Two posts from Green Car Congress on cleaner locomotives:
The train was developed by Svensk Biogas, which converted an old Fiat locomotive by replacing the diesel engines with two Volvo gas engines. The train is equipped with eleven canisters containing enough gas to run for 600 kilometers (375 miles) before needing a refill, and can reach a maximum speed of 130 kilometers (80 miles) per hour.
Biogas refers to methane produced by the anaerobic digestion of biomass waste. (Aerobic decomposition, or composting, requires large amounts of oxygen and produces heat.)
Biogas produced in anaerobic digesters consists of methane (50%-80%), carbon dioxide (20%-50%), and trace levels of other gases such as hydrogen, carbon monoxide, nitrogen, oxygen, and hydrogen sulfide.
The cargo and passenger train, which runs along the world’s highest railway at 16,076 feet (4,900 meters) above sea level in Peru’s central Andes, will switch from diesel to run on two CNG engines designed by General Electric.
Ferrocarril Central Andino, 82% owned by Peruvian capital and 18% owned by US-based Railroad Development Corp. (RDC), has operated the line between Lima and the central Huancayo region since 1999. The company says it plans to convert all eight engines in its fleet to CNG from diesel in the next seven months.
The engines, which had been under test for some time and as described in Latin Tracks in 2004 are dual-fuel capable, with diesel as a backup for certain sections when the trains are working upgrade. A slug unit will carry the CNG tanks.