The King County Washington transit system was one of the first in the United States to start widely using hybrid buses and they just announced a major expansion of the effort. Since King County got their first hybrid buses over three years ago they have put 214 of them on the road. In the fall of 2006, voters approved a twenty percent expansion of the transit system services and today King County executive Ron Sims announced that they have decided to purchase up to five hundred more articulated buses from New Flyer Industries with the GM-Allison two-mode hybrid system.

Since putting their first hybrid buses into service King County has measured a thirty percent reduction in greenhouse gas emissions from the hybrids compared to their conventional buses and forty percent better reliability. The first twenty-two buses for the service expansion are expected to arrive next spring with another one hundred in 2009. Over the next five years the additional buses will be purchased to replace older conventional buses in the fleet.

In King County's experience so far the hybrids have gotten over 4mpg compared to about 3mpg for conventional diesel buses and they are expected to last 14-16 years compared to twelve for the non-hybrids. The powertrains could potentially last up to twenty years but the bus itself begins to wear out in the shorter time-frame. So far their are over seven hundred GM hybrid buses on the road in fifty-six cities and they've accumulated over 35 million miles. The press release is after the jump.

[Source: General Motors and King County]
Historic King County Contract Includes GM Hybrid-Powered Buses
Contract may increase fleet to more than 700 GM-hybrid powered buses, saving an estimated 1.1 million gallons of fuel annually, enough to fill 138 tanker trucks

SEATTLE – King County awarded a landmark contract today for the purchase of up to 500 articulated buses, most of which will be powered by General Motors' 2-mode hybrid system.

The five-year contract, which could be worth as much as $400 million, is between King County and bus-manufacturer New Flyer Industries. General Motors supplies New Flyer with the hybrid system for the buses.

King County has been operating a fleet of 214 GM hybrid-powered buses since 2004 and with the addition of this contract, King County could have a total of 714 buses, making it the largest fleet of hybrid-articulated buses in history.

King County Executive Ron Sims welcomed key local and national transportation leaders and representatives from GM and New Flyer, as they announced the contract agreement during a press conference today at Qwest Field, home of the NFL's Seattle Seahawks.

"It's innovative public-private partnerships such as this that put King County in a leadership position to combat global warming," said King County Executive Ron Sims. "We will put new rapid transit bus service on the streets with the first 122 articulated hybrids ordered. The size of this contract demonstrates our commitment to transit and the resulting benefits to our residents for air quality and traffic congestion."

King County's efforts to reduce greenhouse gas emissions and target global warming are among the most aggressive in the U.S.

Due to this strong environmental leadership, King County has one of the greenest transit agencies in the nation and GM is proud to supply its advanced hybrid technology to assist in this achievement.

In the U.S., GM's strategy is to save as many gallons of fuel as possible by applying hybrid technology first to larger vehicles such as mass transit buses. Currently, 720 buses with GM's 2-mode hybrid system have been delivered to 56 cities across the U.S. and Canada, saving an estimated 1 million gallons of fuel annually. The potential addition of up to 500 buses in King County, will bring the total in North America to more than 1,200 GM hybrid-powered, saving an estimated 1.75 million gallons of fuel annually.

"We at General Motors share King County's vision to reduce oil consumption and greenhouse gas emissions," said Tom Stephens, GM Group Vice President, Global Powertrain and Global Quality. "GM's commitment to improving fuel economy, reducing vehicle emissions, and developing electrically driven vehicles is not a short-term strategy. We're in this game for the long term. We see energy and environmental leadership as a critical element of GM's ongoing turnaround plan and a key part of our business strategy. That is why we are introducing four all-new hybrid models in 2007, which is more than any automaker has ever introduced in one calendar year."

Transit buses with GM's 2-mode hybrid system deliver significantly better fuel economy than traditional transit buses, cut certain emissions up to 90 percent and have operating sound levels approaching that of passenger cars. Other benefits of GM's 2-mode hybrid system for transit buses include reduced maintenance costs resulting from extended brake, engine oil and transmission oil life, superior torque, and improved acceleration.

In fact, the National Renewable Energy Laboratory (NREL) conducted a one-year comparative study between conventional diesel buses and GM hybrid-powered buses operating on a typical King County drive cycle.

The NREL report showed that the GM-hybrid powered buses had 30 percent higher fuel economy on average when compared to the conventional diesel buses and total operating costs were lowered by 15 percent.

During King County drive cycle testing, the NREL results showed that the GM-hybrid powered buses lowered fuel consumption by 23 percent; nitrogen oxides (NOx) by 18 percent; carbon monoxide (CO) by 60 percent; and total hydrocarbon (THC) by 56 percent when compared to conventional diesel buses.

This NREL study of King County's hybrid buses is an endorsement of GM's 2-mode hybrid propulsion system and one element of King County's decision to purchase up to 500 additional buses. The report was published in December 2006, and can be viewed at

To represent emissions reduction and King County's purchase of up to 500 hybrid buses, GM is donating up to 500 trees that will be planted throughout the county this year. The first five trees will be planted in a historic portion of Marymoor Park located in Redmond, Wash., that was heavily damaged by a November windstorm.

The 2-mode hybrid technology in these buses has served as the starting point for GM's co-development with DaimlerChrysler and BMW Group of the 2-mode hybrid system for passenger vehicles, which GM will launch later this year in the Chevrolet Tahoe and GMC Yukon fullsize SUVs, followed in 2008 by the Cadillac Escalade fullsize SUV, Saturn Vue Green Line compact SUV and the Chevrolet Silverado and GMC Sierra fullsize pickups.

"The Chevrolet Tahoe and GMC Yukon are the world's first and only fullsize hybrid SUVs, offering up to eight-passenger seating and an estimated 25 percent improvement in overall fuel economy when combined with our Active Fuel Management cylinder deactivation technology," said Beth Lowery, Vice President, Global Public Policy and Government Relations.

The 2-mode hybrid diesel-electric drive system for transit buses is manufactured by GM Allison Transmission, maker of transmissions and hybrid propulsion systems for commercial trucks, buses, and off-highway equipment and military vehicles, headquartered in Indianapolis.

New Flyer is based in Winnipeg, Manitoba.

General Motors Corp. (NYSE: GM), the world's largest automaker, has been the annual global industry sales leader for 76 years. Founded in 1908, GM today employs about 284,000 people around the world. With global headquarters in Detroit, GM manufactures its cars and trucks in 33 countries.

In 2006, 9.1 million GM cars and trucks were sold globally under the following brands: Buick, Cadillac, Chevrolet, GMC, GM Daewoo, Holden, HUMMER, Opel, Pontiac, Saab, Saturn and Vauxhall. GM's OnStar subsidiary is the industry leader in vehicle safety, security and information services. More information on GM can be found at

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