An electrical machine, e.g. water turbine or bow propeller includes a ring shaped stator ring and inside it a rotatable rotor ring with to it mounted blades flown around by the fluid. Magnetic elements generate axial directed magnetic forces between rotor and stator. Stabilizing elements keep the rotor during operation in an axial stable position. The magnetic elements include permanent magnets to generate an axial directed magnetic preload which is oppositely directed to the force exerted by the water to the rotor ring such that the axial force to be exerted by the stabilization means is smaller. The magnetic elements include the stator and rotor of the generator/motor, wherein the stator and rotor are behind each other, relative to the axial direction.