Maxwell Technologies Inc. reported that sales of BOOSTCAP ultracapacitor products for wind energy applications through the first three quarters of 2010 are running more than 40% ahead of wind-related sales in the same period last year, and estimates that more than 13,000 BOOSTCAP-equipped turbines are now in operation worldwide.
Maxwell now is supplying BOOSTCAP cells and multi-cell modules to several wind energy system integrators and turbine OEMs in Europe, Asia and North America. Ultracapacitors provide burst power for electrical blade pitch control systems that enhance the consistency of wind turbines’ electrical energy output and ensure that rotor speed remains within a safe operating range by constantly adjusting turbine blades to compensate for changes in wind velocity. Ultracapacitors also provide an independent source of backup power for orderly shutdown in the event of a main system power failure and are used to smooth the flow of wind farms’ output to the electric utility grid.
An estimated 60% of newly produced wind turbines employ electrical blade pitch systems that incorporate ultracapacitors or batteries for pitch control and backup power, according to Maxwell. The remainder employ hydraulic systems that do not require ultracapacitors or batteries. Ultracapacitors have been designed into an increasing share of the electric pitch system portion of the market because of their longer operating lifetime, low maintenance requirements and superior cold weather performance compared with batteries.
Industry sources report that approximately 38 gigawatts of new wind generator capacity was installed in 2009, bringing the total worldwide installed base to nearly 160 gigawatts. From 2005 through 2009, the industry maintained an annual growth rate of more than 30%, and it is projected to continue growing strongly through the balance of the decade.