The feasibility and potential benefits of converting 10 remaining U.S. flag Great Lakes steamship bulk carriers to liquefied natural gas (LNG) propulsion using gas engines is investigated. This is the final report of a study that was initially reported at the February 24, 2012, SNAME Section Meeting in Cleveland, OH. The evolving marine air emissions standards and the movement to LNG fuel in U.S. and international non-LNG carriers and the general case for the possible conversion of the remaining U.S. flag Great Lakes steamship bulk carriers to LNG fuel were outlined in the initial report. In this sequel, the final results of a conceptual design study on the conversion of the three AAA class vessels (SS Arthur M. Anderson, SS Cason J. Callaway, SS Philip R. Clarke), focusing primarily on operational and arrangement feasibility and remaining life-cycle economics, are presented. Three cases, a pure diesel conversion, a single-fuel LNG conversion, and a dual-fuel LNG/diesel conversion, are compared.
