The two major gearbox suppliers are German Winergy, which has about 50% of the world market, and Hansen of Belgium, with approximately 30% of the market. While Winergy supplies to a wide range of wind turbine manufacturers (table), Hansen only serves Vestas and Gamesa, two former technology partners before their split in 2001.
Winergy is a separate business unit of Flender, a major supplier of mechanical and electrical drives, which was bought by Siemens earlier this year. At the time of the purchase, Flender had 6700 employees and an annual turnover of EUR 1.012 billion. It was bought by Siemens for EUR 1.2 billion (Windpower Monthly, May 2005). The purchase was controversial among wind turbine manufacturers, most of whom now find themselves reliant on gearboxes supplied by a subsidiary of a company they are in direct competition with -- the wind unit of Siemens Power Generation. Flender has supplied the wind industry with gearboxes since at least the early 1990s, including to NEG Micon, which suffered a major series failure of gearboxes in the late 1990s.
Hansen Transmissions of Belgium was also recently bought by a much larger company, the German Allianz insurance group (Windpower Monthly, November 2004). Allianz already had insurance interests in the wind business before its purchase of Hansen 18 months ago from debt ridden Invensys plc of the UK. Hansen had reportedly been for sale since 2001. It has supplied gearboxes for wind turbines since the early 1980s.
One of the oldest gearbox suppliers to the wind industry is Moventas of Finland, formerly known as Metso. The gearbox brand recently went through its fourth name change when Metso Corporation sold Metso Drives to Scandinavian equity investment group CapMan and the name was changed to Moventas.
Moventas sells gearboxes exclusively to Metso. Metso was owner of Valmet Power Transmission, which has supplied gearboxes to the wind industry since the early 1980s, starting with 55 kW machines. Valmet merged with Santasalo Gears Oy in late 2002 and for a period the name Santasalo was also used as a brand name.
Valmet gearboxes in wind turbines suffered widespread failure in the 1990s and a retrofit was carried out of 880 Valmet gear units in Vestas turbines. Valmet units have been supplied to Vestas, NEG Micon and Gamesa.
Two further gearbox companies supplying to the wind industry are Germany's Bosch Rexroth, a large drive and control equipment company with international interests. It has linked up with GE Energy's wind unit, among others. Another German company, Eickhoff, which describes itself as a world leader in design and manufacturing of high performance gearing products, supplies to Germany's Nordex, GE Energy and Repower, says the company's Karsten Sikora.
A company that appears to be struggling in the wind industry is Jahnel-Kestermann, a family owned German firm up until its purchase by French investment company Arques Industries in April earlier this year. Jahnel-Kestermann, which considers itself the smallest of the six main gearbox suppliers, was a one time supplier to NEG Micon. It is now in dispute with Vestas over failures in NEG Micon wind turbines (see separate story) and while Vestas Denmark is refusing to do business with Jahnel-Kestermann, its Indian division remains a major customer.
Other gearbox brands with business in the wind industry include Germany's Lohman & Stolterfoht (now a division of Bosch Rexroth), Pujol, which supplies Spain's Ecotècnia, and Echesa, owned by Gamesa.
Just as wind turbine manufacturers use multiple gearbox suppliers, gearbox manufacturers utilise several bearing partners. The major supplier of bearings to the wind industry -- with about 50% of the market -- is Swedish company SKF, the world's largest bearing manufacturer. Next come the INA/FAG brands from Germany, while Timken, the largest bearing manufacturing company in the United States, comes in a distant third.
In Europe, SKF is the leading bearing company, closely followed by Germany's Schaeffler Group, which is the holding company for INA and FAG, two large bearing firms. SKF is number two in North America, behind Timken. In Asia, SKF is the number one bearing supplier excluding Japan, where several Japanese bearing companies dominate the market. Of these, NTN supplies bearings to Mitsubishi turbines.
SKF was one of the early wind industry pioneers, dating back to 1981. Within SKF, though, wind is a small percentage of total revenues. "Compared to the overall business of SKF, wind is a small part," says Werner Goebel, senior business engineer at SKF. "But wind is a very attractive area to us due to fantastic growth rates and its requirement of innovation."