The XD137 4MW is based on the company's existing offshore turbine the XD115 5MW, but modified for lower wind conditions.
Darwind engineer Oziel Garcia Jaimes told Windpower Monthly: "The rotational speed of the new turbine will be lower, so the torque will be different and the generator will have to be developed accordingly, but it will essentially be based on the 5MW generator."
Changes have been made to the cooling system, with the new design likely to include a passive system made up of laminates on the outside of the generator. This is expected to replace the pumped cooling system evident in the external pipes extending from the 5MW turbine.
However, the turbine is currently being designed, and Garcia Jaimes stressed that this has not been finalised. Darwind expects the prototype to be erected towards the end of 2015 and said that it would be ready to go into serial production shortly after that.
Europe will be the key market for the turbine.
XEMC Darwind announced plans to enter the European onshore wind market in 2013 with a 4.5MW and a 5MW direct-drive turbine, also based on the company's 5MW offshore model. Both are aimed at high-wind sites.