Measurement of the Energy Use and Emissions of Passenger Rail Locomotives Using a Portable Emission Measurement System

The purpose of this study is to demonstrate methodology for in-use measurement of dieselelectric passenger railroad locomotives using a Portable Emission Measurement System (PEMS). The methodology was developed and demonstrated based on railyard load tests of three locomotives, including one GP40 and two F59s. These locomotives have mechanically governed prime mover engines ranging from 140 to 169 liters displacement and with 3,000 hp output. Each locomotive also has a “head-end power” (HEP) engine of 19 to 27 liters that produce approximately 600 hp. The engines were measured using ultra-low sulfur diesel (ULSD) fuel. In collaboration with the locomotive owner and operator, including the field mechanics, we developed fittings and protocols for instrumenting the engines in order to measure manifold absolute pressure (MAP), engine RPM, intake air temperature, and exhaust concentration. Prime mover engines are operated at throttle notch settings. For the HEP engines, three different electrical loads were applied for a period of approximately 10 minutes each based on power usage for one, two and four passenger cars, respectively. Over 97 percent of the raw data survived a multi-step quality assurance process. The data obtained from the PEMS for the main engines were found to be comparable, on a fuel-basis, to data reported by others, particularly for NOx and CO. The key results from this work are establishment of a methodology for future tests and development of baseline data. The tested locomotives are planned for major overhauls in order to reduce emissions in compliance with current standards. There are also plans to switch these locomotives from ULSD to soy-based B20 biodiesel. The current work establishes a baseline for comparisons of these planned changes.