Direct Drive Wind Turbines
By Mark Norfolk on Thursday, April 1st, 2010
Late last year, EWI led a team of Ohio organizations to bid on a US Department of Energy grant to build a large scale wind turbine drive train testing facility. The general principal of the Governments RFP was that wind turbines are getting larger and larger. As size increases, the torque driven through the turbines gearbox grows past the limits of current gearbox technology. The grant was designed to encourage the development of a test lab with equipment large enough to test new designs up to 15MW. To give you a perspective, the test equipment that the Ohio team spec’d out is larger than the gearboxes used on nuclear air craft carriers!
In the end, the DOE awarded the grant to a consortium from South Carolina, thereby concluding a 400 hour chapter of my life. Interestingly, it appears as if GE is taking a different approach to the same problem through the acquisition of ScanWind. This company has been developing turbines that are direct drive, meaning there is no gearbox. With fewer moving parts this has the promise of increasing reliability, which is vital for turbines located off shore. It will be interesting to see in ten years whether industry supersizes current gearboxes or whether they successfully implement direct drive