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
Electro-Motive Diesel 567 engine, introduced by their renamed Cleveland Diesel Engine Division in 1938. The new engine upgraded the horsepower of EMC's E series locomotives to 2000 per locomotive unit and increased reliability substantially. Also in 1938, EMC started to increase its reach up the chain of locomotive production by transitioning from General Electric equipment to in-house produced generators and traction motors. With Eugene Kettering moving to EMC that year, EMC moved into a leading role in further development of GM's locomotive engines. GM-Winton-EMC's long development efforts put the company in an advantageous position relative to other developers of Diesel-electric locomotion. Their