This paper reports the performance of a tidal turbine station keeping system based on the adoption of a tensioned mooring system in different sea states. The capabilities of introducing damp are being investigated to reduce the peak loads that tidal turbine experienced during their operational life in high energy wave-current environments and extreme sea states. The loading on the turbine rotor blades and buoy are calculated using a wave and current coupled BEMT. The modeling algorithm developed is based on an inverted triple pendulum, responding to different sea state conditions to understand the system response behavior and the blades loading in different sea states, including the extreme conditions. The results show that the tensioned mooring system reduces peak thrust loading on the turbine, but it was found that there are certain limitation when using this design in extreme waves conditions.