Last week, GE rolled out the cleanest and most fuel-efficient freight locomotive since it started making train engines a century ago. The engine is a prototype for a new GE Evolution Series locomotive. It meets the Environmental Protection Agency’s strict, new “Tier 4″ emissions standards, which slash particulate emissions limits by a whopping 70 percent and oxides of nitrogen (NOx) emissions by 76 percent, compared to the current production engines.
Cinders and Ashes!: The new locomotive is GE’s cleanest and most fuel efficient freight train engine. It will be made GE workers in Erie and Grove City, Pennsylvania, and Fort Worth, Texas.
GE invested $400 million in the new locomotive and set aside another $200 million for testing. Omowoleola “Wole” Akinyemi, manager of the internal combustion lab at GE Global Research was one of the 6,000 GE engineers, researchers, designers and machinists who spent the last five years developing the locomotive. “We were facing two big questions,” Akinyemi says. “We could reduce emissions at the exhaust level, like in a car fitted with a catalytic converter, or solve the problem inside the engine cylinders.”
A common way to scrub NOx from diesel engines involves the chemical urea (also used as a nitrogen source in fertilizers). The additive reduces oxides of nitrogen to form nitrogen and water. The process is simple but also expensive. Customers would have to spend some $2 billion in infrastructure upgrades to supply their engines with enough urea to meet the new standards. “They are used to dealing with diesel.” Akinyemi says. “They’d have to come to terms with urea fairly quickly.”
The GE team wanted to do better. It redesigned the entire engine to achieve cleaner, lower temperature diesel combustion and less NOx.
That’s easy to say, but a GE locomotive engine is multi-ton behemoth sporting 12 or 16 massive cylinders. Akinyemi and his global team of 20 researchers in New York, Munich and Bangalore had an idea. They developed new combustion system designs, studied them inside a single cylinder test engine and took detailed measurements of exhaust levels, temperature and other data. Then they fed the information to sophisticated computer models and simulations and extrapolated the results from a to a full scale engine. “It was critical that we knew that our solution met the target before we went to the real engine,” Akinyemi says. “With the single cylinder experiments we were able to isolate the combustion process. When we built the full-scale engine, the results were very close.”
GE estimates that the new locomotive, which is packed with a new turbocharger, fuel injection, exhaust system, and other advanced technologies, will save its rail customers billions without giving up any of the performance of the 5,000 ecomagination-qualified Evolution Series locomotives, which now pull freight around the world. The engines that already move one ton of freight more than 480 miles on a single gallon fuel just got more powerful.