An ocean power turbine for converting a slow water flow energy comprising - at least one endless rotation chain having a plurality of plate holders arranged in the rotation chain, each plate holder comprising at least one plate attached in each plate holder, where said rotating chain runs in an extended path around and engages with at least one drive wheel in the one end arch of the path by means of at least one engagement device (22, 22u, 221, 22f, 22r) - further each plate is pivotably attached to the plate holder to switch between the open position with the primary flow direction of the water flow and closed position towards the flow direction, and - the drive wheel has a turbine shaft coupled to a generator device for utilizing the rotational energy, further the path of the rotation chain slanted relative to the main flow direction of the flow of water, all arranged in a fully or partially submersible support structure, - wherein the number of rotation chains comprising plate holders and plates are two, and oppositely arranged in a plow formation and - the support structure comprises a partition wall arranged along the path of a web inside the path of the rotation chain in the full height of the plates characterized in that - the support structure is subdivided into a top section and a bottom section respectively above and below an operating structure comprising at least said rotation chains, said plate holders, said drive wheel and said turbine shafts and the outer walls of the top section and bottom section have a sloping, at least lower wall portion, towards said operating structure comprising at least said rotation chains, said plate holders, said drive wheel and said turbine shafts, and together with the partition wall forming a lateral concave duct for guiding the water towards the plates and increase the water current in the slow water flow and thus the power to the plates and further the effect to the turbine. - at least one endless rotation chain having a plurality of plate holders arranged in the rotation chain, each plate holder comprising at least one plate attached in each plate holder, where said rotating chain runs in an extended path around and engages with at least one drive wheel in the one end arch of the path by means of at least one engagement device (22, 22u, 221, 22f, 22r) - further each plate is pivotably attached to the plate holder to switch between the open position with the primary flow direction of the water flow and closed position towards the flow direction, and - the drive wheel has a turbine shaft coupled to a generator device for utilizing the rotational energy, further the path of the rotation chain slanted relative to the main flow direction of the flow of water, all arranged in a fully or partially submersible support structure, - wherein the number of rotation chains comprising plate holders and plates are two, and oppositely arranged in a plow formation and - the support structure comprises a partition wall arranged along the path of a web inside the path of the rotation chain in the full height of the plates characterized in that - the support structure is subdivided into a top section and a bottom section respectively above and below an operating structure comprising at least said rotation chains, said plate holders, said drive wheel and said turbine shafts and the outer walls of the top section and bottom section have a sloping, at least lower wall portion, towards said operating structure comprising at least said rotation chains, said plate holders, said drive wheel and said turbine shafts, and together with the partition wall forming a lateral concave duct for guiding the water towards the plates and increase the water current in the slow water flow and thus the power to the plates and further the effect to the turbine.