The Biber was powered on the surface by a 32 hp (24 kW) Otto Blitz petrol engine, which was used despite concerns about the risks posed by the carbon monoxide the engine gave off.[1] The engine had the advantage of being cheap and available in large numbers.[1] Propulsion while submerged was provided by a 13 horsepower (9.7 kW) electric motor, supplied by three Type T13 T210 battery troughs.[1]