The foundation is a structural element that transmits stresses imposed by the tower and all other items of equipment to the ground. It is composed by a block and stakes, which supports the tubular tower and is dimensioned according to the height and loads that it will receive. In this regard, the project for the foundation of a wind turbine is very important because it is affected by the overturning moment of the tower in extreme wind conditions.
Bearing in mind the importance of the foundation throughout the construction of the wind tower, Energiekontor, the company responsible for the project of the RBE – Rotor Blade Extension, has conducted studies and inspections in order to verify whether the installation of the blade extension affects the tower foundation.
The RBE brings many advantages, including the possibility of increasing the wind farm’s Annual Energy Production without replacing the rotor blades or the wind turbines.
In summary, the main advantages of the Rotor Blade Extension consist in:
- Production increase – 3-year payback period
- Patenting by Energiekontor – Certified by DEWI-OCC GmbH
- Installation on hanging blade – Short downtime period during installation
- Low environmental impact – The RBE installation uses existing infrastructure. Thus, the environment and the surrounding area suffer much less impacts.
Besides increasing wind turbine efficiency, the RBE project has many other advantages. Some questions about the installation of rotor blade extensions have been raised, such as whether it can affect the structure of the wind tower, putting the safety and the tower operation at risk. EnergieKontor, the company responsible for this project, has conducted some studies, inspections and monitoring reports, which proved that the foundation does not go through significant effects.
Since the maximum achieved rotor thrust is maintained, given the decrease in the turbine cut-out wind speed, the maximum bending force on the foundation is also maintained within safe operating parameters. In addition, a real life measurement of the natural frequencies of the turbine was performed to understand the functional security of the turbine. According to the subsequent report, “the modifications produced by blade extension did not significantly alter the dynamic behaviour of the wind turbine rotor and tower”.
Specific reports indicate that the foundation statics remain unchanged, due to:
- Unmodified rated power status;
- Equal rotor thrust compared to the original design;
- Small blade mass increase does not affect strain loads.
If you have any doubts about how to install a RBE in your wind farm to increase its productivity, feel free to email us to energiekontor@rotorbladeextension.com or call us, and talk directly with us for more information.
