Hydrokinetic energy conversion system and use thereof

A hydrokinetic energy conversion system comprising a turbine device comprising a rotor displaying a rotational axis, which turbine device is arranged to operate with the rotational axis in an inclined orientation vis-à-vis an incoming body of water, and which rotor comprises at least one helical blade which is arranged to interact with the incoming body of water such that rotational energy is imparted to the rotor, which at least one helical blade comprises a first, convex surface, a second, concave surface and a free, distal edge where the first surface and the second surface meet, wherein the curvature of the second surface, when viewed in a plane orthogonal to the rotational axis, is such that a maximum depth of the second surface, when measured from a straight line intersecting the rotational axis and the distal edge, is at least 35% of the distance between the rotational axis and the distal edge and in that the at least one helical blade, at the position of the maximum depth, displays a thickness which is less than 15% of the distance between the rotational axis and the distal edge.