Wind turbines have grown in size throughout the last decade from several hundreds of kW to several MW’s, the large majority being of the classic three-bladed upwind configuration. However for off-shore installations and off-grid systems reliability, robustness and ease of installation are important design drivers that lead to different technological concepts. Under these circumstances a lightweight flexible turbine can provide electricity at lower cost than the classic turbine concept. One key element of this concept is a rotor with a high degree of bend-twist coupling effectively shedding loads at high windspeeds and passively controlling peak power and rotor speed by large deformations of the rotor blades. Design tools and especially aero-elastic simulators have been conceived with different wind turbine configurations in mind and as such claim to be compatible with any design concept. The industry has provided ample opportunities for the research institutes and engineering consultancies to calibrate and validate their design software for the classic concept of the 3-bladed upwind turbine. Very few projects however have made it possible to fine-tune the design tools for turbines incorporating a high degree of flexibility in rotor blades. This project will deliver proof-of-concept of a wind turbine rotor that uses aero-elastic tailoring techniques as a passive means of controlling the power and speed of the turbine. The analysis of the appropriate structural lay-out and the right choice of materials are among the key research elements of this project. Additionally the project will provide a platform to validate a state-of-the-art aeroelastic design tool and CFD code by using them throughout the design process of the flexible rotor and afterwards compare the predicted behaviour of the rotor with windtunnel test results on a scale model. Finally, knowledge will be gained on the testing procedures for flexible rotors in a rotating test configuration.