Dual Fuels for Trains and Ships

Posted: October 13, 2013

A look at the use of natural gas in transportation for rail and marine transportation
photo from

photo from

Natural gas powered vehicles and trucks are common news, but companies are looking at  powerful engines for trains and ships that can run on both natural gas and diesel.  GE Global Research is working on a train engine that will run on both diesel and up to 80% of natural gas.  There are many benefits of this research.  With natural gas prices lower than diesel, the cost of diesel is many times more expensive than natural gas per unit of energy.  Having the capability of running on more than one source is beneficial if the price of natural gas goes up or in obtaining the resources.   Natural gas emits less carbon dioxide than diesel, thus greenhouse gas emissions can be reduced.  This will be important in meeting the stricter EPA  air pollution regulations required by 2015 for locomotives.   Modifications to a diesel engine to run on both diesel and natural gas are relatively easy. 

Although dual fuel engine technology was discovered in the 1960’s, it is the lower natural gas prices that are promoting the study of this technology in depth.  One of the largest train companies, BNSF, is testing dual fuel engines for their trains.  Although the conversion to dual fuel engines has a higher price tag and lacks infrastructure of stations, trains running on fixed routes or tracks will have an advantage in setting up natural gas fueling infrastructure.  Fuel tank safety would have to be approved by federal regulators, and special tankers to carry the compressed natural gas, and worker training are other considerations in making the transition.   Canadian National Railway converted two trains to a diesel-natural gas mix in September, 2012.  The company stated there were "mechanical and fuel logistics challenges" with widespread conversion and that it was too early to determine if the pilot program was successful.

Wärtsilä, a Finnish company, was selected to provide China with the world’s first diesel-LNG engines used in tugboats.  The company was also selected to produce the same type of engine for a ferry operating in the Saint Lawrence River in Quebec.  The American Clean Skies Foundation (ACSF) released a report last year looking at natural gas for marine vessels.  The report stated that economics of any specific project would hinge on vessel fuel use, LNG prices, and vessel conversion costs.   Stricter EPA emissions regulations  requiring more expensive low sulfur fuels for marine vessels could also be a an important factor

With the increase in natural gas production and advances in technology, it is important to start looking at alternative fueling options for rail and marine transportation, especially with the changing economic and regulatory environment.