LM Wind Power to develop wind turbine blade with flexible tip lengths.

LM Wind Power has announced the launch of a project to develop wind turbine blades with flexible tip lengths which have the potential to reduce cost of energy by 8-10%.

The four-year project, led by Danish wind turbine blade manufacturer LM, is supported by the Dutch Ministry of Economic Affairs. It brings together a consortium of partners which includes the Dutch University of Twente and the Energy Research Centre of the Netherlands (ECN).

The energy output of a wind turbine depends on its location in the wind farm as each turbine is subject to different wind conditions (often due to wake effects), explains LM. This means many of the turbines running today are not loaded to their full capacity as typically the turbines installed in the farm are of similar design regardless of their position in the array.

This project will aim to optimise individual wind turbines to their maximum performance by extending the rotor diameter with variable tip lengths.

The blade concept is based on a standard blade part with variable tip lengths. LM says it builds on an existing composite blade design, but uses an assembly process which leads to a permanent assembly of the two blade parts, adding minimal weight.

The result is a larger rotor blade that increases annual energy production significantly for a relatively small investment.

The flexible tips are expected to be manufactured separately, which enables the use of specific techniques and a one-shot manufacturing technology while providing economies of scale. Assembly is expected to be done on or near site.

The project consortium believes offshore wind will benefit most from the concept as the improved performance resulting from the blade length optimisation will see a quicker pay-back at sea.

The new rotor blade will be a universal solution that can be adapted to various turbines and applied in every wind farm.