Abstract: The invention involves a device for utilizing the energy from sea swells and waves. The device is characterized by the combination of:(a) a vessel adapted to follow the regular undulations of sea swells at a place of anchorage, and constructed in a manner to face the swells so as to pitch and not to roll while anchored;(b) air cylinders disposed at least at one extremity of the vessel to moderate more or less the amplitude of the pitching;(c) watertight compartments containing a liquid;(d) prime movers, such as continuously powered turbines, located in the path of the liquid and suited to harness energy from the liquid as it moves so as to supply mechanical energy to at least one rotatable shaft; and(e) liquid deflectors located at the extremities of each water-tight compartment.