Bus Technology Evaluation

In 2006, TransLink has completed Phase I of its Bus Technology & Alternative Fuels Demonstration Project. This study involved testing five alternative technologies against baseline diesel buses from TransLink's current fleet. The technologies tested were biodiesel, compressed natural gas, hybrid and near state-of-the-art diesel buses with EGR engines, which operated on ultra-low sulfur diesel fuel and were equipped with diesel particulate filters (Diesel+DPF). Results from the study will help us with future bus procurement decisions. Additional phases of the evaluation, testing emerging technologies, have been ongoing since 2006 and additional results will be made available as results are finalized.

Study Highlights

All of the tested bus technologies performed equal or better than the baseline diesel buses on the metrics of particulate matter, GHG emissions and fuel costs. However, some technologies had lower fuel economies and higher maintenance costs than the baseline buses.

Hybrid buses had the greatest fuel economy and the lowest fuel costs of all the bus types, with a 20% reduction in fuel consumption over the baseline diesel buses. The maintenance cost of hybrid buses is slightly higher than the maintenance cost for diesel buses, but is well below that for natural gas buses. Hybrid buses had significantly lower emissions of the tested propulsion technologies for all pollutants of interest, which include GHG emissions and ground-level air pollutants. The Diesel+DPF buses had the second lowest emissions of the tested propulsion technologies.

Results Summary

The table below is a summary of the results gathered from this project. Full details can be found in the Final Test Program Report.

Text-only version of the bus technology summary table...