Energy yield calculations of a wind turbine with tethered blades

It does this by employing a very direct way of transmitting the thrust and circumferential forces from the blades to the base. Aerodynamically, the concept is as close as possible to a horizontal axis wind turbine (HAWT). On a mechanical level, utmost care has been taken to restrict the sub-technologies to those that are already industrially available in the energy sector, ensuring good availability and reducing development risks. As an implication of its direct force management principle (carrying the aerodynamic forces as tension instead of bending), a Tiira turbine produces only very limited bending moments at its base and has a low centre of gravity. It thus lends itself particularly for floating applications and promises to provide competitive renewable energy from deeper-water offshore sites. The tremendous growth potential from these floating offshore sites can so far not be harvested in an economically viable way, as indicated by the fact that large players have been re-selling their floating wind leases in recent years. Tiira promises to be a thoroughly conceptualised and robustly engineered solution to open up the wind resources in deeper water.

In this project, OST will develop a free vortex model to predict the behaviour of Tiira turbine. This includes answering the questions “How well do the model’s predictions match with the power output of known systems like HAWT?”,  “What power output does the free vortex model predict for the Tiira system at different wind speeds?” and “How effective at pushing scaling barriers is our proprietary method for balancing gravity induced fluctuations of the blades’ potential energy?”