A wave energy converter includes a buoyant body and an acceleration tube with a working cylinder and working piston movable therein, a mooring system, and at least one energy collecting device including a hydraulic pump in the form of a hydraulic cylinder having a jacket and an internal pump piston connected to at least one piston rod, which forms a mechanical connection between the buoyant body and the working piston in the working cylinder, wherein at least one float body having a buoyancy in the body of water where the wave energy converter operates is connected to the working piston and wherein the buoyancy of the float body is adapted to maintain the working piston in a desired vertical operating range in the working cylinder when the wave energy converter.