Diesel–electric transmission

A Diesel–electric transmission, or diesel–electric powertrain, is used by a number of vehicle and ship types for providing locomotion.

A diesel–electric transmission system includes a diesel engine connected to an electrical generator, creating electricity that powers electric traction motors. No clutch is required. Before diesel engines came into widespread use, a similar system, using a petrol (gasoline) engine and called petrol–electric or gas–electric, was sometimes used.

Diesel–electric transmission is used on railways by diesel electric locomotives and diesel electric multiple units, as electric motors are able to supply full torque at 0 RPM. Diesel–electric systems are also used in submarines and surface ships and some land vehicles.

In some high-efficiency applications, electrical energy may be stored in rechargeable batteries, in which case these vehicles can be considered as a class of hybrid electric vehicle.

The first diesel motorship was also the first diesel–electric ship, the Russian tanker Vandal from Branobel, which was launched in 1903. Steam turbine–electric propulsion has been in use since the 1920s (Tennessee-class battleships), using diesel–electric powerplants in surface ships has increased lately. The Finnish coastal defence ships Ilmarinen and Väinämöinen laid down in 1928–1929, were among the first surface ships to use diesel–electric transmission. Later, the technology was used in diesel powered icebreakers.

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