LNG power: A history lesson

Written by William C. Vantuono, Editor-in-Chief
Steve Ditmeyer

Is LNG the locomotive fuel of the future? Will it, over time, replace diesel, much like diesel supplanted steam during the 1940s and 1950s? Or will it be used in combination with diesel, deployed on specific runs where it makes the best logistical and economic sense? What about the safety concerns? The fueling infrastructure required?

These and other questions are under consideration as the industry—most notably BNSF Railway, Union Pacific, and CN—move ahead with evaluating LNG technology.

My “From the Editor” column in the May 2013 issue of Railway Age, in which I quoted Contributing Editor Bruce Kelly on crew-safety concerns, raised quite a few eyebrows in the industry and sparked some internal debate. That’s a good thing—one of the purposes of a trade magazine. And of course, for me as the magazine’s chief editor, it’s gratifying to know that readers are paying attention!

Steve DitmeyerOne of the raised eyebrows is that of Steve Ditmeyer (pictured, top), who in a long and distinguished rail industry career was Director of R&D at the Burlington Northern Railroad at the time BN experimented with LNG. He also has served, at one time or another, at the Federal Railroad Administration, Morrison Knudsen Corp.’s Locomotive Division, and the Industrial College of the Armed Forces. He is currently Principal of his own consulting firm, Transportation Technology and Economics, and an instructor in Michigan State University’s Certificate Course in Railway Management. Steve is by nature a modest gentleman, so I hope he isn’t too uncomfortable with me saying he is one of the rail industry’s most brilliant people.

First, I’d like to preface Steve Ditmeyer’s comments with a few from Bruce Kelly:

“My comments about BN’s prior use of [diesel] fuel tenders were meant as a heads-up to the Railway Age staff and to the industry that any future in-depth discussion about LNG must extend beyond the subject of cost and emission advantages alone. The mechanical and operational aspects of running a railroad with LNG deserve coverage as well, but so far there’s been very little of it. Much has been learned and developed since the use of diesel and LNG fuel tenders in the 1980s and 1990s, and that’s where I was intending to steer the discussion.

“As for what some have described as ‘concern’ about safety training for servicing and train crews around LNG, those were among the issues raised early on in the Wall Street Journal and other news outlets in the days and weeks following BNSF’s announcement that it was moving ahead with testing of LNG locomotives. Again, my mention of those issues was not meant to alarm (although storage, handling, and operation around LNG will be a significant change from current diesel practices). I was simply pointing out matters that the mainstream media had raised, and which Railway Age and the industry should eventually respond to.”

That is exactly what’s happening.

And now for a history lesson in LNG locomotives from Steve Ditmeyer. Pay close attention!

“I too am concerned about the wild exuberance of some analysts regarding the likelihood of a widespread and rapid transition to LNG as a locomotive fuel (your “From the Editor” column, May 2013). However, I am even more concerned about the negativity regarding the feasibility and economics of the use of LNG on railroads.

“Published papers about the BN’s LNG locomotive program addressed these issues. The program won the Association of American Railroads’ ‘Outstanding Technological Achievement Award’ for 1992, and BN’s two LNG locomotives ran in revenue service between coal mines in Montana and power plants in northern Minnesota as well as to BN’s coal piers at Superior, Wisc., from 1991 to 1995.

Natural bn7214ac fuel tender“Kelly mentioned that BN’s diesel tender cars (three photos following Ditmeyer’s) in the 1980s ‘developed frame and/or drawbar fatigue,’ but they were existing tank cars that were modified for tender car service. BN’s two LNG tender cars (three lower photos) that were specially designed and built in 1990 were constructed to withstand the buff and draft forces within the locomotive consist. They were analyzed with the AAR’s Train Operations and Energy Simulator (TOES) at TTC and approved by the AAR’s Tank Car Committee and by the FRA’s Office of Safety before being put into service. These LNG tender cars were built with strengthened center sills and had frame-braced trucks to reduce the likelihood of truck hunting.

bnft28 47b2“The cost of diesel fuel today is approximately five times the cost of natural gas per unit of energy (LNG measured in BTUs). Diesel fuel cost only twice as much natural gas per unit of energy back in the mid-1990s, which is why BN did not implement LNG locomotives after the demonstration ended in 1995. I believe that the technology for LNG locomotives has been proven, and that the logistics and infrastructure for them, while different from those for diesel fuel, are well within the capabilities of today’s railroads. LNG locomotives today make economic sense on certain routes on certain railroads, but definitely not on all routes on all railroads. The economic rate of return on an investment in LNG locomotives is highest on routes where locomotive utilization rates are highest and where they burn the most fuel.

“As to the matter of ‘special safety concern for refueling crews and train crews,’ I wrote in my ASME (American Society of Mechanical Engineers) paper, which is in the public domain on the web: ‘BN has undertaken extensive training of train crew members and maintenance shop personnel along the Northern coal corridor to make them aware of procedures for handling methane fuel. Briefings were also given to fire departments and emergency response teams in communities through which the gas-fueled locomotives and tender cars are operating.’

02-0530-w leiter2“BN’s project partner, Air Products and Chemicals, Inc., which was (and still is) in the business of safely handling gasses and cryogenic liquids, operated the fueling station at Staples, Minn., because railroad employees did not have those specialized skills. All the railroads now working on LNG locomotives have copies of this paper and presumably are learning from the steps that BN took 20 years ago.

“To understand safety issues regarding LNG, BN contracted in 1990 with the Los Alamos National Laboratory for a Safety Analysis of Alternative Locomotive Fuels. As expected, the analysis showed that diesel fuel was the safest locomotive fuel, LPG (propane) the most hazardous, and LNG, CNG, and methanol fell between them. This report was given to FRA and the NTSB and was placed in the public domain in the National Technical Information Service. It has been distributed to all the railroads currently working on LNG locomotive projects.

fanpix8“Being aware of the issues the diesel fuel fuel tender cars were having, we in BN R&D had our supplier design and construct two cryogenic LNG tender cars explicitly for running in the locomotive consists so that the problems that the diesel fuel tender cars experienced could be avoided. As I mentioned, AAR staff analyzed the BN LNG tender cars with their TOES simulator, and the AAR Tank Car Committee and the FRA Office of Safety approved the designs for them. Other LNG tender cars built since then have been built using the same criteria.

4532.LNG-locomotivesBN7149r800“In the years that BN operated LNG-fueled locomotives, I never once heard a crew complain that an LNG tender car blocked their way back to another locomotive in the consist. The only thing I had crews complain about to me was that the LNG-fueled locomotives were not being assigned to their runs often enough. We had a local chairman of the Brotherhood of Locomotive Engineers who went to local meetings to advocate for the LNG project.

“The Russian Railways designed an LNG tender car 20-plus years ago that had four smaller, narrow LNG tanks mounted within a carbody that had an internal walkway. The problem with this arrangement is that the Russian LNG tender car contained much less LNG than BN’s LNG tender car, thus reducing the range of the Russian LNG locomotive and requiring more frequent stops for refueling. We on BN recognized that these were trade-offs, and we made a conscious decision to have higher-capacity LNG tender cars without walkways.”

Steve adds that he doubts that he will be able to provide any insight or information about any of the LNG locomotive testing and demonstration programs now under way on any of the major railroads, because, he says, “as I am sure you are aware, the railroads today are much more tight-lipped about any of their technology programs than we were 20 years ago.”

CN-LNG-locomotiveFrom my perspective as a journalist for a publication whose mission is to facilitate communication and share knowledge, that’s not a good thing! As one of my earliest predecessors said some time back in the 19th century, “A man is a damned fool who cannot learn from anybody’s experience but his own.”

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