Abstract: The invention pertains to energy production by capturing simultaneously water potential (surface height differences due to waves) and kinetic (flow of water due to e.g. waves, tide or streams) energy. The plant can have tidal compensation (2, 3, 22, 23) to avoid energy flux streaming over the plant in high tide, and directional stabilizing arrangement to turn it automatically parallel to wave crests. Surfaces capturing energy from flow have optimized movements to follow speed of water in different depths. Also energy conservation to filter output ripple can be arranged with twin-phase fluid accumulators (51, 55).

Abstract: The invention pertains to underwater energy plants utilizing water movement due to e.g. waves, tide or stream. The invention also relates to parts of such a plant, namely an underwater wing for capturing wave energy, apparatus to convert the mechanical energy to electrical energy, and a connector for transferring the electrical energy. In certain embodiments of the invention, a wing causes a moment around hinging axis due to water flow with autonomous or tethered in-hinge electric generator and underwater attachable high power electric connector based on inductive transfer of energy.