Generating electrical power from tidal streams can present the turbine designer with some unique challenges. These can include: very high axial thrust, large variation in water velocity across the diameter of the rotor and highly turbulent flow. Real time, accurate information of the in-service loads is therefore of great importance both for optimising design, quantifying fatigue loading of blades and bearings, and for long-term structural health monitoring. The combination of high fatigue loading and sub-sea operation means that fibre-optic sensing is probably the only technology capable of providing cost effective and reliable long term strain monitoring in this type of application.
Craig Love of Andritz Hydro Hammerfest commented:
"We have been delighted with the performance of the fibre strain monitoring system provided by Epsilon Optics. The system operated flawlessly for the entirety of the 3.5 years our prototype turbine was deployed. We were particularly impressed by the robustness of the fibre and connector design in what is an extreme environment combining seawater and rotation with no opportunity for unplanned maintenance."