Abstract: A rotating wave energy machine includes at least one rotor that revolves in a synchronous manner for utilizing an orbital flow of an undulating body of water that circulates over the rotor. An output power is tapped at a rotor shaft and the power (in the power flow) is converted by at least one lift device of the rotor. A cross-section of the lift device includes at least one curve or angle that is shaped depending on a curve of a total flow. The at least one angle or curve is configured such that the influence of the relative flow on the total flow is taken into account. When the rotating wave energy machine is operational, the relative flow is superposed on the circulating orbital flow that acts on the lift device from outside, and a total flow is produced which is curved about the rotor shaft.