steps in a method embodying the present invention; Figure 7 is a flow chart showing steps in the method shown in Figure 2 to 6; Figure 8 to 13 illustrate steps in another method embodying the present invention; and Figure 14 is a flow chart showing steps in the method shown in Figures 8 to 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 illustrates a water current turbine 1 installed on a bed 4 of a body of water 5. The water current turbine 1 comprises a support structure 2 secured to the bed 4, and a turbine 3 installed on the support structure 2. Although the present invention will be described with reference to such a water current turbine, it will be appreciated that embodiments of the present invention can be applied to deployment of any underwater structure, whether that be used for power generation, or for any other purpose. For example, offshore wind turbine towers, water current turbines, tidal stream turbines, wave energy converters, or oil and gas equipment, could be secured to the sea bed using a technique embodying the present invention.
In order to deploy the current turbine 1 on the bed 4 of the body of water, the support structure 2 must first be attached to the bed 4. Figure 2 illustrates a deployment vessel 6 on the surface of the water 5 carrying the structure 2 prior to deployment of that structure 2 to the bed 4. The vessel 6 is equipped with a crane or hoist 7 for deploying the structure from the vessel 6.
Figure 3 illustrates a second step in the method embodying the present invention in which pile installation units 10, for example a drilling unit, and associated piles 11, are attached to each leg of the structure 2. A hoist cable 9 is attached to the support structure 2 from the crane 7, in preparation for lowering the structure 2 to the bed 4. As will be described in more detail below, the pile installation units 10 operate to provide holes for the piles 11 and operate to grout those piles into place in the holes, thereby securing the structure 2 to the bed 4.
An underwater power cable 12 is provided adjacent the sea bed 4, and is recovered, for example using a remotely operated vehicle (ROV) and/or a crane, grapple, winch or any suitable recovery equipment, to the vessel 6. The power cable 12 is attached to a power connection unit (not shown) located on the support structure 2. The power cable 12 provides power supply lines and control lines from a shore based or remotely operated power and control centre.
In one example, the power cable 12 is the cable that will be used to export power from the generating turbine to the shore (either directly, or via intervening equipment such as transtormers, inverters, and/or isolators) when the generating turbine is in use. In such an example, the power cable 12 is to be attached to the power connection unit on the structure 2 in any event, and so the connection step is not additional to the deployment process.
In one example, the power connection unit on the structure is provided with a length of cable to which the power cable 12 can be attached, using a connector or a splicing technique.
Such a length of cable from the power connection unit is preferably attached before the structure is loaded onto the vessel 6 -that is, the power connection unit is provided with the connection cable during manufacture of the structure.
In other examples, the power cable 12 can be attached to the power connectors at any appropriate time. For example, the power cable 12 may be attached to the power connectors of the structure 2 when the structure 2 is located on the sea bed 4. Such attachment could be achieved using divers or remotely operated vehicles (ROVs).
When the structure is provided with a length ot cable to which the power cable is to be connected, the structure may be lowered to the bed, and the powei cable 12 and the connecting cable recovered to the deck of a vessel for connection/splicing. Alternatively, the cables may be connected underwater using so-called "wet-mate" connectors.
The pile installation units 10 are held together using a framework 14. The framework 14 is provided with a connection plate 15 which engages with the power and control connectors on the structure 2, so that power and control signals can be transferred from the power and control cable 12 to the pile installation units 10. In one example, the connection plate 15 mimics that used for connecting the turbine 3 to the structure 2, thereby simplifying the connection procedure, since it is then the same as for the turbine 3. The connection plate can provide any suitable type of connection between the power and control cables and the pile installation units.
As shown in Figure 4, the crane 7 is operated to lift the structure 2 from the deck of the vessel 6, and to lower the structure 2 to the bed 4. The structure 2 is located at a desired position on the bed 4. When the structure has been located on the bed 4, the vessel disconnects the hoist cable 9 from the structure 2, for example using a remotely operated vehicle (ROy), and departs to perform other duties, such as installing another structure at another location.
As illustrated in Figure 5, the pile installation units 10 are operated and controlled using power and control signals supplied via the power cable 12. In one example! the pile installation units are operated at the same time, but the units may be operated in any appropriate order, to any appropriate timing schedule.
The pile installation operation may commence after the vessel 6 has departed, or may begin whilst the vessel is still on station and attached to the structure 2.
The pile installation units 10 form holes into which the piles 11 are located. The pile installation units 10 may utilise any suitable hole-forming technique such as rotary drilling, percussion drilling, or driven piles, and are supplied with electrical power via the power cable 12. Each pile 11 is secured in place in its associated hole using a grout, in accordance with known practice. When the piles 11 have been grouted in the holes, the structure 2 is effectively secured to the bed 4. In some examples, further grouting or other operations may be required in order to secure the piles appropriately for the conditions.
Following successful installation of the piles 11, a vessel (which may be the deployment vessel 6, or may be a different recovery vessel) recovers the pile installation units 10 from the structure 2. Figure 6 illustrates the recovered pile installation units 10 on the deck of the recovery vessel 6. The structure is now secured to the bed 4, and is ready to receive the turbine 3.
Figure 7 is a flowchart showing steps in one example method. At step 101, the structure 2 is located on the vessel 6. The pile installation units 10 are then attached to the structure 2 (step 102), and the vessel travels to the desired location (step 103). The power cable 12 is connected to the power connectors on the structure 2 (step 104), and the structure 2 is then lowered to the bed 4 (step 105). The hoist cable 9 is removed (step 106) and the vessel 6 then departs (step 107). The pile installation units 10 are then operated, using power and control signals supplied via the power cable 12, to install the piles 11 in the bed 4 (step 108).
A vessel then recovers the pile installation units 10 (step 109).
In another example of the present invention, the pile installation units 10 and piles 11 may be installed on the structure 2 following deployment of the structure 2 to the bed 4, rather than being installed whilst the structure 2 is on the vessel 6. In such a case, the pile installation units 10, and piles 11, are lowered together on the frame 14 to engage with the structure 2.
Splitting the lowering of the structure and drill enables a lower capacity crane 7 to be provided on the vessel 6. Such a method is illustrated in Figures 8 to 13, and steps of the method are shown in the tlow chart of Figure 14.
Figure 8 illustrates the structure 2 and installation rig 10 loaded (step 201, Figure 14) onto the deck of the installation vessel 6, ready for travel to the location (step 202). Figure 9 shows the power cable 12 attached to the structure 2, ready for the structure to be lowered to the bed 4, following connection of the power cable 12 (step 203). As before, the structure 2 may be provided with a length of cable to which the power cable 12 is connected, and this connection may be completed on the deck of the vessel 6. or underwater, before or after lowering of the structure to the bed 4.
In this example method, the structure 2 is then lowered (step 204) to the bed 4, without the installation rig, as shown in Figure 10. The installation rig is then lowered, or in the case of a buoyant rig, winched down, to the structure 2 located on the bed 4, as shown in Figure 11, and step 205 of Figure 14, for example as shown in the Applicant's United Kingdom Patent No. GB2431628.
The vessel is then able to depart (step 206) and the installation rig is then operated (step 207) in order to secure the structure to the bed 4. This stage of the process is shown in Figure 12. The installation rig is then recovered (step 208) to the deck of a vessel, as shown in Figure 13.
Examples of the present invention enable higher vessel utilisation, by allowing the deployment vessel to carry out further deployments or other tasks during operation of the installation rigs. The vessel is only needed on station for the initial deployment and for recovery of the installation rig.
Claims (1)
- <claim-text>CLAIMS: 1. A method for installing a structure on a bed of a body of water, the method including attaching an underwater power cable to the structure, providing an installation rig for securing the structure to the bed, and operating the installation rig using power and control signals supplied via the underwater power cable, wherein the power cable is subsequently used for exporting electrical power from an electrical power generator mounted on the structure.</claim-text> <claim-text>2. A method of deploying an underwater structure to a bed of a body of water, the method comprising: providing a power cable adjacent the bed of a body of water; deploying a structure to the bed; attaching an installation unit operable to create a securing hole in the bed to the structure; operating the installation unit to create at least one securing hole in the bed using power supplied via the power cable; and recovering the installation unit from the structure.</claim-text> <claim-text>3. A method as claimed in claim 2, wherein the step of attaching the installation unit to the structure occurs in advance of the step of deploying the structure to the bed.</claim-text> <claim-text>4. A method as claimed in claim 2, wherein the step of attaching the installation unit to the structure occurs after the step of deploying the structure to the bed.</claim-text> <claim-text>5. A method as claimed in any one of claims 2 to 4, further comprising connecting the power cable to a power connection unit located on the structure, and connecting the installation unit to the power connection unit.</claim-text> <claim-text>6. A method as claimed in claim 5, wherein connecting the installation unit to the power connection unit occurs substantially simultaneously with the step of attaching the installation unit to the structure.</claim-text> <claim-text>7. A method as claimed in any one of the preceding claims, wherein the structure includes a turbine receiving portion, and the step of attaching the installation unit to the structure includes engaging the installation unit with the turbine receiving portion.</claim-text>
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1122256.9A GB2497962B (en) | 2011-12-23 | 2011-12-23 | Installing underwater structures |
| PCT/EP2012/076112 WO2013092685A1 (en) | 2011-12-23 | 2012-12-19 | Off shore foundation |
| EP12809800.1A EP2795001A1 (en) | 2011-12-23 | 2012-12-19 | Off shore foundation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1122256.9A GB2497962B (en) | 2011-12-23 | 2011-12-23 | Installing underwater structures |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB201122256D0 GB201122256D0 (en) | 2012-02-01 |
| GB2497962A true GB2497962A (en) | 2013-07-03 |
| GB2497962B GB2497962B (en) | 2014-10-01 |
Family
ID=45572992
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1122256.9A Active GB2497962B (en) | 2011-12-23 | 2011-12-23 | Installing underwater structures |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP2795001A1 (en) |
| GB (1) | GB2497962B (en) |
| WO (1) | WO2013092685A1 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004015264A1 (en) * | 2002-08-13 | 2004-02-19 | Hammerfest Ström As | Guiding apparatus for subsea modules, a method and a foundation |
| GB2431189A (en) * | 2005-10-14 | 2007-04-18 | Tidal Generation Ltd | Installation of underwater anchorages |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2431628B (en) | 2005-10-31 | 2009-01-28 | Tidal Generation Ltd | A deployment and retrieval apparatus for submerged power generating devices |
| GB2448358B (en) | 2007-04-12 | 2009-07-08 | Tidal Generation Ltd | Installation of underwater ground anchorages |
-
2011
- 2011-12-23 GB GB1122256.9A patent/GB2497962B/en active Active
-
2012
- 2012-12-19 WO PCT/EP2012/076112 patent/WO2013092685A1/en active Application Filing
- 2012-12-19 EP EP12809800.1A patent/EP2795001A1/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004015264A1 (en) * | 2002-08-13 | 2004-02-19 | Hammerfest Ström As | Guiding apparatus for subsea modules, a method and a foundation |
| GB2431189A (en) * | 2005-10-14 | 2007-04-18 | Tidal Generation Ltd | Installation of underwater anchorages |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201122256D0 (en) | 2012-02-01 |
| WO2013092685A1 (en) | 2013-06-27 |
| EP2795001A1 (en) | 2014-10-29 |
| GB2497962B (en) | 2014-10-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10858075B2 (en) | Floating electrical connection system for offshore energy devices | |
| US8845235B2 (en) | Installation of underwater ground anchorages | |
| US9284709B2 (en) | Method of installing a hydroelectric turbine | |
| CN109790824B (en) | Mooring buoy for a floating wind turbine | |
| JP2010523887A (en) | Hydropower turbine deployment system and method | |
| KR101352096B1 (en) | Tripod suction pile substructure | |
| US20160312760A1 (en) | A method of managing a hydroelectric turbine array | |
| JP2018501428A (en) | Electrical system displacement system and method usable underwater | |
| AU2013100495A4 (en) | Buoy | |
| CN106382180A (en) | Floating type buoyancy pendulum wave power generation device | |
| KR20130128929A (en) | Suction pile substructure | |
| Chatzigiannakou et al. | Offshore deployment of point absorbing wave energy converters with a direct driven linear generator power take-off at the Lysekil test site | |
| GB2497962A (en) | Installing an underwater structure on a bed | |
| WO2013068410A1 (en) | Installing underwater structures | |
| WO2022108456A1 (en) | A handling apparatus and method of mating a module | |
| AU2013101562A4 (en) | Buoy | |
| EP3339630A1 (en) | A method and system of deploying or recovering a hydroelectric turbine | |
| JP2018204558A (en) | Mooring structure for power generation device, recovery method for power generation device, and arrangement method for power generation device | |
| US11981402B1 (en) | Floating system for an offshore wind turbine | |
| WO2023015254A1 (en) | Installation system and method for an offshore wind turbine | |
| CN116254872A (en) | Offshore high-efficiency construction method for steel cylinder | |
| EP3704372A1 (en) | Apparatus and method | |
| CN117684532A (en) | Portal type platform for large-scale offshore wind turbine and construction method | |
| CN111987649A (en) | Arrangement method of offshore wind field cable |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) |
Free format text: REGISTERED BETWEEN 20200924 AND 20200930 |
|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) |
Free format text: REGISTERED BETWEEN 20211014 AND 20211020 |