After a successful experimental run with compressed natural gas (CNG), Indian Railways has set its eyes on liquefied natural gas (LNG) as an alternative fuel option. The transporter is awaiting regulatory approvals for conducting trials.

LNG requires less storage space than CNG which makes it a more efficient and convenient option. By storing LNG in the same space as CNG, trains can run for three times the distance, according to experts. The CNG experiment was conducted on 21 trains.

Of the trains running on CNG, 20 are in the Northern Railways and one in Vijayawada region (South Central Railway). A decision on scaling up CNG train-run experiment depends on whether more refueling stations can be set up.

Theoretically, use of CNG resulted in 8-11 per cent savings against a similar train running on diesel. However, in CNG-based trains, the Railways has fitted cascades, a group of cylinders, with storage space for CNG that takes away the space equivalent to a third of a full coach. Replacing the energy storages with seats, would have resulted in extra revenue for the Railways. Now, it wants to try out LNG as alternative fuel and estimate the savings it can make.

“In the space allocated for CNG storage in trains, Railways can store LNG, which will generate three times the energy. In simple terms, same amount of LNG stored in the space meant for CNG can haul a train for a much longer distance without requiring refueling, and thus without having to stop,” Subodh Kumar Sagar, Chief Mechanical Engineer, Indian Railways Organization for Alternate Fuels (IROAF), said in a conference recently.

Railways needs a regulatory mechanism to install the storage in trains, and in terminals, from Lucknow-based Research Designs and Standards Organization (RDSO) and Nagpur-based Petroleum Explosive Safety Organization.