Page 37: of Maritime Reporter Magazine (October 2002)

Sea Technology

The "Cost" of Wind

Cost of various electricity generation technologies, in cents kW/hr.

Mayflower Resolution Main Particulars

Classification DNV +1A1, Self-elevating Unit, EO

DYNAPOS-AUT, Crane

Number of Jackup Legs 6

Flag State Isle of Man

Range 25 Days - Full Crew / Deck Load

Length 428 ft, (130.5 m)

Breadth 125 ft. (38 m)

Depth 26 ft. (8 m)

Type/Number Offshore Wind Turbines 10

Maximum Payload 3,000 Te Jacking

Main Crane - Max Capacity 300 Te@ (25.5 m) 250 Te@ (29.5 m) 240 Te@ (30.5 m) 200 Te @ (35 m) 50 Te @ (80 m)

Accommodation 50 Single Berths

Operating Conditions

Jacking Operations 3 m maximum wave

Jacked Survival 100 Year Storm (Force 12 Beaufort

Scale) 50-year wave 14.0 meters

Minimum Operating Depth 10% Cargo 7 ft. (2.2 m)

Minimum Operating Depth 100% Cargo 10 ft. (3.2 m)

Max Operating Depth 35 m (increase possible)

Transit Speed 10.5 Knots

Jacking Capacity 2,500 Te per leg

Holding Capacity 3,500 Te per leg

Jacking Speed lm/min

Max. Draft Loaded 9 ft. (3 m)

Max. Draft Lightship 8 ft. (2.4 m)

Source

Coal

Gas lurbine

Nuclear

Good wind site

Optimal wind site

Generation Cost 3.11-3.41 2.53-3.41 3.31-5.74 5.84 3.89

Est. External Cost of Generation* 1.94-14.6 0.97-3.89 0.19-0.58 0.05-0.24 0.05-0.24

FOR SOME VERY GOOD REASONS

THE HAMMAR H20

HYDROSTATIC RELEASE UNIT IS

Circle 209 on Reader Service Card or visit www.maritimereporterinfo.com mitigate the risks associated with working in the

North Sea, giving an installation solution by focus- ing on the following criteria: the vessel must be highly maneuverable, dynamically positioned, high speed jacking capability all of which will increase the vessels operating potential.

In transit, carrying wind turbines from base to offshore site, and in maneuvering into position for jacking, the Mayflower Resolution will be driven by a diesel electric system powering four azimuth thrusters and three tunnel thrusters

The Mayflower TIV will be able to carry the components for ten wind turbines of 2 to 3.5MW rating. Typically the towers will be in two tubular sections about 98 - 164 ft. (30-50 m). These will be lowered in turn on to a prepared foundation rising a few meters above sea level and bolted together.

The heavy gearbox/generator in the nacelle will then be installed on the tower, using the installation vessel's main crane with a capacity of 300 tons at 25.5 m radius and 110 m hook height. The three blades will be assembled on the hub on board the vessel, using a smaller 50-ton crane, and the unit will then be installed on the nacelle.

A transit speed of 10.5 knots will enable the ves- sel to shuttle to and from the base collecting the next batch of turbines with the minimum use of time, and also travel between jobs. On site, and jacked up, it will be able to sit out the 100 year storm, and the 50 year wave (Beaufort force 12, and 14 m height). Between wind energy contracts, the TIV is likely to attract offshore oil and gas con- tracts such as shallow water platform renewals.

The whole of the aft part of the vessel, (1,750 sq. m.), is available for transporting, assembling and manipulating turbine components, with additional space for the tower sections themselves in racks along the sides between the hydraulically operated legs. A total payload of 7,200 tons can be carried, and the working deck is stiffened for 10 t/sq. m. loading and 50-ton forklift trucks. The minimum operating water depth is 7 ft. (2.2 m) with 10 per- cent cargo on board, increasing to 10 ft. (3.2 m) with a full load.

Mayflower Resolution will have accommodation for 50 people in single berth cabins, and all facili- ties for a 60-day endurance, arranged in the for- ward mounted superstructure, with the bridge above. This unusual vessel will be classed by DNV with Self Elevating Unit and Dynpos AUT nota- tion, and will be cleared for worldwide operation.

Graig Shipping has provided a full support pack- age for the supervision of the building of

Mayflower Resolution at China's Shanhaiguan yard. "Chinese shipyards are now first choice for new vessel types," says Hugh Williams, CEO of

Graig. "Not only are they competitive on pricing, but they are flexible and willing to adapt to new technology and new designs. We are very happy that we have been able to help Mayflower find the right yard, the right designer and the right classifi- cation society to get this new offshore industry off to a good start." Graig advised Mayflower on choice of yards, introduced Denmark's Knud E

Hansen as the designer and DNV as a suitable class society, and assisted in yard negotiations. Graig's

China-based supervision team will now oversee the building and delivery of the first vessel, which is due to enter service in February 2003.

The vessel — originally known as the TIV-1 and to be offi- cially named Mayflower Resolution — was developed by

Knud E Hansen in Denmark and incorporates a host of new marine technologies.

HAMMAR*

KEEPING YOU AFLOAT IS OUR BUSINESS

Phone +46 31 709 65 50, Fax +46 31 49 70 23 lnfo®cmhammar.com, www.cmhammar.com

Rod weakllnk break* and survivors can board the Inflated • Revised model with a single point connector for painter line • Simple to Install, safe and has a more effective construction • It needs no service or maintenance • Fits all llferafts * EPIRBs of all shapes and sizes • It's approved by most shipping authorities

Hammar H20 secured to lifer aft cradle and attached to llferaft lashing with sllphook.

Painter line shackled to weakllnk and strong rope with single point connector.

If the vessel sinks, the water pressure will activate the sharp knife which cuts the strong rope that holds the lashing and the llferaft will float free.

As the vessel sinks, the palnterline will be stretched and the llferaft starts to

Inflate.

October, 2002 37