A chronological history of power evolution, from steam railcars to hydrogen electric railcars
Early stage
Steam railcar
A type where a boiler was mounted on a part of the vehicle. Due to the nature of steam engines, miniaturization was difficult, so it did not spread widely.
Korean examples: Suryo Line and Suin Line Sig-type steam railcars
Early stage
Gasoline railcar
A method of mounting a gasoline engine under the vehicle. It was difficult to produce high output, so it was used limitedly on routes with low transport volume.
Non-electrified section
Diesel Multiple Unit (DMU)
Divided into hydraulic types using torque converters and diesel-electric types that drive generators to power electric motors. The mainstay of non-electrified sections.
Korean examples: NDC, DHC, CDC, RDC series
Urban rail
Electric Multiple Unit (EMU) · Commuter type
Receives electricity from overhead lines to drive traction motors in each car. The most common type of railcar encountered today.
Korean examples: Seoul Metropolitan Subway lines 1-9, etc.
High-speed rail
Distributed power high-speed train
Power is distributed across all cars without a locomotive, which is advantageous for both seating capacity and acceleration/deceleration performance. Evaluated as suitable for the domestic environment with many stops.
Korean examples: KTX-Eum (EMU-260), KTX-Cheongryong (EMU-320)
Transition period
Hybrid diesel railcar
A transitional model that improves fuel efficiency and emissions by using a battery in conjunction with a diesel engine. It is in the trend of replacing hydraulic diesel railcars.
Next generation
Hydrogen electric railcar · Battery railcar
Runs on catenary-free sections using fuel cells or large-capacity batteries. The biggest strength is the ability to operate without overhead lines.
Hyundai Rotem, aiming to commercialize hydrogen railways for all vehicle types by 2030