Greyhound Lines Inc.'s buses are one of America's icons, serving over 3,700 destinations in the U.S, Canada and Mexico.

The once-famous bare-metal livery may have disappeared in the last few decades, but over 25 million passengers still use the services every year--making improvements to the company's fleet a high priority.

To this end, Greyhound's recent order for 220 new clean diesel buses--its biggest order in 20 years--should have a significant effect on the fleet's environmental impact.

Two companies, Motor Coach Industries and Prevost of the Volvo Group, will supply the new buses. Thanks to tight EPA emissions regulations for larger vehicles, the new buses produce 98 percent fewer NOx emissions (oxides of nitrogen) and particulate matter than their equivalents from 25 years ago.

Advancements in both engine technology and the use of cleaner fuels--such as ultra low sulfur diesel--mean diesel buses now match the emissions performance of traditionally cleaner natural gas (CNG) buses. Diesel is still an important consideration for bus operators, since diesel buses are 20 to 25 percent less expensive than their CNG equivalents.

It isn't just newer buses contributing to Greyhound's greener fleet--upgrades to older diesel engines are still able to cut emissions from existing buses in the fleet by 90 percent.

“Because of these major advancements, clean diesel buses offer significant operational advantages over many alternative fuels, and assure reliable, durable, and cost-efficient bus transportation" explains Allen Schaeffer, executive director of the Diesel Technology Forum.

Diesel's wide availability makes it a more practical fuel for wide-ranging bus fleets like those from Greyhound, even if the fuel itself currently costs more than CNG.

The new fleet additions and improvements to the old fleet continue to make Greyhound's service not just cost-effective, but better for the environment, too.


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