Japan: Kinki Sharyo has built the DEC743-series diesel-battery machines. JR West has ordered nine of them, along with 12 hopper-dosing wagons to run with them.
JR West has not disclosed full specifications. Each locomotive reportedly weighs 55 t, reaches up to 75 km/h and runs on lines with a track gauge of 1,067 mm. An electric transmission drives the machine, and the batteries store energy recovered under regenerative braking, which trims both fuel use and emissions.
To keep maintenance costs down, JR West has built the DEC743 largely around the same design and equipment as the diesel and electric multiple units it already runs. The twin-cab railcar-type carbody sits on two powered two-axle bogies. The diesel-generator set goes beneath the floor and the traction batteries on the roof, with the converters, braking systems and other auxiliary equipment inside. Power comes from a 331 kW Komatsu SA6D140HE-3 diesel engine and a Toshiba traction system, both common on Japanese passenger stock.
The locomotives should enter service in 2027, replacing the DE10 and DD51-series diesels that local manufacturers turned out in the 1960s and 1970s. Three of them — one principal unit and two spares — will also work the tourist push-pull train on the Sagano Railway, wearing a special livery and carrying extra safety systems. New coaches for that train are likewise due in 2027.
JR West already operates two machines of similar design and equipment: the single-car DEC700 railcar, used for service runs, and the two-car DEC741, which inspects track and overhead line equipment.
