Improving wind farm output through smart blade tips
Much more offshore wind power plants. That’s the future of wind energy. It means that today’s challenge for the industry is to design efficient wind farms instead of solitary turbines. ECN and LM Wind Power are working on innovative blade tips to improve offshore wind park yields. The results are impressive.
“The design of an offshore turbine blade requires a different way of thinking for two reasons”, says Ozlem Ceyhan-Yilmaz of ECN. “Firstly, there are fewer limitations to noise emission because there are no people living nearby. Secondly, the offshore challenge is to design rotors that will result in the largest power output for complete wind farms.”
Different types of blade tips
To influence the wake behind the turbine, ECN and LM Wind Power designed a special tip. With the new tips, the power production will increase by two to six percent:
- A tip specifically designed for offshore conditions: designed for integral optimisation of turbines without considering noise limitations.
- An innovative wake reduction tip, invented by ECN: the zigzag shape increases turbulence in the boundary of the wake which increases the yield of offshore wind farms.
Full scale experiment Wieringermeer
These designs were validated on 2.5MW-sized wind turbines at ECN’s wind turbine test facility in the Wieringermeer. Ozlem: “This demonstration was unique. A full-scale experiment in an operating wind farm was performed. Then tips were installed on the blades of the wind turbines in such manner that they could be removed afterwards. The method for installation and removal has been an innovation by itself, and required close cooperation between ECN and LM Wind Power.
The results of the test at these 80m large rotor blades demonstrated that an increased farm power output up to six percent is achievable through blade tips. By using a new method, ECN made it possible to measure relatively small power increases. Ozlem: “Great results are encouraging to continue designing models and demonstrating blade tips. Together we aim to lower costs of wind energy.”
More information and contact
For more information on the work of ECN on rotor blades, please contact Peter Eecen or Glen Donnelly via our contact form.