The photo is sourced from worldwidewind.no
Most modern wind turbines have a horizontal axis, i.e. the rotor drive shaft (the rotating part of a turbogenerator), which is fitted horizontally relative to the ground, and the turbine’s heavy components (its blades, transmissions, gearboxes) fixed to the tower top. The capacity of horizontal wind turbines is highly dependent on the blade length, which makes almost impossible the use of the blades in offshore deep waters. As an alternative, World Wide Wind has suggested vertical-axis wind turbines having a lower gravity center because their heavy components (except for the blades) are located closer to the base.
The World Wide Wind development is distinguished by simple design: the upper turbine is connected to the rotor located at the wind turbine base, and the lower one – to the wind generator stator. As noted above, the contra-rotating blades will allow the power plant to capture wind energy from any direction. Once submerged in water, the structure may take tilt of about 60 degrees, but remains stable.
In case of successful testing and commercializing, the World Wide Wind innovation will add to the range of vertical wind turbines that will be particularly in demand in the Baltic and North Seas, a key European hub for offshore wind energy. Earlier, the Swedish SeaTwirl created a floating wind turbine prototype, the above-water part of which consists of a static shell and a rotating tower which is fastened with the struts and the rotor blades, and the underwater part is made of a float on the tip of which there is a jacket with a fixed ballast. SeaTwirl plans to launch commercial production of such power plants in 2025.