The Areva Multibrid M5000-135 explained

FRANCE: At EWEA Offshore 2011, Areva Wind presented an upgraded version of its M5000 turbine with an enlarged 135-metre rotor. The previous version, which launched seven years ago, had a 116-metre rotor.

The M5000 concept was originally launched in 1997

According to chief technology officer Rene Balle the turbine offers 8% extra annual yield at 9m/s average wind speed at sites similar to those along the French coast.

A prototype is planned for Q2-1013 with series production start expected in the second half of 2014.

Besides longer and slender rotor blades, Areva added several additional design features like a new nacelle design aimed at easier assembly, improved serviceability, and enhanced health and safety performance.

The M5000 is a patented turbine concept, which was first introduced in 1997 by German engineering consultancy Aerodyn.

It is characterised by a fully integrated drive system comprising a single-stage planetary gearbox and a low-speed permanent magnet generator, incorporated in a single cast load carrying structure.

The turbine was one of the first turbines with journal bearings in the gearbox, known for their compactness and long lifetime, high-load bearing capability and resistance to impact loads.

"Mechanically the M5000-135 gearbox has been left unchanged and the loads-reducing rotor blade has kept turbine loads at a similar level by retaining the same high safety margins," Balle concludes.