The test is UP's latest effort to further reduce emissions and move closer to the U.S. EPA's Tier 4 locomotive emissions standards for new locomotives starting in 2015, the railroad said in an announcement Monday.
The locomotives are intermediate line-haul units, with an operating range of approximately 200 miles, and will be used exclusively in California.
"The testing and analysis of these locomotives is part of an ongoing initiative at Union Pacific to develop and use technology in pursuit of emissions reductions," said Mike Iden, UP's general director, car and locomotive engineering. "This effort is emblematic of our continued commitment to provide environmentally responsible freight transportation."
One locomotive based in Roseville to test the combined use of exhaust gas recirculation (EGR), diesel oxidation catalyst, and diesel particulate filtering. "In testing the combined benefits of these three technologies on one freight locomotive, this Union Pacific unit is the closest an Electro-Motive Diesel locomotive has come to achieving Tier 4 standards," said UP. "The move toward Tier 4 is made up of a 45% reduction in the oxides of nitrogen emissions compared to the current Tier 2 standard and an 85% reduction in particulate matter emissions based on preliminary analysis."
Nine of the experimental units fitted with the EGR technology are to be based in the Colton, Calif., area and will be tested through operations in the southern California region.
The remaining 15 experimental units will work out of Roseville for operations in northern California. These locomotives have the capability to be retrofitted with EGR and other emissions reduction technologies as testing progresses. The Proposition 1B – Goods Movement Emission Reduction Program is partially funding this set of locomotives.
Testing on all 25 locomotives is scheduled to last through 2014.