Management & Operations

CARB study measures CNG, diesel bus emissions

Posted on May 1, 2002

Study results released in April by the California Air Resources Board (CARB) assert that buses running on both compressed natural gas (CNG) and ultra-low-sulfur diesel fuel, with the proper emission controls in place, can attain significant reductions in toxic emissions. The testing, which was conducted from March 2001 to June 2001, compared exhaust levels of a diesel transit bus equipped with emission control technology to another diesel bus and a CNG bus that had no particulate filter or after-treatment equipment. Test results confirmed that CNG buses emit lower levels of particulate matter and nitrogen oxide than diesel fumes. However, information gathered in the study also demonstrated that the level of some toxic pollutants given off by CNG buses can be substantially higher than those found in “clean diesel” fumes. The study produced favorable results for diesel buses using a particulate filter. The diesel bus running on ultra-low-sulfur fuel had lower emissions than the unequipped diesel and CNG buses in the amount of toxic organic compounds and total mass of particulate matter. “When the diesel bus was retrofitted with a trap and run on low-sulfur fuel, its performance was very promising,” said Dr. Alan Lloyd, chairman of CARB. “We are working now to obtain better performance from CNG buses when they are equipped with state-of-the-art after-treatment equipment.” Currently, tests are being conducted using CNG buses with new manufacturer-installed oxidation catalysts. Results of those tests will be released in mid-2002. A joint statement from several organizations in response to CARB’s results claimed that the study’s comparison of buses was unfair because the CNG bus tested was not equipped with the most up-to-date clean-air technology. The statement did offer an endorsement by the groups of the perceivable improvements in diesel fuel emissions as well as CARB’s efforts to improve bus emissions. The organizations that drafted the statement include the American Lung Association, Coalition for Clean Air, Natural Resources Defense Council, Planning and Conservation League, Sierra Club and Union of Concerned Scientists.

View comments or post a comment on this story. (0 Comments)

More News

Pace mourns death of Bolton, former deputy exec. director

He passed away in the early hours of April 15, 2017, after battling pancreatic cancer. He was 69.

CATA CEO Draggoo announces plan to retire

She is currently the longest-serving transit CEO in the nation. Her career with the authority spans 43 years, 32 of them as CATA’s CEO.

FTA taps nonprofit to lead mobility-on-demand innovation project

The initiative, which will be lead by the Shared-Use Mobility Center, will focus on helping recipients of FTA’s Mobility On Demand Sandbox program funding demonstrate innovative transportation solutions in 11 cities across the U.S.

WMATA to add free Wi-Fi at 30 rail stations

If plans stay on track, nearly every Red Line station from Union Station to Medical Center will have access to free Wi-Fi and a broad section of the system’s core also should be covered by the end of the year.

METRO, BusCon now accepting Innovative Solutions Award submissions

Applications can be submitted either by the operation or the solutions provider and will be judged by our BusCon Advisory Board, with winners and shortlisted submissions recognized at BusCon’s Award Breakfast on Wednesday, Sept. 13.

See More News

Post a Comment

Post Comment

Comments (0)

More From The World's Largest Fleet Publisher

Automotive Fleet

The Car and truck fleet and leasing management magazine

Business Fleet

managing 10-50 company vehicles

Fleet Financials

Executive vehicle management

Government Fleet

managing public sector vehicles & equipment

TruckingInfo.com

THE COMMERCIAL TRUCK INDUSTRY’S MOST IN-DEPTH INFORMATION SOURCE

Work Truck Magazine

The number 1 resource for vocational truck fleets

Schoolbus Fleet

Serving school transportation professionals in the U.S. and Canada

LCT Magazine

Global Resource For Limousine and Bus Transportation

Please sign in or register to .    Close