Diesel locomotive Calabro Lucane in southern Italy in 1926, following trials in 1924-5. In 1924, two diesel–electric locomotives were taken in service by the Soviet railways, almost at one time: In 1935, Krauss-Maffei, MAN and Voith built the first diesel–hydraulic locomotive, called V 140, in Germany. The German railways (DRG) being very pleased with the performance of that engine, diesel–hydraulics became the mainstream in diesel locomotives in Germany. Serial production of diesel locomotives in Germany began after World War II. In many railway stations and industrial compounds, steam shunters had to be kept hot during lots of breaks between scattered short tasks.
Electro-diesel locomotive whose electricity source is overhead line include: In 2010, Bombardier had plans, apparently known as "Operation Thor" or "Project Thor", to convert 500 existing diesel multiple units (DMUs) into electro-diesel multiple units (EDMUs). Whilst exact details are unclear, one source specified that these would involve their Voyager family DEMUs, and entail the construction of additional intermediate cars with a pantograph and a transformer which would feed power into the traction motors of the existing diesel-electric cars when running off overhead lines. Several, primarily diesel locomotive types and a multiple-unit have been built to operate off a third rail into the