Emulsified Diesel Emission Testing, Performance Evaluation and Operational Assessment; Project Extension to Examine an Ultra-Low Sulfur Diesel Fuel: TxLED

15. Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. 16. Abstract When TxDOT began using an ultra-low sulfur diesel fuel, Texas Low Emission Diesel (TxLED), they commissioned a simultaneous study of the effectiveness of the use of TxLED by both the TxDOT fleet and their contractors, the Associated General Contractors (AGC). Because TxLED is similar to conventional diesel fuel, there were no health or safety issues that had to be addressed in this study. The results from the full load torque curve tests and the operator assessments, together with the properties of TxLED compared to those for 2D on-road diesel fuel, indicate that there should be no performance penalties associated with use of TxLED. It was also found that, as expected, TxLED does not separate into lighter and heavier components over time and does not pose corrosion problems. For all engines tested, TxLED provided a statistically significant benefit in NOx emissions compared to 2D on-road diesel fuel. With the exception of only one engine, the NOx emissions benefits from using TxLED were higher than the benefits claimed in Texas’ State Implementation Plan. Additionally, statistically significant benefits in PM emissions were found for three of the six engines tested and small, but statistically significant, benefits in fuel consumption or fuel economy were found for three of the engines. Therefore, the cost-effectiveness of the NOx emissions reductions obtained with TxLED was the primary focus of this study. It is concluded that TxLED is a cost-effective strategy for reducing emissions from the TxDOT and AGC fleets. 17.