2021 journal article
Multi-scale evaluation of diesel commuter rail fuel use, emissions, and eco-driving
TRANSPORTATION RESEARCH PART D-TRANSPORT AND ENVIRONMENT, 99.
Diesel commuter rail emissions affect populations near rail corridors. An approach is demonstrated to quantify mesoscale and microscale diesel commuter rail fuel use and emission rates (FUERs) of CO2, CO, NOx, particulate matter, and total hydrocarbons based on two U.S. systems. A speed trajectory simulator, an energy model, and an emissions model were calibrated, evaluated, and applied. FUERs and potential reductions from eco-driving were quantified based on simulated trajectories. Hotspots were defined as sections with β₯ 90th percentile of section-average FUERs by species. A few key variables explain 74β80% of variability in mesoscopic and microscopic FUERs. On average, FUERs are 7β8 times greater for hotspots than non-hotspots. Eco-driving was estimated to reduce segment-average FUERs by 3β33% and eliminate 2β11% hotspots. However, mesoscale oriented eco-driving can, at some locations, increase microscopic FUERs. The approach is adaptable to other diesel commuter rail systems.