MD: Clean Diesel Buses to Power Maryland's Transit Future

Jan. 29, 2016
The Maryland Transit Administration is now in line to receive almost $100 million to invest in 172 advanced clean diesel buses after receiving approval by the state's spending board on Wednesday.

Jan. 29 -- The Maryland Transit Administration is now in line to receive almost $100 million to invest in 172 advanced clean diesel buses after receiving approval by the state's spending board on Wednesday.

The Baltimore Business Journal reported the new clean diesel buses will replace older vehicles – some which have been service for 15 years. 

"The Maryland Transit Administration made a strong and smart case for modernizing its bus fleet, and the choice for clean diesel buses is the best choice," said Allen Schaeffer, Executive Director of theDiesel Technology Forum.  "New clean diesels not only cost far less than other alternative powertrains, but are as clean – or cleaner – than alternatives. In this instance, the new clean diesels will reduce NOx and particulate matter by as much as 95 percent compared to the 10 or 15-year old buses they replace.

"Governor Larry Hogan has laid out a bold vision to increase the access, reliability and affordability of public transportation for Baltimore City residents.  This investment in new clean diesel technology ensures that this vision will be implemented with the latest and most advanced technology that will also deliver clean air and energy-saving benefits for everyone.

Diesel & Diesel Hybrid Buses Account for 75% of Public Transit Fleets

"Because of its combination of safety, reliability and efficiency, diesel is the predominant power source for public transit, school and intercity bus services nationwide," Schaeffer said.  Among publictransit agencies, Schaeffer said diesel and diesel-hybrid buses account for about 75 percent of the national fleet.

The Maryland decision mirrors other significant orders of clean diesel and diesel-electric hybrid buses by transit agencies in major communities like New York, San Francisco, Chicago, Detroit, and New Jersey. 

"In approving this expenditure, the Board of Public Works joins other major transit agencies around the country that are finding that clean diesel technology is the all-around best choice for public transportation from an economical and environmental perspective - it's more clean public transportation for the dollar," Schaeffer said.

EPA Regulations Have Virtually Eliminated Emissions from New Diesel Buses & Trucks

Schaeffer said diesel power systems have undergone revolutionary technological advancements that have already achieved dramatic reductions in emissions for urban buses and highway engines. Advances in emissions-control systems and ultra-low sulfur diesel fuel (ULSD), biodiesel and renewable diesel are helping clean diesel engines achieve emissions performance equivalent to compressed natural gas (CNG) and other alternatives, but without the costs and limitations of these technologies.

"Today, meeting EPA's clean air regulations means that engine manufacturers have virtually eliminated emissions by utilizing state of the art particulate filters and advanced selective catalytic reduction technology to cut smog-forming emissions to near zero levels," Schaeffer said.

Clean Air Task Force Emissions Study

Schaeffer said an analysis by the Clean Air Task Force illustrated the major emissions gains clean diesel buses have achieved. The analysis shows the air quality benefits of replacing older buses with newer clean diesel technology and a comparison of clean diesel and CNG buses.

2012 Clean Diesel Bus & 2012 CNG Bus Emissions Comparison
(Vs. Model Year 2000 Diesel Bus)

Vs. 2000 Diesel





2012 Clean Diesel




2012 CNG




(Source: Clean Air Task Force – "Clean Diesel versus CNG Buses: Cost, Air Quality & Climate Impacts")