A mighty investment wind propels composite turbine blades in 2009

(NREL) National Wind Technology Center (NWTC) outside Boulder, CO as part of what the participants call “the biggest government-industry research partnership for wind power generation ever undertaken in the U.S.” The 331-ft-diameter rotor, mounted atop a 262-ft tower, is among the largest land-based turbines deployed in the U.S. and is the biggest at the NWTC site. Siemens and NREL’s Cooperative Research and Development Agreement (CRADA) will test the pilot turbine’s performance over a minimum of three years, with the studies to cover real-world operating conditions, including severe weather. Under the initial phase of the $14 million research program, Siemens contributed $9 million, with $5 million from NREL. On August 20, NREL began installation of a 1.5-megawatt Department of Energy (DOE) turbine manufactured by General Electric, in addition to the 2.3-megawatt turbine from Siemens.

NREL estimates that the 428-ft (131m) Siemens turbine could supply enough energy to power 630 homes, while the 389-ft (119m) GE system could supply energy to 410 homes.

To the west of the Siemens turbine, a new meteorological tower features more than 60 instruments to collect data on wind, temperature, dew point, precipitation, and other environmental variables that can influence the turbines’ performance and lifespan. The Dept. Of Energy and local utility supplier, Xcel Energy, are negotiating an agreement for surplus energy to be sold to the local utility grid. Siemens has also decided to locate its wind-power research and development center in nearby Boulder, with that office expected to grow to a staff of 40 by 2013.

Siemens blades are produced at a range of facilities, including an Aalborg, Denmark site that employs 3200, and a rotor-blade factory in Fort Madison, IA that opened in September 2007. In the Danish site’s “blade baking” production hall, which is 250m long, large molds are used to form components that measure over 50m in length and weigh up to 16 tonnes.

With a typical service life of 20 years, Siemens says the rotors are constructed from fiberglass that’s injected with epoxy resin and baked, resulting in a fiber-reinforced plastic composite. Siemens says its blades, unlike some rivals' products, don’t contain any polyvinyl chloride (PVC). In production, a mold is initially lined with multiple layers of fiberglass prior to injection of the epoxy. Siemens says there are 7 tonnes in a 45m blade, and 12 tonnes in a 52m blade. To enhance stiffness, a layer of wood is placed between the fiberglass layers. Utilizing the company’s production methods, it takes 48 hours from the first step to a completed blade, instead of several days, with one day to position the fiberglass and a second day to inject and bake.

On March 25, GE and Siemens competitor Vestas celebrated the ground-breaking for two manufacturing facilities also located in Colorado, starting construction of nacelle assembly and blade factories in Brighton. Once the factories are fully operational in 2010, they will create about 1350 jobs and represent a total investment of $300 million, with annual production capacity for 2000 blades and 1400 nacelles.
 
In 2008, the American Wind Energy Assn. (AWEA) reported that the U.S. broke all previous wind-energy activity records by investing $17 billion to install 8358 megawatts of new wind capacity. Vestas currently has a workforce exceeding 1800 in the U.S. and Canada, with that number expected to grow to 4000 U.S. workers by the end of 2010. In addition to the two factories in Brighton and the existing blade factory further north in Windsor, CO, Vestas is constructing what it calls the world’s largest tower factory in Pueblo, CO, with that facility set to open by the end of 2009.
 
More recently, on Oct. 15, Vestas officially inaugurated its largest wind-energy manufacturing complex in China’s Tianjin Economic Development Area. The site, which has 130,000m² of factory space, added production of control systems and machined parts, while expanding capacity of the existing generator and blades factories.

In a release, the company said these new facilities will not only lift Vestas’ production capacity, but also continue its efforts to increasingly localize production, with the goal being 100% China-sourced supply. The company invested more than RMB 1.8 billion (over $220 million) in the new capacity, after already spending more than RMB 2.5 billion ($380 million) in Tianjin, with plans to invest more than RMB 3 billion in China by the end of 2009. The company came to Tianjin in 2005, and in addition to its manufacturing complex there, Vestas has regional headquarters in Beijing, a new factory in Hohhot, a procurement office in Shanghai, and is currently constructing additional facilities in Xuzhou. By the end of 2009, it will have 3000 employees in country. Vestas, which began to concentrate exclusively on wind energy in 1987, claims a 23% global market share. The company has installed more than 38,000 wind turbines in 63 countries, with more than 10,000 on American soil. —Tony Deligio