Based on a multidisciplinary and configurable modeling approach, this work deals with the optimal choice and the design of a hybrid propulsion with the associated power management strategy to replace a conventional propulsion in a low tonnage river ferry operating on short cycles, with the aim of reducing its environmental impact and the costs over its entire lifetime. The considered ferry is used for the transport of people and vehicles crossing the Seine river, with an installed propulsive power of 330 KW. The operating cycle of the ferry and the energy consumption of its classical propulsion have been determined experimentally and then used as references in simulations for validation and comparison purposes. Two hybrid structures involving the use of batteries and supercapacitors were proposed and compared. It is shown that the hybridization leads to a substantial reduction in CO₂ emissions. The supercapacitor- and battery-based hybrid structures lead respectively to 18% and 29.7% CO₂ reduction compared to classical propulsion, representing, respectively, about 382 and 626 tons of CO₂ reduction over 20 years of operation. Despite the fact that the use of batteries leads to a more significant reduction in CO₂ emissions, the solution using supercapacitors is chosen following a technical-economic study over 20 years of operation.