An underwater power generation system (10) comprising at least one continuous track (30); a plurality of carriages (60) that are movable around said track, at least one foil (40) attached to each of the carriages, said foils ale to be driven by a-water current; at least one line member connected to the carriages; at least one power take-off (50) operatively connected to said line member; wherein the driven foils cause the carriages to move around said track and hence cause movement of said line member to power said power take-off.
