Utilizing LNG as a Fuel in Heavy-Duty Tractors

Recognizing the lack of operational data on alternative fuel heavy-duty trucks, NREL contracted with the Trucking Research Institute (TRI) in 1994 to obtain a cooperative agreement with Liquid Carbonic. The purpose of this agreement was to (1) purchase and operate liquid natural gas- (LNG-) powered heavy-duty tractor-trailers with prototype Detroit Diesel Corporation (DDC) Series 60 natural gas(S60G) engines in over-the-road commercial service applications; and (2) collect and provide operational data to DDC to facilitate the onroad prototype development of the engine and to NREL for the Alternative Fuels Data Center. The vehicles operated from August 1994 through April of 1997 and led to a commercially available, emissions-certified S60G in 1998. This report briefly documents theengine development, the operational characteristics of LNG, and the lessons learned during the project.