A wave power apparatus includes at least one rotationally supported arm (122) which carries a float (124) at its free end, so that a translational movement of the float caused by a wave results in rotation of the arm (122). The apparatus comprises power conversion means for converting power transmitted from the wave to the arms into electric power, e.g. a hydraulic system, in which a hydraulic medium is displaced by the movement of the arm, the hydraulic system being coupled to an electric generator. The apparatus comprises a hydraulic lifting system for lifting the float out of the ocean and for locking the float in an upper position above the ocean surface, e.g. during extreme sea wave conditions, such as storm. The lifting system may comprise at least one pump for pumping hydraulic cylinders for lifting the arm out of the ocean.