In a recent chat with turbine blade supplier LM Wind Power, I learned that the company will develop what they say is the “longest turbine blades ever produced.” The company is partnering with French Alstom, which provides power generation equipment services, to develop the blade designed to fit its 6-MW turbine for the European offshore market.
This blade will require more than 20,000 hours of work, focusing on aerodynamics, structural design, and production. Using glass fiber and polyester will enable the blades to be considerably light for their length. The blades will be tested in LM Wind Power’s wind tunnel. Prototype blades will be produced in the company’s Danish factory in Lunderskov, also currently manufacturing the LM 61.5-m blades, and will be ready for installation at Alstom prototype sites in Europe over the winter 2011 to 2012. LM Wind does not yet know if the blade will be offered in the U.S. Communications Specialist Lene Mi Ran Kristiansen says it will depend on Alstom’s plans. Most likely France, UK, and other North Sea markets are what they will focus on.
As for the turbine, Alstom reports its model has a large rotor diameter and 6-MW power output. The turbine’s weight also reduces installation and infrastructure costs. It features what Alstom calls “pure-torque technology” to protect the generator and improving its performance. The technology protects the turbine’s drive train by deflecting unwanted stresses from the wind safely to the tower. Only turning force, or torque, is transmitted to the generator thereby boosting the turbine’s reliability. Furthermore the turbine’s permanent magnet direct drive system enables a compact, lightweight design that reduces service costs and improves operating efficiency. The system’s low number of rotating parts increases reliability, to maximize turbine availability and further reduce maintenance costs.
Unfortunately, Communications Specialist Lene Mi Ran Kristiansen says Alstrom prefers not to share details of the blade’s length or rotor size due to the competitiveness of the offshore wind market. Roland Sundén, chief executive officer at LM Wind Power Group says the new blade builds on features developed for the company’s recent blade launch, the GloBlade, which offers an additional annual energy production of 4-5 % compared to standard blades.