Viability of Natural Gas in Fuel Cell Traction for Heavy Freight Locomotion: Economic, Efficiency, and Technology Factors

Abstract

Recent changes in the cost and the availability of natural gas (NG) have sparked interest in applying fuel cell (FC) technologies to commercial shipping to take advantage of beneficial market factors. Historically, FC technology has been primarily developed for private automobiles and faces considerable economic and logistical barriers, including cost, range, durability, and refueling infrastructure. Serendipitously, the rail industry has been investigating NG as a supplement to diesel fuel, which accounts for a large portion of its operating expenses. This study investigated the economic and technology factors that determined fuel efficiency and emissions advantages of FC technologies applied to NG locomotives. Results indicated that economic advantage would come either from the price of NG and diesel fuel diverging in the future or from the development of two key FC technologies, which would mitigate the disadvantages of FCs and make them economically superior to diesel fuel. These technologies are variable-output solid-oxide FCs and hot start-up optimization. Two configurations are suggested: high-temperature responsive multistack and dual-temperature responsive multistack. Both are discussed with proposed configurations and estimated benefits. These recommendations are the opposite of those required for private automobiles. Breakeven prices for liquefied NG are estimated for nine distinct drive train configurations.