Michael E. Iden

Battery Storage of Propulsion-Energy for Locomotives

Significant technical, regulatory and media attention has recently been given to the use of electrical storage batteries onboard a line-haul (long-distance) locomotive or “energy storage tender” (coupled adjacent to a locomotive) as a means of improving railroad fuel efficiency and reducing freight locomotive exhaust emissions. The extent to which electrical energy stored onboard could supplement or replace diesel generated power has yet to be quantified or proven. There are significant technical design, maintainability, logistical and safety challenges to making this technology commonplace, especially for over-the-road (line-haul) freight trains.The use of electrical batteries to provide some amount of point-source fuel- and/or emissions-free locomotive power is not a new concept. Recent claims that onboard storage of locomotive propulsion energy is “new locomotive technology” are unfounded. The world’s first all-battery-powered locomotive was built in 1838 only 34 years after the world’s first steam locomotive operated. A total of 126 identifiable locomotives using onboard batteries to store propulsion energy have been built and operated to some extent in the United States (US) since 1920. Almost all were low-power switching locomotives and none are currently in revenue freight service. Two high-horsepower line-haul experimental engineering test locomotives with an experimental battery design and regenerative dynamic braking have been built (in 2004 and 2007) but very little revenue service testing has occurred.This paper reviews propulsion battery-equipped locomotives over the past 95 years in the US, and discusses future options and possibilities including the technical and logistical challenges to such propulsion.Capturing dynamic braking energy (developed by locomotive traction motors during deceleration or downhill operation) could be a source of onboard battery recharging, but will require significant additional locomotive control system development work to achieve practicality. New battery technologies are being developed but none are yet practical for large-scale locomotive applications. Retrofitting of large amounts of onboard battery storage on existing (or even future) diesel-electric locomotives will be limited by onboard space constraints. The development and use of energy storage “tenders” will bring complications to locomotive and train operations to make effective use (if commercialized) practical and safe.This paper is also intended to provide technical background and clarity for various regulatory agencies regarding battery energy storage technologies for future locomotive propulsion.Copyright

PR30C-LE Locomotive With DOC and Urea Based SCR: Field Trial and Emissions Testing After 1,500 and 3,000 Hours of Operation

This paper details part two of the demonstration of a 2,240 kW (3,005 HP) PR30C-LE locomotive with exhaust aftertreatment containing diesel oxidation catalysts (DOC) and urea-based selective catalytic reduction (SCR). The PR30C-LE is a remanufactured and repowered, six-axle, diesel-electric, line-haul locomotive. Program objectives were to measure emission levels of the locomotive and record locomotive and aftertreatment operations during a 12 month revenue service field trial. Phase 1 of the program involved engine baseline emissions testing as well as emissions testing with the aftertreatment at the beginning of its useful life, or the 0-hour condition. Results from Phase 1 showed engine-out emission levels were within U.S. EPA Locomotive Tier 2 limits. With aftertreatment at beginning of useful life, hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) were below Tier 4 limits, and particulate matter (PM) was below Tier 3 limits.Phase 2 consisted of a 12 month revenue service field trial and additional emissions testing completed at the midpoint and end of the field trial. On-board GPS data, aftertreatment NOx sensor data, and various locomotive operating parameters were logged continuously during the field trial. The field trial data suggests the impact SCR technology has on locomotive NOx emissions is driven primarily by locomotive utilization and loading factor. Overall the field trial included 3,082 hours of operation and PRLX3004 generated approximately 572 MW-hours of work over the 12 month period. Emission test results at the 1,500-hour and 3,000-hour conditions showed very little change from 0-hour test results. Emission levels remained below Tier 4 limits for HC, CO, and NOx, and below the Tier 3 limit for PM. Phase 2 test results suggest there was no significant degradation in emissions performance during the field trial, and no major issues with the locomotive and aftertreatment were detected. In total there are currently five PR30C-LE locomotives in operation within California and Arizona. Together they have completed a cumulative 30,800 hours of revenue service through June 2012 without report of a major issue.Copyright

Locomotive Exhaust Temperatures During High Altitude Tunnel Operation in Donner Pass

Locomotives in heavy-haul service at high altitude and within unventilated tunnels operate under some of the most extreme conditions encountered in the U.S. with regard to high ambient temperatures and high locomotive exhaust temperatures. Consideration of such conditions is crucial to the design of future catalytic emission control systems for locomotives. Field testing was conducted on two locomotives certified to U.S. Federal Tier 2 locomotive emissions standards operating as part of a four-locomotive consist pulling a heavy-freight train west-bound through the Donner Pass Region in late August 2007. The highest post-turbine exhaust temperatures observed over the entire test route occurred within Union Pacific Tunnel 41 — an approximately two-mile-long, unventilated tunnel located near Norden, California. Engine protection measures within the electronic locomotive and engine management systems of both locomotives limited the peak exhaust temperatures encountered during the tests to less than 560°C.Copyright

Crashworthiness Progress: U.S. Freight Locomotives, 1990-2014

The design of freight locomotives for U.S. railroads began changing in late-1990 with the introduction of the first industry crashworthiness standard for the front nose of newly-manufactured freight. Between 1990 and 2008, that industry standard was revised and upgraded four times. In 1995 an industry standard for the crashworthiness of fuel tanks mounted underneath newly-manufactured freight locomotives was also introduced. Effective at the end of 2008, both of the industry standards were incorporated by reference into a new U.S. federal regulation mandating crashworthiness features on newly-manufactured locomotives effective with deliveries to railroads in 2009.In addition to the crashworthiness-specific design changes, in 1992 and 1993 both of the major U.S. locomotive manufacturers introduced new designs for the attachment of the truck (bogie) assemblies to locomotive underframes; these changes were to facilitate the use of new trucks (bogies) producing higher adhesion for greater tractive effort. The “deep traction pin” designs also had a positive effect on the crashworthiness of new fuel tanks by reducing the chance of truck separation from the underframe (and impacting the fuel tank) during accidents. The changes cited here were for newly-manufactured freight locomotives, with retrofit to older locomotives impossible or extremely difficult to accomplish with similar results.This paper briefly reviews the introduction of the crashworthiness features described, and also offers the first retrospective look at (a) how extensively the evolving crashworthiness features have reached across the U.S. freight locomotive fleet (through acquisition of newly-manufactured freight locomotives) and (b) attempts to measure the effectiveness of the various crashworthiness design changes in saving lives and reducing injuries of in-cab railroad employees.It is believed that this paper is the first and only assessment to date of cumulative U.S. freight locomotive crashworthiness progress and its statistical impact on locomotive crew safety since the early 2000’s.Copyright

PR30C-LE Locomotive With DOC and Urea Based SCR: Baseline and Initial Aftertreatment Emissions Testing

The PR30C-LE is a repowered six-axle, 2,240 kW (3,005 hp), line-haul locomotive that was introduced to the rail industry in 2009. The Caterpillar 3516C-HD Tier 2 engine is equipped with an exhaust aftertreatment module containing selective catalyst reduction (SCR) and diesel oxidation catalyst (DOC) technology. PR30C-LE exhaust emission testing was performed on test locomotive PRLX3004. Phase-1 of the test program included the following tasks: engine-out baseline emissions testing without the aftertreatment module installed, aftertreatment module installation, commissioning and degreening, and emissions testing with the aftertreatment. Emission results from testing without the aftertreatment module, referred to as the baseline configuration, indicated that PRLX3004 emissions were below Tier 2 EPA locomotive limits without aftertreatment. Emission test results with the DOC and SCR aftertreatment module showed a reduction in nitrogen oxides (NOx) of 80 percent over the line-haul cycle, and 59 percent over the switcher cycle. Particulate matter (PM) was reduced by 43 percent over the line-haul cycle and 64 percent over the switcher cycle. Line-haul cycle composite emissions of Hydrocarbon (HC) and carbon monoxide (CO) were reduced by 93 and 72 percent, respectively. The PR30C-LE locomotive achieved Tier 4 line-haul NOx, CO, HC, as well as Tier 3 PM levels. There are currently five PR30C-LE locomotives in operation in California and Arizona, and the total hour accumulation of the five PR30C-LE locomotives as of October 2011 was 20,000 hours.Copyright

Experimental Exhaust Gas Recirculation (EGR) on EMD SD59MX 2.238 Megawatt Diesel-Electric Freight Locomotives

In July 2008, Union Pacific Railroad (UP) and Electro-Motive Diesel, Inc. (EMD) began discussions to jointly investigate the potential for exhaust gas recirculation (EGR) on a small group of re-powered UP locomotives, to assess the potential for EGR as a technology to meet the oxides of nitrogen (NOx) requirement in US Environmental Protection Agency (EPA) Tier 4 locomotive emissions regulations on newly-manufactured future diesel locomotives effective January 1, 2015 [1].After several years of research, engineering and experimental testing, EMD began delivering to UP in late-2011 nine SD59MX experimental locomotives equipped with prototype EGR technology as a first step to achieving Tier 4 NOx reductions, plus a tenth SD59MX unit equipped with both the EGR technology and an experimental whole-engine aftertreatment package to migrate toward Tier 4 particulate matter (PM) levels on future new Tier 4 locomotives. Compared to today’s Tier 2 emission limits, the EGR equipped SD59MX produces 42 percent less NOx, a significant step toward the development of new Tier 4 locomotives.Copyright

NOx Reducing and Aftertreatment Technologies for EPA Tier 4 Locomotives: Railroad Perspective and Expectations

The year 2015 will be a landmark year in locomotive technology in the United States. Effective January 1st of that year, newly-manufactured U.S. line-haul and switch service (freight-and-passenger) locomotives must be manufactured to meet the fifth level of U.S. Environmental Protection Agency (EPA) emissions regulations since 2000. Achieving those emission levels will require aftertreatment technology in some form. Also effective December 31st of that year, U.S. railroads will be required to have in operation (on much of the rail network)1 a federally-mandated Positive Train Control (PTC) technology for collision avoidance. Class I U.S. freight railroads2 by the end of 2015 will have invested an estimated

DRAG REDUCING DEVICES FOR STACKED INTERMODAL RAIL CARS

5.8 billion in PTC technology, with a major emphasis on interoperability of PTC-equipped locomotives between different railroads. An estimated 17,000 locomotives will be retrofitted or equipped with PTC by the end of 2015 and most if not all newly-manufactured locomotives will be PTC equipped after 2015. For perspective, the U.S. freight railroad investment in PTC is roughly what the Class I railroads have spent the past 4–5 years combined on capital expenditures related to infrastructure expansion. This convergence of two new complex locomotive technologies in 2015 will create a large challenge, especially in locomotive maintainability, for freight railroads. Locomotive builders and aftertreatment suppliers must work together to provide Tier 4 locomotives with minimal impact on railroad operations. U.S. diesel locomotives share a common internal combustion engine technology with most Class 8 over-the-road diesel trucks, but the railroad and locomotive environment is very different from the highway truck environment, and a “cookie cutter” approach to replicating diesel truck aftertreatment on locomotives should be avoided. New EPA Tier 4 diesel locomotives should not be viewed as “Tier 2 or Tier 3 locomotives with truck-type exhaust aftertreatment added”. Baseline reliability of current locomotive designs must also be improved to compensate for the added complexities of both exhaust aftertreatment and PTC. This paper is focused toward educating (1) aftertreatment technology manufacturers and system integrators and (2) locomotive design engineers. The emphasis is on assisting them in understanding the operating and maintenance expectations for Tier 4 aftertreatment-equipped line-haul locomotives, from the perspective of a major freight railroad.Copyright