While working to reduce the environmental impact of diesel-burning locomotives, Norfolk Southern is exploring greener alternative fuel sources. The company has developed a prototype battery-powered switcher locomotive and in 2015 hopes to begin testing a prototype locomotive that runs on compressed natural gas.
Norfolk Southern is making headway on testing the feasibility of using compressed natural gas to power locomotives. During 2015, the company expects to begin testing a prototype GP38-2 switcher locomotive engine modified to run entirely on CNG.
The four-axle EMD yard switcher locomotive will be paired with a locomotive slug housing eight CNG cylinders supplying the equivalent of 1,000 gallons of diesel. Employees at Juniata Locomotive Shop are handling the conversion. Expectations are that a CNG-powered locomotive will generate significantly lower levels of nitrogen oxides, particulate matter, and hydrocarbons than a locomotive running on diesel.
“The potential to reduce emissions in rail yards located in urban areas is of interest to municipalities trying to reduce air pollutants to remain in compliance with federal clean air standards,” said Allen Rider, manager locomotive engineering and project leader.
“When we started this project about five years ago it was mostly about the possibility of a reduced-emissions locomotive, and we want to make absolutely sure that is the case before we go any further with this.”
Longer-term, Norfolk Southern is looking into converting EMD SD70ACe road locomotives into a dual-fuel engine capable of running on CNG. In this case, a test locomotive would be paired with a tender unit housing CNG cylinders.
By using CNG to power long-distance locomotives, the railroad could achieve substantial fuel savings in addition to emissions reductions. A potential hurdle is the lack of CNG fueling infrastructure and the significant expense involved in constructing fueling stations and converting the fleet. In addition, moving beyond testing to actually using a CNG locomotive in service will require approval of the Federal Railroad Administration. Norfolk Southern, other railroads, and the FRA are discussing both liquid and compressed natural gas as alternative fuel sources for locomotives.
“Our primary interest in natural gas is the possibility of a reduced-emissions locomotive. A lot of municipalities concerned about exceeding federal clean air standards have expressed interest in this concept.”
manager locomotive engineering
Battery Work Breaks Ground
Norfolk Southern has done ground-breaking work in developing battery technologies for locomotives. Since beginning research around 2007, the railroad has received three U.S. design patents.
The latest patent was issued in February 2014. The patent covered the design of a hybrid road locomotive equipped with a regenerative braking system to capture and reuse dynamic breaking energy. One configuration calls for positioning a battery tender between two diesel-electric locomotives to store the captured energy and reuse it to power the locomotives’ traction motors, thus saving diesel fuel and lowering emissions. The traction motors, which generate pulling power, are used in dynamic braking on hilly terrain to maintain safe speeds. On conventional locomotives, the braking energy is blown off as heat through a resistor grid.
Partnerships Have Been Key
Norfolk Southern has received valuable assistance from industry, academic, and government partners in developing NS 999. Penn State University has provided lab support to evaluate the 999 battery systems. American Traction Systems has shared expertise in regenerative braking technology, and TMV Control Systems has been instrumental in developing onboard computer circuitry used to operate 999’s energy storage and traction control systems.
Recognizing the long-term payoff of developing affordable battery technologies for freight rail, the U.S. Department of Energy and the Federal Railroad Administration have provided grants to assist in research and development.
Norfolk Southern’s experimentation with battery-powered locomotives entered a new phase in early 2015, when a second-generation NS 999 prototype was put into service switching rail cars at the Roanoke, Va., Roadway Material Yard.
Sporting a fresh coat of distinctive green paint, the ecologically friendly 2.0 version features 864 advanced lead-carbon batteries and a new battery management system designed to address technical issues that had sidelined the original model, launched in 2009.
At the material yard, the 999 has worked with a diesel-powered switcher to support the yard’s track material recovery efforts. Among other duties, the yard serves as a large-scale recycling facility that daily recovers tie plates, rail anchors, and other track material from around the system for reuse.
The flat-switching yard, which operates a 10-hour shift, is an ideal working environment to expand the company’s expertise in battery technologies for train service. The 999, operated now by remote-control technology, is equipped with an onboard computer system that wirelessly transmits battery-performance data that employees in the company’s Research & Tests Department monitor from offices about five miles from the yard.
Overnight, the locomotive is plugged into a charging station. It also is charged up during a mid-day lunch break. The 999’s system of 12-volt lead-carbon batteries – which replaced 1,064 lead-acid batteries – generate pulling power equivalent to a 1,000-horsepower diesel engine. There have been glitches, but the 999 has proven capable. The best thing: It generates no emissions and virtually no noise when operating.
“It’s quiet; it’s clean; it’s a wonderful piece of equipment,” said Michael Wolfe, manager of the material yard.
Our research and tests employees continue developing a hybrid road locomotive powered by batteries and a fuel-efficient diesel engine.
Norfolk Southern collaborates with customers and business and industry partners on greener and cleaner ways to do business. Since 2010, Norfolk Southern has co-sponsored an annual Railroad Sustainability Symposium with GE Transportation that brings together railroad operators, manufacturers, shippers, and environmental stakeholders to discuss sustainable business practices.
In 2014, BNSF Railway joined to host the symposium in Fort Worth, Texas, at a two-day event that drew participants and speakers from more than 25 companies and organizations, including Maersk, UPS, Wal-Mart, the Worldwide Wildlife Fund, the Environmental Defense Fund, The Arbor Day Foundation, and the National Fish and Wildlife Foundation. Key discussion topics included supply-chain sustainability, innovative solutions to environmental challenges, and next-generation locomotives that continue to improve fuel-efficiency and reduce emissions.
The symposium’s focus is on sharing successes and creating an industry dialogue on ways to integrate sustainability into business operations.