Pierce Transit buses gas up from landfill



Tacoma — The wheels on the bus for Pierce Transit are now powered by natural gas from a King County landfill.

Pierce Transit has become the first bus system in the country to switch to renewable natural gas as its primary fuel source.

Natural gas from the Cedar Hills Regional Landfill in Maple Valley is fueling 143 buses that had been powered by fossil natural gas. The renewable natural gas is refined from the landfill and purchased from Puget Sound Energy.

“It seemed like the logical next step for Pierce Transit,” said Chief Executive Officer Lynne Griffith. “It’s a continued commitment to environmentally friendly fueling technology.”

Pierce Transit started using compressed natural gas in 1986. That is fossil natural gas extracted from underground rock formations.

Renewable natural gas is derived from the decomposition of organic waste at the landfill.

Some of the agency’s vehicles are not affected by the change: About 10 percent of Pierce Transit’s buses are diesel-electric hybrids, and the system’s shuttle vans are fueled by gasoline.

Scott DeWees, project manager for Western Washington Clean Cities, said Pierce Transit is the first fleet of any kind in the state and the first transit system in the country to switch to renewable natural gas as its main fuel source.

The biggest benefit is reducing greenhouse gases by 80 percent, DeWees said. That reduction takes place by avoiding the need to refine and use traditional natural gas, he said.

The Clean Cities program is a program of the U.S. Department of Energy.

Pierce Transit made the switch in June an announced it last week.

The mileage is the same and the change didn’t require new equipment at Pierce Transit’s fueling station in Lakewood where the natural gas is compressed, said Bill Spies, senior manager of maintenance.

“It’s just like buying a different kind of gasoline,” Spies said.

The tailpipe emissions are also the same, DeWees said.

The cost for the two types of natural gas is virtually identical. The agency says it will receive about $12,000 a year in rebates from Puget Sound Energy because of the switch.