OFFSHOREDEPLOYMENT - Technology Vessel Inshore Jackup Vessel Semi Submersible Crane Vessel Shear Leg Barge Inshore Crane Barge In Field Support Accommo dation ... 10.50 Kn Transit

OFFSHORE DEPLOYMENTBy

Peter Blott

Technical Director – Mayflower Energy Limited

Why offshore deployment ?

Physical area required in competition with other users (population, agriculture, leisure etc)

Environmental impact (visibility, noise etc)

Size of resource (energy density)

Lack of Suitable Onshore Sites


Higher average wind speeds (up to 20% more than adjacent land)

Greater energy density (up to 73% more than adjacent land)

Size of resource (3,078 TWh/yr in Europe alone)

Benefits of Offshore Sites

Large areas available for larger (more cost effective) developments

Greater stability (40 – 60% better than adjacent land)

Lower turbulence (up to 50% longer fatigue life than similar turbines on land)

More environmentally acceptable (noise, visibility, marine life)

Opportunities for technology transfer (offshore oil & gas)


European Wind Speed & Energy Density Distribution Wind resources over open sea (more than 10 km offshore) for five standard heights

10mms-1/Wm-

2

25mms-1/Wm-

2

50mms-1/Wm-

2

100mms-1/Wm-

2

200mms-

1/Wm-2

Blue > 8.0> 600

> 8.5> 700

> 9.0> 800

> 10.0> 1100

> 11.0> 1500

Red 7.0-8.0350-600

7.5-8.5450-700

8.0-9.0600-800

8.5-10.0650-1100

9.5-11.0900-1500

Yellow 6.0-7.0250-300

6.5-7.5300-450

7.0-8.0400-600

7.5-8.5450-650

8.0-9.5600-900

Green 4.5-6.0100-250

5.0-6.5150-300

5.5-7.0200-400

6.0-7.5250-450

6.5-8.0300-600

Light Blue

< 4.5< 100

< 5.0< 150

< 5.5< 200

< 6.0< 250

< 6.5


European Offshore Wind Potential

0

200

400

600

800

1000

1200

UKDen

markFran

ceGerm

any

Irelan

d

Italy

SpainNeth

erlan

dsGree

cePortu

galBelg

ium

TWh/

year

Potential

Demand (1994)


Current & Planned European Offshore Developments

UK : 1080 Mw Denmark : 795 Mw Sweden : 3511 Mw

Netherlands : 4148 Mw

Ireland : 910 Mw Germany : 13396 Mw

France : 50 Mw

Belgium : 500 Mw

The challenges of offshore deployment

REDUCING COST !TURBINES

Increase in cost of similar size onshore and offshore machines insignificant

Increase size of turbine : reduce cost / Mw


REDUCING COST !GRID CONNECTION

Onshore : 3% of project cost

Offshore : 14% of project cost

Increase size of turbine : reduce number of connections – reduce costs

Increase size of development : larger cable – reduced costs / Mw


REDUCING COST !FOUNDATIONS



Increase size of turbine : reduced number of installations / reduced costs / Mw

Technology transfer from offshore Oil & Gas development

Monopiles

Gravity Bases

Tripods / Jackets

Re-use


REDUCING COST !INSTALLATION

Increased turbine and development size : additional emphasis on installation techniques

Inshore construction methods : limited by capacity & installation rate

Offshore (Oil & Gas) construction methods : limited by water depth, cost, & installation rate

INSTALLATION IS THE KEY !

The ‘ideal’ offshore installation system

Minimal or no external support vessels such as tugs, anchor handlers, cargo barges etc

IN FIELD SUPPORT

Sufficient for all crew for 24 hour working for long periods

ACCOMODATION

Onboard capacity for a large number of turbines & foundations

TRANSPORT CAPCapable of very accurate positioningMANOUVERABILITYMust be able to operate in very shallow waterDRAUGHTMinimal downtime due to weatherWEATHER

Able to install large numbers of turbines in short period

RATEGood capacity – min number of lifts – larger turbinesCAPACITYLow cost of mobilisation & operationCOST

Review of current installation techniques

Inshore Cranes Barges

HighIN FIELD SUPPORT

PoorACCOMODATION

MediumTRANSPORT CAP

PoorMANOUVERABILITY

FairDRAUGHT

PoorWEATHER

PoorRATE

FairCAPACITY

LowCOST


Shear Leg Barges


PoorACCOMODATION

PoorTRANSPORT CAP

PoorMANOUVERABILITY

PoorDRAUGHT

PoorWEATHER

PoorRATE

GoodCAPACITY

MediumCOST


Semi Submersible Crane Vessel (SSCV)


HighACCOMODATION

PoorTRANSPORT CAP

FairMANOUVERABILITY

V.PoorDRAUGHT

FairWEATHER

PoorRATE

HighCAPACITY

V.HighCOST


Inshore Jackup Vessels


PoorACCOMODATION

PoorTRANSPORT CAP

PoorMANOUVERABILITY

FairDRAUGHT

FairWEATHER

PoorRATE

FairCAPACITY

LowCOST


Offshore Jackup Vessels


FairACCOMODATION

PoorTRANSPORT CAP

PoorMANOUVERABILITY

FairDRAUGHT

FairWEATHER

PoorRATE

PoorCAPACITY

HighCOST


Summary of Current Offshore Installation Vessels

Offshore Jackup Vessel

Inshore Jackup Vessel

Semi Submersible

Crane Vessel

Shear Leg Barge

Inshore Crane Barge

In Field Support

Accom

mo

dation

Transport C

apacity

Manoeuvra

bility

Draught

Weather

Rate

Capacity

Cost

TIV-1

TIV-1 Characteristics

Length : 130.50 m

Breadth (moulded) : 38.00 m

Depth (moulded) : 8.00 m

Lightship : 9,240 T

Main Crane : 300 Te

Auxiliary Crane : 50 Te

Maximum Payload : 7,200 Te or 10 complete 3.50 Mw offshore turbines

6 Leg Rapid Jacking System : 60 m/hr – Maximum Wave 3.00 m (Beaufort Force 6)

8 Mw Diesel Electric Propulsion : 10.50 Kn Transit Speed + Dynamic Positioning

Minimum Operating Depth : 2.75 m

Accommodation : 50 Single Berths

Classification : DNV +1A1 MOU, EO, DYNPOS-AUT, Crane

ACKNOWLEDGEMENTSNick Goodall : British Wind Energy Association

Soren Kron : Danish Wind Energy Association

National Wind Power

Heerema Marine Contractors

Smit International

AMEC Border Wind

Greenpeace

Installation is the key

Documents

OFFSHOREDEPLOYMENT - Technology Vessel Inshore Jackup Vessel Semi Submersible Crane Vessel Shear Leg Barge Inshore Crane Barge In Field Support Accommo dation ... 10.50 Kn Transit