Size Counts: Siemens' 154-Meter Quantum Wind Turbine to Produce Greener Power

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Written by Richard Finlayson, Senior International Editor for Industrial Info Resources (Sugar Land, Texas)--The American Chemical Society (ACS) journal, "Environmental Science & Technology," recently raised the prospect of super-giant wind-turbine blades approaching 1,000 feet (305 meters) in rotor diameter. A scientific study showed that bigger turbines produce greener electricity.

The two main reasons for this are that manufacturers now have the knowledge, experience and technology to build big wind turbines with great efficiency. Advanced materials and designs permit the efficient construction of large turbine blades that harness more wind without proportional increases in their mass, or the mass of the towers and nacelles that house the generators. This means more clean power without large increases in the amount of materials for construction or fuel for transportation.

One study shows that the average size of commercial turbines has grown 10-fold in the last 30 years, from diameters of 16.5 meters in 1980 to nearly 160 meters today.

Illustrating this trend, Siemens AG (NYSE:SI) (Munich, Germany) has just produced the first batch of its new 75-meter-long B75 rotor blades to be installed on a Siemens 6-megawatt (MW) offshore wind turbine. The total rotor diameter will be 154 meters, with a swept area of 18,600 square meters.

Siemens claims that the B75 Quantum blade demonstrates tremendous strength at low weight and, thanks to unique airfoils, offers superior performance at a wide range of wind speeds. Using traditional technology, the B75 blades would be 25% to 50% heavier. Heavy blades are subject to higher loads and require stronger nacelles, towers and foundations.

The B75 is the world's largest fiberglass component to be cast in one piece, and the mold consists of two parts to allow for transportation.

The company's SWT-60 units can use rotors of 120 and 154 meters in diameter and feature a direct drive mechanism, which lowers operation and maintenance costs. Siemens claims that the tower head mass of 350 tons is the lightest in its class. The nacelle features a helicopter-hoisting platform.

The first commercial wind turbine operating at 10-meter-per-second wind speed had a 30-kilowatt capacity turbine. The B75 extracts energy from 200 tons of air per second when operating in winds of 10 meters per second.

Industrial Info Resources (IIR), with global headquarters in Sugar Land, Texas, and eight offices outside of North America, is the leading provider of global market intelligence specializing in the industrial process, heavy manufacturing and energy markets. Industrial Info's quality-assurance philosophy, the Living Forward Reporting Principle™, provides up-to-the-minute intelligence on what's happening now, while constantly keeping track of future opportunities.