Last week, the Federal Transit Administration (FTA) announced that it will award King County Metro Transit (Metro) $4.7 million to purchase a prototype electric bus that runs on battery power.

Unlike Metro’s current fleet of electric trolley buses, these light-weight vehicles have the ability to operate without being connected to a fixed overhead wire. They can power up at a free-standing charging station and then travel up to 15 miles one way from the station. Metro will also explore if the prototype bus can connect to existing trolley wires for a "fast charge" when needed.

“This next generation electric coach combines the benefits of a clean, quiet trolley with the mobility of a standard bus,” said King County Executive Dow Constantine in thanking the FTA for the award. “If the prototype can work well here in King County, battery-powered buses could become an excellent candidate for replacement of aging Metro buses and trolleys. Not only would they cut diesel fuel costs, but they would also significantly reduce greenhouse gas emissions.”

Constantine said this grant marks another major investment in King County’s overall transportation system by the federal government. Earlier this month, the King County Department of Transportation received $34 million in federal money to top off funding needed to replace the South Park Bridge over the Duwamish River.

Metro’s prototype battery-dominant electric bus should be delivered in late 2012. The agency plans to buy one or two vehicles plus one or two charging stations to test their suitability for the transit system.

In addition to the battery bus demonstration, Metro is in the process of conducting a study to evaluate hybrid and trolley buses as replacements for the existing trolley fleet, which is reaching the end of its useful life. The study is examining several factors in choosing the vehicles to replace the trolleys, including cost; network and system considerations; environmental impacts; funding opportunities and legal issues. The study findings will help the county make an informed decision about the best technology to use on these routes as the current trolley buses wear out.

The trolley replacement study started last summer and does not include battery-dominant buses as an option because they are not yet available for a large-scale purchase nor tested on a system in the U.S. like Metro’s. At this time, the technology is not ready to replace heavy-duty transit vehicles, but is advancing rapidly.

The agency is also involved in projects to promote the private use of electric vehicles.

In addition to this grant, the FTA also awarded Metro and Sound Transit $6 million to purchase 40-foot and 60-foot hybrid diesel-electric buses to replace conventional diesel buses that have reached the end of their useful lives.