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Name: Keith F.
Status: Student
Age: 30s
Location: N/A
Country: N/A
Date: July 2004

What do you see as the next step towards mass transportation in regard to hybrid vehicles?

I am not sure about Europe and Asia, but in the United States, General Motors is currently producing diesel-electric hybrid buses that were use in Houston, Portland, Austin, Salt Lake City, Hartford, Newark, and Orange County, California as of January 2004. King County, Washington, which includes the Seattle area, ordered 230 hybrid buses in October 2003.

Diesel-electric locomotives have been around for 70 years, so hybrid technology in mass transit is nothing new. Unlike the new generation of hybrid cars and buses, though, locomotives do not recover and store the energy from braking in batteries to help provide motive power. But, this is less critical because locomotives are not stopped and started as often as buses are.

While hybrid technology makes sense for vehicles used primarily in stop-and-go driving, like buses, taxis, and delivery vehicles, I personally think that it is an inelegant solution for most people. Hybrids have to have two drive systems and large battery packs, making them expensive and heavy. The hybrid system provides little or no benefit when driving on the open road at a constant speed, which is why they achieve lower fuel economy on the highway than in town. Many, if not most, hybrid owners report that their new cars do not achieve the EPA fuel economy ratings in most real-world driving and the EPA is considering revising its fuel economy ratings to be more realistic for modern cars.

A lighter, simpler car with a turbocharged diesel engine can achieve fuel economy and performance as good as or better than current hybrids at less cost using technology that is mostly well-proven. The catch with diesels is that they produce invisibly small particulates in their exhaust that may be harmful to human health. However, research into controlling these emissions is promising and a solution to this problem is expected before the end of the decade. Since I live in a medium-sized city without significant traffic problems and my daily commute is ten miles, has only three traffic signals, and is conducted mostly on a free-flowing expressway at 60 to 80 mph (depending on how late I am to work), a diesel makes much more sense in the near term for people like me.

Andy Johnson

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