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November 2012 Issue

Inclement Weather Causes PowerBuoy Deployment Delay
Pennington, New Jersey-based Ocean Power Technologies Inc.'s (OPT) PowerBuoy off the coast of Reedsport, Oregon, is now expected to be deployed in spring 2013, instead of later this year, as previously scheduled because of weather-related concerns. Final testing of the PowerBuoy remained on track for completion.

Assembly and readiness for deployment was scheduled to occur in October, after which, subject to weather conditions, OPT had planned to tow the completed device approximately 300 miles from a Portland, Oregon, dry dock to its deployment site 2.5 nautical miles west of Reedsport. However, the early onset of unfavorable weather conditions has affected the installation of moorings. In addition, uncertainty regarding weather conditions during the October time frame increased the risks of incurring substantial deployment vessel standby costs and adverse safety conditions while transiting the buoy from the dry dock to the deployment site.

The buoy is designed to perform well during severe weather once installed, but during transit there are concerns for towing stability in harsh conditions.

'In light of the increased weather, safety and cost risks, it is the right decision to plan for deployment next spring,' Charles Dunleavy, CEO of OPT, said. 'We are not prepared to compromise the safety of crews or their vessels, or the OPT PowerBuoy system itself en route to the site and during the deployment and commissioning.'

Furthermore, following deployment there is a required period of time for commissioning the PowerBuoy for full operation, which also may need some level of marine operations.

The PowerBuoy, which incorporates a direct drive power take-off system, will be the first of up to 10 proposed devices licensed by the Federal Energy Regulatory Commission for the grid-connected Reedsport OPT Wave Park. The 1.5-megawatt project could power about 1,000 homes.

Sheringham Shoal Wind Farm Opens Offshore Norfolk, England
The Sheringham Shoal Offshore Wind Farm off the coast of Norfolk, England, was officially opened in September. Sheringham Shoal is owned equally by Statoil (Stavanger, Norway) and Statkraft (Oslo, Norway) through the joint-venture company Scira Offshore Energy Ltd. (Norfolk).

The opening took place four years after Scira was granted consent by the U.K. government to build the wind farm and three years after construction began. Scira has been preparing for the operational takeover for the past three years, and about 60 local people are employed full-time to operate and maintain the wind farm.

Sheringham Shoal has 317 megawatts of capacity and covers an area of approximately 35 square kilometers. It has 88 wind turbines, each with a capacity of 3.6 megawatts, that will generate 1.1 terawatt-hours per annum. The turbine blades are each 52 meters long, and the turbine towers are 80 meters high.

The wind turbines are placed on monopile foundations piled into the seabed. There are two 900-tonne offshore substations, two 132-kilovolt marine cables that come ashore at Weybourne, England, and 21.6 kilometers of underground cable connecting to a new substation at Salle, England.

From this substation, the power is transported to Norwich, where it enters the national grid.

The completion of Sheringham Shoal means the U.K. now has more than 2.5 gigawatts of operational offshore wind energy capacity. The wind farm will supply power to 220,000 homes.

Wind Turbine Rotor With World's Longest Blades Begins Testing
Siemens AG (Munich, Germany) began field testing in October its 154-meter rotor for the 6-megawatt offshore wind turbine in østerild, Denmark, at the new national test center. The SWT-6.0-154 turbine is equipped with the world's longest rotor blades, each 75 meters long.

With a 154-meter rotor diameter, each turbine can produce 25 million kilowatt-hours of electricity that could power 6,000 households.

The SWT-6.0-154 is the lightest turbine in its class, having a nacelle weight of 200 tons.

To manufacture the B75 blade, Siemens uses its IntegralBlade process, which produces a blade up to 20 percent lighter than traditionally manufactured blades. The B75 blade's high stability and low weight helps lower the cost of wind energy.

The first Siemens 6-megawatt turbine was installed in May 2011 at the Høvsore, Denmark, test site. Due to height restrictions, a 120-meter rotor was used on the prototype. It has now operated more than a year.

In July, Siemens entered into a master agreement with DONG Energy (Fredericia, Denmark), for the delivery of 300 offshore SWT-6.0-154 turbines. They are expected to be used in projects off the coast of the U.K.

Bechtel and Subsea 7 to Develop Offshore Wind Projects Jointly
Bechtel Corp. (San Francisco, California) and Subsea 7 (London, England) announced in October that they will work together as part of a non-exclusive joint approach to develop offshore wind and associated transmission projects in Europe, including the U.K. and Germany.

Bechtel and Subsea 7 will engage with key stakeholders in the market and evaluate prospective project opportunities on a case-by-case basis. The companies will continue to pursue opportunities separately in the offshore wind and transmission sector where the scope of work is segmented in multicontracting arrangements.

Bechtel is presently building and managing the construction of approximately 850 kilometers of new transmission lines and substations in parts of Canada.

Subsea 7, which established its offshore renewables division in 2011, is part of the Offshore Wind Alliance along with SSE (Reading, England), Siemens Wind Power A/S (Brande, Denmark), Siemens Transmission and Distribution Ltd. (Manchester, England), Atkins (Epsom, England) and Burntisland Fabrications Ltd. (Burntisland, Scotland).

Subsea 7 is also active in the offshore wind installation market through its joint-venture company Seaway Heavy Lifting (Limassol, Cyprus).
2013:  JAN | MARCH | MAY | JULY | SEPT | NOV
2012:  JAN | MARCH | MAY | JULY | SEPT | NOV

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