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Regional Transportation District Biodiesel Buses

The Fleet Test and Evaluation and Nonpetroleum Based Fuels teams worked with the Regional Transportation District in Boulder, Colorado, to evaluate nine 40-ft Orion V transit buses equipped with Cummins Westport ISM engines. During the 2-year evaluation, five of the buses were fueled with B20, while the remaining four ran on petroleum diesel.

Headquartered in Denver and located at a mile above sea level, the Regional Transportation District operates and maintains a fleet of more than 1,000 buses serving the needs of about 2.6 million people.

The results of this study are featured in 100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20).