Device for energy recovery for an electrically driven motor vehicle, preferably a commercial vehicle, the device comprising: an electric drive unit for driving the motor vehicle; a permanent brake device, which is designed as a hydrodynamic retarder and is drivingly connected or connectable to the electric drive unit; and a waste heat recovery device with an expansion machine, which is connected or connectable to the permanent brake device for energy recovery from a waste heat resulting from the braking of the permanent brake device wherein: the waste heat recovery device comprises a, preferably fan-cooled, cooler, preferably a condenser or a gas cooler, which is arranged downstream of the expansion machine, characterized in that the waste heat recovery device comprises an intermediate heat exchanger, which is arranged for thermal coupling of a fluid line upstream of the cooler to a fluid line downstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the intermediate heat exchanger; or that the waste heat recovery device comprises a cooler bypass, which bypasses the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the cooler bypass; or that the waste heat recovery device comprises a heat exchanger, preferably an evaporator or a preheater, a heat pump of the device, which is arranged for thermal coupling to a fluid line upstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the heat exchanger. an electric drive unit for driving the motor vehicle; a permanent brake device, which is designed as a hydrodynamic retarder and is drivingly connected or connectable to the electric drive unit; and a waste heat recovery device with an expansion machine, which is connected or connectable to the permanent brake device for energy recovery from a waste heat resulting from the braking of the permanent brake device wherein: the waste heat recovery device comprises a, preferably fan-cooled, cooler, preferably a condenser or a gas cooler, which is arranged downstream of the expansion machine, characterized in that the waste heat recovery device comprises an intermediate heat exchanger, which is arranged for thermal coupling of a fluid line upstream of the cooler to a fluid line downstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the intermediate heat exchanger; or that the waste heat recovery device comprises a cooler bypass, which bypasses the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the cooler bypass; or that the waste heat recovery device comprises a heat exchanger, preferably an evaporator or a preheater, a heat pump of the device, which is arranged for thermal coupling to a fluid line upstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the heat exchanger. the waste heat recovery device comprises a, preferably fan-cooled, cooler, preferably a condenser or a gas cooler, which is arranged downstream of the expansion machine, characterized in that the waste heat recovery device comprises an intermediate heat exchanger, which is arranged for thermal coupling of a fluid line upstream of the cooler to a fluid line downstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the intermediate heat exchanger; or that the waste heat recovery device comprises a cooler bypass, which bypasses the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the cooler bypass; or that the waste heat recovery device comprises a heat exchanger, preferably an evaporator or a preheater, a heat pump of the device, which is arranged for thermal coupling to a fluid line upstream of the cooler, and a valve device, which is arranged to adapt a fluid flow through the cooler and/or the heat exchanger.