Germany - Nordex takes on N90 wind turbine blade production

Germany's wind turbine powerhouse Nordex is bringing blade production for one of their top wind turbines in-house. After the completion of intensive testing, the company is beginning the internal production of rotor blades for its N90 2,300 kW turbine. The N90 blades are amongst the largest currently being produced in serial form. With a length of around 45 meters, an NR 45 blade is roughly as long as the wing span of an airliner such as the Airbus A300. In fact, the sweep of the rotor has the same dimensions as a football field (6,362 square meters). Yet, size is not a purpose unto itself.

"Many sites in Europe can be utilized more efficiently with our N90 than with conventional turbines," said Thomas Richterich, spokesman for Nordex AG's Management Board. This is why demand for this series has risen sharply over the past few months." Roughly 61 percent of the projects which Nordex is planning for this year are based on the N90, with the company expecting a similar proportion in new orders.To date, Nordex has sourced its N90 blades solely from a Danish supplier. "We now want to reduce this dependence to improve our earnings situation and to stand apart from the competition to an even greater extent," Richterich said.

To achieve this, Nordex has developed a new blade design. Thus, the load-bearing structure is separate from the aerodynamic cover to optimize the blade properties. This differential construction method is also used in the aircraft industry. The main advantage is the low weight of the blade, something which has a positive effect on operating loads and thus the availability of the system as a whole. Nordex says the production method is also innovative. The vacuum injection method tested with smaller components over the past two years is now being used for all components of the NR 45. This method involves placing the glass fiber in a vacuum so that the structures can absorb the resin. In addition, Nordex is employing a new coating method which has proven to be highly weather-resistant in practice. For this purpose, only polyurethane is used as a basis.

Yet, there is another reason why the NR 45 is a welcome change for the roughly 80 employees at Nordex's Rostock plant. To date, Nordex has been solely producing rotor blades for the two 1.5 MW turbines at this facility. On account of muted demand in Germany, however, the company expects sales of the rotor blades for this series to weaken in the medium term. Accordingly, the new of production of the blades for Nordex's top-selling N90 has come at just the right time, said the company.