Demonstration of Commercially Viable Megawatt-Scale Adaptive Blade Technology

70880S02-II The cost of wind energy has declined dramatically in the past 20 years and is now closely competitive with more conventional sources of electrical energy. This project addresses the need to further reduce the cost of wind energy, by developing an innovative rotor design for commercially available, megawatt-scale wind turbines. In order to reduce loads without increasing system costs, an adaptive blade will be designed to change pitch (twist) at the same time it bends in response to changes in wind speed. This will be accomplished by making optimal use of carbon fiber. Phase I examined a matrix of possible blade designs and identified several that offer significant energy reductions. The study included updated and current carbon-fiber-material properties, manufacturing methods, and cost information to ensure that an optimized design can deliver at least a roughly 5% energy reduction. Phase II will design, build, and test a megawatt-scale (30 m) blade that uses bend-twist coupling to reduce loads without increasing overall costs. Commercial Applications and Other Benefits as described by awardee: The potential market for blades of this type is over $500 million annually at today¿s level of wind turbine sales. The technology also should facilitate commercial acceptance of carbon fiber in wind turbine blades.