BOEM.gov

CVOW-C Offshore Wind Farm

CVOW-C Project ConstructionInstallation of Foundations • The Wind Turbine Generator (WTG) Foundation concept

consists of two parts, a lower foundation pile (monopile) driven into the seabed and an upper transition piece mounted on top of the monopile, referred to as the WTG Foundation.

• Installation of the WTG Foundations would entail lifting, upending, and placement of each WTG Foundation at its construction and installation location.

• A two-part WTG Foundation would comprise a monopile with grouted or bolted transition piece or a single part, continuous monopile integrated with the transition piece.

• The WTG Foundations would have scour protection installed around the base of the monopile.

Installation of Wind Turbines • The WTG construction and installation process consists of

the load-out, offshore transport, mechanical erection, and offshore commissioning of the WTGs.

• Depending on the water depth at the WTG construction and installation location, one or two-layers of scour protection would be required. Scour protection would consist of large rocks sourced from the U.S. and/or Canada and would be installed with either a jack-up vessel (JUV) or dynamically positioned (DP) vessel equipped with a fallpipe.

• The monopile would be placed on the seabed on top of the pre-installed scour protection layers and driven to the target depth of penetration by an onboard hydraulic hammer, which is guided by the pile gripper.

• Monopiles would be installed by either one or more dynamically positioned heavy lift vessels (HLVs) or JUVs.

• Monopiles would be installed in one or more years between May 1 and October 31 to avoid the North Atlantic right whale migration season.

• WTG construction and installation activities are anticipated to last up to 30 months.

Offshore Substations • A piled jacket foundation would be used to support the

offshore substations.

• Construction and installation of the offshore substation topside would take place following the construction and installation of the piled jacket foundation.

• After the offshore substation topside is brought to the site, the topside would be lifted and placed on the foundation via a crane on a floating HLV or floating crane vessel. The topside would then be welded or grouted to the foundation.

Cable Laying • The target cable burial depth is 4 to 6 feet.

• Cable installation methods would include jet trenching, chain cutting, trench former, hydroplow, mechanical plowing, pre-trenching, mechanical trenching, and/or other available technologies.

• A narrow temporary trench would be created, into which the cable is fed while the equipment is towed along the seabed. The cable burial equipment rests on skids or wheels.

• The final installation methods and target burial depths would be determined by the final engineering design.

Offshore Wind Turbine Installation

245

° 28

5°

N

EXTERNAL PLATFORM

BOLTING PLATFORM

INTERMEDIATE PLATFORM

INTERFACE FLANGE

BOAT LANDING LADDER WITH

UPPER EXERNAL LADDER

BOAT LANDING FENDER

SERVICE CRANE

SINGLE LINE GROUT PIPE

ICCP CABLE PIPE

ICCP ANODE (x6)

GROUT DISTRIBUTION CHANNEL

UPPER ICCP DISTRIBUTION PIPE

TRANSITION PIECE

LAYDOWN AREA

LOWER ICCP DISTRIBUTION PIPE

GUARD RAIL

WALKWAY

DOUBLE GATES (x3)

SCOUR PROTECTIONFILTER LAYER

SCOUR PROTECTIONARMOR LAYER

Ver. Date Prepared Checked Approved Description

1 2020-12-11 SEP/TPRO KENS OBL ISSUED FOR INFORMATION

245

° 28

5°

4321

C

1 2 3 4

A

B

D

E

F

E

B

A

D

F

C

1Ver.

1690016328-CVOW-C-419-WTG-SS-01-006NOTED A1Drawing No.SizeScale

COASTAL VIRGINIA OFFSHORE WIND COMMERCIAL

Project Number

Project Name

Client

1690016328

GENERAL ARRANGEMENT3D VIEW - WITH SCOUR PROTECTION

Title

ALL RIGHTS STRICTLY RESERVED. REPRODUCTION OR ISSUE TO THIRD PARTY IN ANY FORM WHATEVER, IS NOT PERMITTED WITHOUT WRITTEN AUTHORITY FROM THE PROPRIETOR.

NOTESKEY-PLAN

DAVIT CRANE

CL BOAT LANDING

FOR DESIGNERS REQUIREMENTS SEE REPORTS:1.CVOW-C-3_2_3_1-001 FOR MATERIALS AND FABRICATION AND CVOW-C 3_2_3_1-002 FOR COATING.

ALL ELEVATIONS ARE RELATIVE TO M.S.L.2.

THIS DRAWING IS PRELIMINARY AND IS SUBJECT TO CHANGE 3.DEPENDING ON THE DETAILED DESIGN.

Illustrative Example of the WTG Foundation

For more information on BOEM’s Renewable Energy Program, visit www.boem.gov/Renewable-Energy