Flexible tidal turbine blades reduce fatigue loads in model tests

Researchers demonstrated flexible rubber tidal turbine blades that reduced fatigue-inducing load fluctuations by up to one-third while matching the energy yield of rigid blades with active pitch control over simulated tidal cycles, in a study published in Nature. The blades retain a rigid front section while their flexible trailing edges flatten under load, regulating forces without hinges, bearings or actuators. Tests took place at the University of Edinburgh's FloWave facility. The results establish a passive alternative to mechanically adjusting blade angles, but come from model-scale tests. The flexible blades also produced higher thrust coefficients at lower, off-design velocities, where absolute forces were smaller.