A turbine arrangement for controlling a gas flow, in particular for a fuel cell (2) or for an internal combustion engine (3), and a charging device having such a turbine arrangement, is described, in which the gas flow supplied by an inlet (10) can be controlled by an adjustable slide bushing (48) covering an entry opening (43) to form a turbine wheel (38) arranged in a turbine housing (30) between a closed position and an open position, such that, in the closed position, the gas flow is throttled and, in the at least partially open position, a controllable proportion of the gas flow drives the turbine wheel (38) arranged on a shaft (22) of an electric engine (18) functioning as a generator for recuperating energy, wherein the slide bushing (48) releases a wall opening (64) in the turbine housing (30) above a predetermined value of the gas flow, such that a bypass channel emerges in order to guide gas flow past the turbine wheel (38) directly to an outlet opening (24).