HAMBURG, Germany, June 13 (UPI) -- German manufacturer Siemens AG says it has deployed the first of its new generation of super-large wind turbines with an aim of improving their efficiency.
The company announced Friday it has deployed a prototype of its SWT-6.0-120 wind turbine at the offshore wind farm in Hovsore, Denmark, and is expecting big things from the direct-drive unit, which boasts a power rating of 6 megawatts and a rotor diameter of 393 feet.
The combined weight of its nacelle and rotor is less than 350 tons, which, the company says, sets "low-weight standard for large offshore machines."
The new turbine is aimed a solving a long-standing conundrum in wind technology -- the fact that the biggest offshore units are less-efficient than their smaller brethren as a measure of generating output by weight.
"In tendency large wind turbines have always been heavier per megawatt than small ones," Henrik Stiesdal, Siemens Wind Power's chief technology officer said in a release. "The SWT-6.0-120 breaks this rule having a weight per megawatt similar to that of many turbines in the 2- to-3-megawatt range."
Stiesdal said reaching the low weight "with a strong and robust machine" is the scientific holy grail wind power researchers are striving for.
Siemens' new turbine is the third developed by the company and its first giant 6-megawatt machine, which says it will "thoroughly" test and validate for performance before officially launching it for sale.
Among its benefits, Siemens says, will be to contribute to "a significant reduction in the cost of energy for offshore wind power plants," affecting not only the cost of the turbine itself but also towers and the support structures.
Siemens said it will have the same type of blade as its 3.6-megawatt machines, which are manufactured without glue joints.
The prototype is to undergo "extensive commissioning and trial operation." Siemens says it will install other SWT-6.0-120 prototypes this year and will test them until 2013 with full-scale production planned for 2014.
With the Friday announcement, Siemens joins the French engineering giant Alstom in developing a new 6-megawatt wind turbine. That company said in March it will collaborate with Belgian wind farm developer Belwind to demonstrate its next-generation unit.
The company says it's seeking EU funding for the project under the NER300 program, which is funded by the sale of emissions allowances through the EU Emissions Trading System.
The European Investment Bank says it expects to begin the sale of 300 million carbon permits worth $7.2 billion as soon as EU member states vote to approve the sale, which is expected this month.
Alstom's prototype would be part of the second phase of a 40-megawatt offshore plant to be developed from 2012-15 on the Bligh Bank, near the Belgian port of Zeebrugge in Flanders.
Like the Siemens effort, Alstom's new turbine has been designed to cut upfront costs by reducing the weight of the entire structure yet be able to stand up to harsh offshore weather.
Costs are further reduced by simplified construction techniques maintenance and repair procedures.
The world's biggest wind turbine -- the Enercon E-126 -- is a 7-megawatt onshore behemoth with a rotor diameter of 413 feet built in 2008 near Emden, Germany. Prototypes for 10-megawatt turbines are being developed by the Norwegian government and the British company Clipper Wind Power, which is also seeking funding from the NER300 program.