The present invention relates to a propulsion arrangement for a marine vessel, which propulsion arrangement comprises an internal combustion engine, a shaft arrangement and a steerable thruster unit. The marine vessel further comprises an electric generator or a combined electric generator and motor in connection with the propulsion arrangement. In order to reduce space requirements and required equipment as well as to raise efficiency, the shaft arrangement comprises a main shaft extending from the internal combustion engine to a first angle gear and a drive shaft extending from the first angle gear to a second angle gear in the steerable thruster unit. The electric generator or the combined electric generator and motor is connected to the drive shaft of the shaft arrangement after the main shaft and the first angle gear are connected thereto.