Government people tend to spend a lot of time thinking and planning when they should just get things done, contends David McCary, director of solid waste management for the City of San Antonio.
Bulky tanks for compressed natural gas consume room on a chassis, but there's usually room for them on trash collection trucks. Here the tanks are stacked vertically ahead of the packer body.  (Photo by Tom Berg)
Bulky tanks for compressed natural gas consume room on a chassis, but there's usually room for them on trash collection trucks. Here the tanks are stacked vertically ahead of the packer body. (Photo by Tom Berg)
That's why the Texas municipality's managers and elected officials have stopped studying what to do about vehicle-generated air pollution and have begun converting their trash trucks to burn natural gas.

"Government has a responsibility to lead by example and create a sustainable city," McCary told an audience during the Alternative Fuel Vehicle Institute's recent annual conference. "We get to make policy, and we should follow it" without undue delay. San Antonio, with a population of 1.34 million and 344,000 homes and businesses, needs cleaner air, and cleansing the exhaust of trash collection trucks is one way to do it.

"A lot of my colleagues are traveling around the nation seeing how many (diesel-powered) trucks they can buy before 2010" so they can beat higher purchase prices, he said. "That's not the answer."

The answer, he said, is to operate even cleaner-burning engines that are now available. They cost a lot more than diesel, but state and federal grant money is available.

Choosing CNG

McCary, who has managed fleets in other cities in the U.S., said he concluded that compressed natural gas was the best way to tackle the problem. The gas burns cleanly, and it's readily available in Texas, which financially encourages its use. Also, CNG stations are far less costly to buy and install than cryogenic liquified stations, which meant a system could be put into operation faster. He convinced members of the city council to go along with a 10-year action plan.

Helping to get the CNG program moving was San Antonio's political system, in which city council members serve two-year terms. That means they must quickly fulfill any promises they made during campaigning or they won't be re-elected, McCary explained. Clean air has been a political issue.

"While others were meeting and planning, we took action," he boasted. With the help of $1 million in grant money, the city opened its first CNG fueling station in July 2008 and began acquiring gas-burning trucks. It hopes to have 30 trucks running by the end of this year.

The gas-fueled trucks are proving less costly to operate than diesel. Because gas is subsidized, the city is saving 15 cents per equivalent-gallon of diesel. The city will encourage private haulers to switch to natural gas by offering discounted permits.

"You don't have time to sit still any longer," McCary told attendees at the conference in Orlando. "We have to act now... There are many vendors out there. All you have to do is raise your hand," and they'll come forward with information.

AT&T's Story

Another organization acting now is AT&T, which operates 85,000 vehicles. It announced it will spend $565 million for 15,000 alternative-fuel vehicles over 10 years. Included are $350 million for 8,000 CNG-fueled service trucks and plans for as many as 40 refueling stations, said Jerome Weber, vice president for fleet operations, another presenter at the alternative fuels meeting.

The new, cleaner trucks will amount to a small percentage of the total fleet, Weber acknowledged, but they'll contribute to cleaner air. Last year AT&T's 105 alternative-fuel and hybrid vehicles cut carbon dioxide emissions by 30 percent.

AT&T chose CNG for California, where an infrastructure is in place and increasingly strict anti-pollution regulations demand using it. Generally, CNG costs 30 to 40 percent less than unleaded gasoline and also less than liquified natural gas. Most CNG comes from domestic wells and is reliably supplied via pipeline, Weber and other users said.

Experience with CNG will help when hydrogen fuel cells come into use, Weber said, as natural gas is the likely fuel for the cells, which are still under development.

Service life for an AT&T truck is 10 to 12 years, allowing time for return on investment. Higher vehicle purchasing costs are somewhat offset with real paybacks: CNG-powered vehicles get 22 to 30 percent better fuel economy, while new and converted hybrids save 44 to 56 percent in fuel, he said.

From the June 2009 issue of Heavy Duty Trucking.