Windturbines zijn duurzamer met metalen rotorbladen
4 mei 2015 – Windturbines zijn duurzamer met stalen rotorbladen dan met de glasvezelversterkte plastics waarvan ze vaak worden gemaakt. Metaal is beter te hergebruiken en goedkoper, aldus het Duitse onderzoeksinstituut Fraunhofer.
Uit een bericht van Fraunhofer
‘(…) Wind turbines feed eco-friendly power into the grid. To keep their weight down, the majority of larger rotor blades are made from fiber-reinforced plastics. These materials are rarely recycled at present, in part because it is very complicated to do so. Researchers at the Fraunhofer Institute for Machine Tools and Forming Technology IWU in Chemnitz are therefore focusing on metal, and especially steel, as a blade material. In smaller installations, the greater weight of the steel blades is inconsequential; as in-
stallations get larger, light alloys can be used to keep blade weight down. Collaborating with colleagues from the Free University Brussels (VUB) in the HyBlade project, Fraunhofer IWU is developing the required aerodynamics as well as the necessary manufacturing process chains. Manufacturing steel blades offers numerous advantages. “First, it makes turbines significantly more ecological, since more than 90 percent of the steel can be recycled – so using metal rotor blades makes wind power truly environmentally friendly,” explains Marco Pröhl, a researcher at the IWU. “What’s more, compared to similar blades made of fiber-reinforced plastic, the cost of rotor blade mass production drops by as much as 90 percent – and the blades can be manufactured more accurately.” (…)’
Bovendien zijn stalen bladen makkelijker te produceren, menen de onderzoekers. Bij de glasvezelversterkte kunststof bladen komt nogal wat handwerk kijken; de metalen bladen kunnen makkelijker in serie geproduceerd worden.
‘(…) The researchers have already produced a blade 15 centimeters wide and 30 centimeters long, using it to optimize the individual processing steps. Their next step will be to produce an entire rotor for a vertical axis turbine with 2.8-meter-long blades and a diameter of two meters. Once it is installed at a test site for small wind turbines on the Belgian coast, it will be put through its paces. (…)’
Fraunhofer, 4 mei 2015: Generating eco-friendly power with metal rotor blades