Offshore, Project Development, Wind Power

Technology Spotlight: Wind Turbines

At the recently held EWEC 2009 wind energy conference and exhibition most exhibitors agreed that while there has been a substantial business slowdown due to problems linked to obtaining wind project financing, an upturn in demand during the second half of 2009 is beginning to play out, at least in the U.S. Other exhibitors were a bit more cautious pointing out that substantial numbers of unsold turbines from framework contracts failing to secure project finance are now floating on the wind market.

New Technology Trends

In what many wind industry insiders consider a major development trend, French aerospace companies EADS Astrium & EADS Composite Aquitaine announced their formal entrance into the wind industry. The French companies offer the wind industry advanced composite materials engineering, manufacturing and related know-how as well as rotor-blade manufacturing capacity.

Civil engineering contractor Ballast Nedam of the Netherlands presented a One Lift Concept whereby a complete offshore wind turbine (nacelle  + rotor  + tower) can be picked up and installed at sea on a ready-made foundation structure. The One Lift system itself is fitted upon the huge company-owned Svanen installation vessel.

In terms of new product developments the actual number of multi-megawatt sized wind turbines presented in Marseille was modest, but several suppliers displayed fresh details of their latest existing products.

German company PowerWind was one of few that introduced a new product. Its 2.5-MW gear driven PowerWind 90 (rotor diameter 90m) expands the current product range that comprises a single 900-kW model.

Siemens Energy also introduced its new SWT-2.3-101 model, which the company says is ideally suited for low- to medium-wind speed sites. Siemens expects the low- to medium-wind market segments to grow substantially in the future, representing as much as one third of the total global wind power market in the coming years.

Vestas of Denmark announced a new 3-MW V112-3.0MW (rotor diameter 112m) as well as a V100-1.8MW turbine. Details presented at the show indicate that the 1.8-MW turbine model builds on the V80-2.0MW platform. In addition to its 100-metre rotor,  it incorporates a huge cooling radiator on top of the box-type nacelle. The V112-3.0MW features a similar looking nacelle and nacelle-top cooling arrangement, which appears to be the company’s new style for 2009.

Most interesting from a wind technology point of view is the V112-3.0MW switch away from a compact V90-3.0MW integrated gearbox and main bearing assembly to a 3-point gearbox support. The application of a permanent magnet (PM) type generator with full converter system in the V112-3.0MW is new for Vestas but not for the wind industry. These generators are already applied by a range of suppliers in product like the Clipper Liberty series, the GE (2.5xl), and 2-MW Unison U-88/U-93 series. However, opinions are mixed on the application of these PM generators in wind turbines, and especially on the limited long-term track record.

Global Wind Power (GWP) of India plans to erect a new direct-drive 2-MW prototype within the next few months in the Netherlands. The turbine, named GWP-82 – 2000-kW, has been developed by Dutch wind pioneer Henk Lagerwey and his design team and incorporates — among other features — a “passive air-cooled” fully enclosed PM generator.

Seven technical experts discussed a range of subjects during a session entitled “taking wind power to the next level.” The discussion ranged from future generator trends to perceptions on the optimum size of wind turbines for onshore and offshore applications. In addition, wind turbine reliability aspects, main cost drivers, and from which wind industry angles major technological breakthroughs can be expected were also discussed.

Look for an in-depth magazine article on wind turbine technology trends in the next issue of Renewable Energy World magazine.

NEW!  Join us for a unique online live chat with Eize de Vries on Wednesday, April 15th at 10:30 Eastern Daylight Time (14.30 GMT / 16.30 European Summer Time).  You’ll have the opportunity to ask our wind technology expert questions about developments in new wind energy generation technologies.  Don’t miss it!