Commercial, Products

Offshore Wind Farms: Powering Europe’s Future

By By Andrew Drwiega, Helitech 2011 Conference Chairman and Rotor & Wing Military Editor | September 27, 2011
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In 2002 Vattenfall (then ELSAM) awarded Danish helicopter operator UniFly the contracts for hoist operations to the Horns Rev field.  The existing contract, signed in 2007, runs for five years.

The business opportunities for global helicopter operators in supporting the offshore wind farm power generation market, especially within Europe, are set to expand rapidly over the next couple of decades. In fact the growth has already begun and there are now plans for offshore farms containing over 1,000 turbines covering a large area of sea.

Within the United Kingdom, Bond Air Services has already been awarded the first helicopter contract to service the Greater Gabbard wind farm in the North Sea and competitor Bristow has also announced its intent to compete in Europe with a range of flexible services. Danish helicopter operator UniFly services the Horns Rev I and II wind farms off the Danish coast transporting technicians for maintenance and occasionally types of cargo, especially when the sea is to rough for boat transits. Back in 2002, UniFly was awarded a contract for hoist operations at the Horns Rev 1 offshore wind farm. UniFly uses the Eurocopter EC135 and in 2009 Bond Air Services also bought one of the same aircraft to serve the Greater Gabbard field. UniFly claims to have been the first helicopter operator to begin hoisting people onto wind turbines. In 2009, DONG Energy brought its Horns Rev wind farm online with a mere 91 turbines (generating 2.3MW each), yet at the time was the largest wind farm in the world. Siemens supplied the turbines, which stand 114.5 meters tall with another 30-40 meters under the surface of the sea. The diameter of each rotor is 93 meters and the area covered by the field is around 35km².

Danish DONG Energy's 90-MW Burbo Bank wind farm

The power created by wind energy in Europe is set to triple by 2020, according the European Wind Energy Association (EWEA) Pure Power report published in July. The EWEA’s policy director, Justin Wilkes, revealed that “€194 billion will be invested in European onshore and offshore wind farms in this decade.”

Later this year the European Union will be publishing its long-term prediction for wind energy, the European Commission’s Energy Roadmap 2050. Europe has grasped wind energy, with many countries seeing it as a “green” alternative to fossil fuel fired power stations.

According to the figures wind power produced electricity should increase from 182 Terawatt hours (TWh) or 5.5 percent of the total EU demand in 2010, to 581 TWh or 15.7 percent of the total demand in 2020. The prediction from the EWEA is that “by 2020 the electricity production from wind energy will be equivalent to the total electricity consumption of all households in France, Germany, Poland, Spain and the United Kingdom together.”

Denmark is leading in terms overall wind power provision for its own energy needs, not only in the EU but worldwide, meeting 26 percent of its energy consumption in 2010. Spain and Portugal derive around 15 percent of their national requirements from wind energy with Germany achieving 8 percent and the UK only 3.7 percent.

In fact, by 2030, 28 percent of the total European requirement (1,154 TWh) would be generated through wind power, which the EWEA says is more than the 241 million private households are expected to need that same year. Today the figure is closer to 50 million households, indicating a huge increase in just under two decades.

In offshore terms, 2.9 GW was installed at the end of 2010 accounting for 3.5 percent of installed EU wind energy, a rise from 2.7 percent in 2009 and representing 9.5 percent of new annual capacity.

In 2010 offshore wind accounted for 20.5 percent (€2.6 billion) of the total EU investment generating 883 MW.

Although Denmark has been the leader in offshore wind power development, in 2010 it was overtaken by the United Kingdom, which exceeded a capacity of 1 GW.

Eight EU countries together with Norway now have installed offshore capacity.

Research and development into generator capacity and the increase in size of the wind turbine rotors over the last two decades have been responsible for a relatively dramatic growth in average turbine capacity.

In 1991 it was around 200kW onshore and 450 kW offshore in 1991. By 2010 this had risen more than 1,700 kW onshore and 2,800 kW offshore.

Hoisting from a turbine in the Horns Rev offshore wind farm, Denmark.

During the late summer the EWEA released its key trends and statistics review for the first half of 2011 regarding offshore installations. These showed a 4.5 percent increase in installations compared with the first half in 2010, with 101 offshore wind turbines being installed that could generate around 348.1 MW. These sites belonged to the UK, Germany and Norway. In total 11 offshore wind farms are under construction and when finished will supply 2,844 MW.

The number crunching statistics alone make for impressive reading:

• There were 1,247 offshore wind turbines on June 30 in 49 wind farms over nine different national areas. The turbine wind farms were in the following areas: Greater Gabbard and Walney 1 in the UK; Baltic 1 and BARD Offshore 1 in Germany; and the fourth prototype floating turbine in Bergen, Norway,

• 129 foundations were installed in seven offshore areas: Thornton Bank 2 in Belgium; Walney 2, lincs, London Array and Sheringham Shoal in the UK; BARD 1 in Germany and the Norwegian floating prototype,

• 108 turbines were installed, and

• finally, preliminary work was carried out at Gwynt y Mor and Teesside in the UK; Raahe and Thornton Bank 3 in Belgium.

There are two main turbine manufacturers supplying wind turbines to this EU area. By far the largest is Siemens with an 84 percent share of the grid connection against BARD Emden Energy, whose share is 16 percent. A third turbine manufacturer is SWAY but to date has only been responsible for the floating turbine at Bergen, Norway.

Financing in this sector is becoming stronger. Germany’s largest offshore find farm project looks to have secured the €1.2 billion investment it requires when construction begins in 2013.

The Meerwind Sür and Meerwind Ost offshore wind farms, owned by German company WindMW, will be sited in the German Bight around 23km north of Helgoland island. With 80 wind turbines, the Meerwind site is expected to generate around 288 MW. Power will be fed into an internal transformer platform sited within the wind farm, which will in turn be connected to the German national grid. The site will be supported and maintained from nearby Helgoland and construction is expected to begin within the next two years and completed by the end of 2013.

EWEA says the trends are good for offshore wind farm financing. Banks are now more willing to look at offshore wind power generation in a new light, and there have been positive moves forward in Germany, Denmark and in the UK. However, there is a final cautionary word from Christian Kjaer, chief executive officer of EWEA: “While I see several positive trends for the European offshore wind power industry, we are not home and dry yet,” he says. “The sector is coming out of the financial crisis but is still facing a potential worsening of the general economic crisis. The number of banks providing capital for offshore wind farm investments is steadily growing, although there is a continued need for attracting an increasing number of large institutional investors to offshore wind farms—presently the largest construction projects going on in Europe.”

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