The Evergreen Fleets program is patterned on the Leadership in Energy and Environmental Design (LEED) Green Building Rating System, which certifies the energy efficiency of buildings. It ranks participants on a five-point scale for steps taken to curb emissions by fleets of vehicles operated by private companies and government agencies.

“If all of the fleets in the Puget Sound region became four- or five-star, it could reduce a half a million metric tons of CO2 a year,” said Evergreen Fleets Project Director Lesley Stanton.

The program, a collaboration between the Puget Sound Clean Air Agency and the Puget Sound Clean Cities Coalition, targets fleets because half of the greenhouse gases released in the Puget Sound region are from vehicle operations, and a “substantial portion” of those gases are from public and private fleets, Stanton said.

The system rates fleet operators on emissions reduction while providing incentives to reduce more. “The idea is continuous improvement,” Stanton said. Participants can “start any time and they can work their way up” in a system that “has some rigor in it.”

Launched in August, the program has 46 members and will start charging for memberships Nov. 1, Stanton said. So far the City of Mercer Island and Snohomish County are certified. (Snohomish County got a three-star rating, while Mercer Island got one star.)

The idea of the program forming the “foundation” for a national standard evolved in recent months, as the founders realized they’d created a certification approach that exists nowhere else, Stanton said. It’s unclear how the approach could be expanded.

Snohomish County Fleet Manager Allen Mitchell, who oversees 1,400 vehicles, said the program is “like a cookbook” for cuting emissions. “There are all these methodologies fleets can look at and adopt, and find their ways to reach these goals,” he said. For instance, the program is helping the county avoid buying high-emission vehicles when smaller ones can do the job.

The county has retrofitted 132 trucks with emissions-reducing devices, and has converted some Toyota Priuses into plug-in hybrids, he said. Stanton said the goal is for Evergreen Fleets to gain 300 fleet-operator members by the end of the year, with up to 40 fleets certified.

Seattle is undergoing certification for its fleet of 4,000 vehicles, and hopes to win four stars. Certification can have public relations value, said Chris Wiley, who coordinates the program for the city. The program is helping Seattle go beyond its current efforts. For instance, while the city has bought hybrid vehicles, it is now paying more attention to driver training, another aspect of the certification process, on such details as deliberate acceleration, reducing idling and braking tactics specific to hybrid vehicles.

“Driver behavior influences miles per gallon more than anything...that’s a place we haven’t focused until now,” Wiley said.

Other cities seeking certification include Lynnwood, Everett, Kent, Kirkland, Bellevue, and farther away, San Antonio, Texas. A few private-sector operators also have joined, including Avista Corp. and Pacific Electric Vehicles.