Submersible plant comprising buoyant tether

Method for control of a submersible power plant, wherein the method comprises:

• arranging a tether connecting a submersible power plant with a structure, wherein the tether comprises an upper tether part and a lower tether part;
• arranging the upper tether part to have an average density higher than the surrounding fluid;
• arranging the upper tether part to have a hydrodynamic cross section;
• arranging the upper tether part to be connected to the vehicle;
• arranging the lower tether part to have an average density lower than the surrounding fluid;
• arranging the lower tether part to have a non-hydrodynamic cross section;
• and
• arranging the lower tether part to be connected to the structure,
• wherein when the submersible power plant moves in a predetermined trajectory, the tether of the submersible power plant experiences a reduction in tether vibrations induced by whiplash, and
• wherein when the submersible plant does not move in a predetermined trajectory, the tether of the submersible power plant forms an S-shape due to the difference in average density between a vehicle of the power plant, the upper tether part and the lower tether part.