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Husum WindEnergy welcomes offshore wind sector

Adam Westwood, David Hopwood

As one of the largest wind events on the global stage approaches, the big wind companies continue to flex their muscles on the offshore wind stage.

2008 and 2009 are expected to be boom years for the offshore wind sector in Europe — with the planned commissioning of a total of 1507.5 MW of new installations coming online.

The European Wind Energy Association (EWEA) predicts that, by the end of 2010, cumulative offshore wind capacity of between 3000 and 4000 MW will be operational off the coasts of Europe. And outside of Europe, countries such as the USA and China have announced plans to exploit their own offshore wind potential. According to a study by the National Renewable Energy Laboratory (NREL), the offshore wind energy potential of the USA is more than 1,000 GW.

But what companies are currently active in the offshore wind sector? The supply of offshore wind turbines is currently dominated by Vestas (with a market share of about 60%) as well as Siemens. At the beginning of 2007, Vestas had to withdraw the V90- 3 MW turbine from the market for technical reasons, but released the machine again from May 2008 onwards. And at the beginning of March, the Dutch developer Evelop selected Vestas for the supply of 110 turbines (V90-3 MW) for its Belgian, 330 MW offshore wind project Belwind.

At the end of 2007 Siemens had offshore wind turbines in operation with a total capacity of 434 MW, and plans for more than 1,080 MW in new portfolio projects.

In 2007 the company installed 25 offshore wind turbines — in the 3.6 MW category — off the British coast, at the Burbo Banks wind farm. A UK project with 180 MW will be completed in 2008, and at least three more projects off the British and Danish coasts are planned for 2009, with a combined capacity of some 400 MW.

In addition, a number of other companies are joining the competition for the commercial supply of offshore 5 MW turbines in 2008. German companies REpower and Multibrid have each developed a 5 MW wind turbine for the offshore field. Each of these companies has been operating a prototype on shore since the end of 2004, and the turbines are now ready for series production.

Rapid international expansion in this sector is expected, following the acquisition by the French nuclear group Arreva of 51% of Multibrid's shares — from the German project developer Prokon Nord in 2007. This year, a first batch of 6 Multibrid, 5 MW wind turbines will be installed at the German offshore test field Alpha Ventus. And REpower will install another 6 wind turbines of this category at the same place in 2009. REpower was also the first company in the world to install 5 MW wind turbines in “real” offshore operation — two of these are installed off the Scottish coast, in a record water depth of 44 metres. Another 60 turbines are currently in the initial project phase, for C-Power's 300 MW Farshore windfarm off the Belgian coast. A scaled-up 6 MW model will be launched in the next few years.

A joint venture with wind turbine rotor blade manufacturer A&R Rotec will start operations in Bremerhaven, Germany in the near future. The PowerBlades project will produce 61.5 m offshore rotor blades, developed by REpower.

Other companies are similarly active in the offshore wind sector. Converteam, for example, is a key partner in the Dutch, 4.7 MW DarWinD offshore turbine project, and will supply the direct drive generator.

Nordex of Germany is operating a 2.5 MW wind turbine at the port of Rostock, and will deliver another 21 units for Baltic I, Germany's first commercial windfarm. This 52.5 MW project is scheduled to go online in 2009. Nordex decided to enter the offshore sector on a step-by-step basis, starting with the development of a new 3 to 5 MW wind turbine with “offshore features”. A prototype is to be built in 2010, and the 0 series by 2011/2.

WinWinD of Finland has installed three of its 3 MW Multibrid type wind turbines on artificial islands in the Kemi Ajos wind farm — close to the shore.

And Dutch company Blue H Technologies will provide information on its innovative “floating” offshore wind turbine technology at HUSUM. A prototype is currently being tested off the Italian coast. The next (pre) series model will feature a two-blade in-house modified 2.5 MW wind turbine.

Project update — offshore wind

Eon and DONG Energy have bought out Shell's share of the London Array offshore wind project for an undisclosed sum. The deal sees the two companies become equal partners in the project. At the time of the deal, the companies stated that they still hope for completion of phase 1 by the end of 2012, subject to securing important contracts, such as turbine supply. The project's time scale has increasingly been seen as optimistic given the current supply & demand imbalances in the industry, particularly with relation to turbines and installation. With major contractors already booked-up for the period, it is currently difficult to see how the proposed time scale can be met. There is, however, some encouraging news in relation to installations in the wider market.

In mid-July, the German project Alpha Ventus received its final permissions from the Federal Maritime Hydrographic Agency (BSH). Installation of the tripod foundations manufactured by Aker Kvaerner in Norway has now begun. Funding of €50m has been given by BSH for this demonstration project, which will consist of 12, 5 MW wind turbines. Six are Multibrid M5000s and these will be installed and delivering power by autumn. In 2009, 6 Repower 5M turbines will be installed.

The project (formerly known as Borkum West) is developed and owned by joint venture DOTI, equally owned by Eon, Vattenfall Europe and EWE. Its stated cost is €180 million. The 70 km long grid connection is being provided by Eon Netz and forms part of a €74m infrastructure development, already underway.

The first wind turbines have now been installed at C-Power's Thornton Bank project. The 30 MW project, located 30km off Belgium, will see 6 Repower 5M wind turbines installed this year in the first of three phases. It will be the first commercial offshore wind project using 5 MW wind turbines. It also heralds the start of a promising offshore wind market off Belgium. Whilst lacking the high number of project proposals of other European countries such as the UK, Germany or the Netherlands, there is marked progress with Belgian developments moving forwards.

MPI Offshore, operators of the Resolution turbine installation vessel have placed orders with the Cosco Nantong shipyard in China for two new vessels. The order, worth over €300 million will see two larger vessels of similar design to the existing one (which cost less than half of one of the new vessels). The vessels will be 137 m long, with accommodation for 112 crew, a helicopter landing deck, and improved jacking and positioning capability. They will be able to operate in water depths of up to 40 m, due to jacking legs that are 72 m long, giving them the potential to work on the majority of planned European projects. MPI states that the MPI Adventure will be available for work from spring 2011, and the MPI Discovery should be commissioned by autumn 2011. MPI has options to build a further two vessels at the yard.

The Netherlands' largest offshore windfarm, supplying approximately 435 GWh of electricity is now operational. The Princess Amalia Wind Farm, previously known as Q7, was opened by the Dutch energy companies Econcern and Eneco. The 60 wind turbines of 2 MW each are situated 23km from the coast in block Q7, off Ijmuiden at depths of 19–24m. It is said to be the world's largest wind farm outside the ‘12 mile zone’, and located the furthest from the coast and constructed in the deepest water.

And finally, as we go to press, BERR has approved two major new windfarms, including the 315 MW offshore windfarm, Sherringham Shoal. It will be situated 12 miles off the Norfolk coast and is being developed by Norwegian utility company StatoilHydro and Dutch energy company Evelop. When fully operational it will have 88 wind turbines. It is expected to be operational by 2011. It is the fourth largest offshore windfarm approved in the UK

Project update — wave and tidal

Wave Hub, the pioneering wave energy concept that would allow multiple technologies a single shared connection point, has been scaled back. The facility was proposed as a 20 MW scheme but this has now been reduced to 8 MW initially. This is due to technical advice against the use of untested subsea transformer units. This news follows previous statements which have declared tenders received for the construction of the facility as too expensive. Under a single-contract package, tenders received were in excess of £30m. A new tender package will be sent out under a multiple-contract approach towards the end of the year with contractors chosen in spring 2009. The delays means that completion will not be until 2010.

Once built, Wave Hub will later be upscaled when the transformer technology is proven. The original 33kV grid connection will be installed as planned to support the later expansion.

The number of devices now expected to be installed from each technology developer has not yet been announced. Companies chosen for the facility are Ocean Power Technologies, Oceanlinx, Fred Olsen and Westwave (a development consortium using Pelamis Wave Power technology).

Listed wave energy developer, Ocean Power Technologies Ltd has signed a Berth Agreement with the European Marine Energy Centre (EMEC) in Orkney, Scotland. In 2007, OPT was awarded a grant by the Scottish Government for the construction and installation of its PB150 PowerBuoy at EMEC. The Agreement provides for the deployment and operation of the PowerBuoys and grid connection. OPT may further utilise the berth as a possible site for deployment and test of future PowerBuoys.

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Wave and tidal energy  •  Wind power