A Tale of Quiet Efficiency: How Hybrid Buses Are Benefitting the Environment and Reducing Financial Costs for King County Metro
H O Ferguson, J Ritchie, Stoel Rives LLP, US
This paper analyzes Metro’s experience with hybrid buses during the past decade and forecasts the impact of increased use of hybrids in the years to come.
King County Metro is a local government agency that provides public transit service to more than 100 million riders annually in the metropolitan area of Seattle, Washington (USA). In 2002, Metro put its first hybrid (diesel-electric) bus into service. Since that initial run, Metro has expanded its use of hybrid buses, which now comprise more than 42 percent of Metro’s entire fleet of about 1,300 vehicles.
With the increased use of hybrid buses, Metro and the population it serves have realized substantial environmental and financial benefits. Environmentally, both carbon and diesel particulate emissions have dropped considerably as hybrid buses have replaced diesel-only vehicles. Metro has also achieved a corresponding drop in noise pollution along urban and suburban routes. Financially, Metro’s fuel costs have dropped substantially, and maintenance costs also have dropped because of the increased reliance on simple-design motors and braking systems.
As a result of these benefits, Metro plans to increase the number of hybrids in its fleet. This paper analyzes Metro’s experience with hybrid buses during the past decade and forecasts the impact of increased use of hybrids in the years to come.
Association for European Transport