CANADA: Canadian National is testing two Electro-Motive Diesel locomotives which have been converted to use natural gas for 90% of their fuel needs, with diesel used for ignition. CN is also working on a long-term project to develop a natural gas locomotive and a standardised gas tender.

The two 3000 hp SD40-2 locomotives are operating in revenue service on the 450 km Edmonton - Fort McMurray route. They have been retrofitted with natural gas conversion kits supplied by Energy Conversions Inc, which expects that gas/diesel hybrid fuelling will reduce CO2 emissions by 30% and NOx emissions by 70% over a locomotive duty cycle.

Chart Industries upgraded a tank wagon as a tender to carry the gas, which is provided by Encana Corp. Fuelling and maintenance takes place in Edmonton.

'CN launched this locomotive test to explore the use of natural gas as a potential alternative to conventional diesel fuel', said Chief Operating Officer Keith Creel. 'Natural gas has a lower carbon content compared with diesel fuel, so that locomotives using natural gas - if the railway technology employing this form of energy ultimately proves viable - would produce significantly fewer carbon dioxide emissions.'

CN is also developing a 'state-of-the-art' natural gas engine and standardised tender in partnership with EMD, Westport Innovations and Gaz Métro Transport Solutions. CN is to provide two 4 300 hp SD70M-2 locomotives, and EMD will integrate the natural gas engine and controls, including Westport high-pressure direct injection and gas technologies. GMTS will develop gas liquefaction and distribution systems, with a gas tender to be jointly developed by the project partners.

Laboratory tests are planned for 2013, before trials with prototype locomotives in 2014.