ROTOR BLADES WITH STRAW
Straw may play an important part in the construction of wind turbine rotor blades, according to the Fraunhofer Institute for Wood Research. In a research project headed by engineer Frank Moeller, the objective was to find "an environmentally compatible alternative to the plastic and metal sandwich constructions in widespread use today." The result was a new composition: a sandwich of natural materials where the outer surfaces are made of domestic woods while the core consists of stocks such as straw, bonded together with a glue of gluten foam. "The resulting product is remarkably lightweight and highly durable," claims Moeller. "The new technology has a wide range of potential applications from car bodies and sports equipment to wind turbine blades." However, there is a catch. "For widespread use realistic price levels must be achieved," he says. The next step in the project will be to optimise methods of cultivating cereals and develop economic means of simultaneously harvesting corn and processing straw. Immediate plans foresee the construction of a pilot plant with a daily output of 150 cubic metres of the straw-based composite material.