The Pendulum WEC consists of a rectangular raft anchored to be aligned with its longitudinal direction parallel to the wave fronts. The waves will give the raft a rolling motion powered by the energy from the long wavefront along the length of the raft. There is a deep transverse keel below the raft with a double turbine fixed horizontally along its lower end, with one rotor on each side of the keel. The rolling motion of the raft results in the turbine being driven through the water in a back-and-forth pendulum movement. Each of the two counterrotating rotors rotates in the same direction due to Waveco’s innovative turbine blade construction. Shafts and gear, couple the rotors to an electrical generator in the raft. The Pendulum WEC will have a natural pendulum frequency determined by the height of the centre of gravity above the centre of buoyancy. If the natural frequency does not match the frequency of the waves, the transfer of energy from the wave to the raft will be inefficient. Therefore, the raft has a tower with a water tank on top. The amount of water in the tank will shift the centre of gravity and thus the natural frequency. A computer will constantly compare the amount of water in the tank with the energy output from the converter’s generator and seek to maximize the output. The system will enhance energy capture from the low waves that dominate the wave spectrum in most coastal waters in the world.