Diesel locomotive Dv12s. In the 21st century series production standard gauge diesel–hydraulic designs include the Voith Gravita, ordered by Deutsche Bahn, and the Vossloh G2000, G1206 and G1700 designs, all manufactured in Germany for freight use. Steam-diesel hybrid locomotives can use steam generated from a boiler or diesel to power a piston engine. The "Cristiani Compressed Steam System" used a diesel engine to power a compressor to drive and recirculate steam produced by a boiler; effectively using steam as the power transmission medium, with the diesel engine being the prime mover The diesel-pneumatic locomotive was of interest in the 1930s because it
Diesel-Zarlatti locomotive Diesel-Zarlatti locomotive The Diesel-Zarlatti locomotive was a prototype railway locomotive, built in Italy in 1929, which adopted a hybrid diesel-steam transmission system. In the 1920s, there was a search for alternatives to the steam locomotive for railway traction, to reduce cost and improve efficiency. The main alternatives were railway electrification or the use of an internal combustion engine, such as the diesel engine. A disadvantage of the internal combustion engine was the need for a transmission system. One option to be explored was the conversion of an existing steam locomotive by fitting a diesel engine and an air compressor to