Next Vehicle Design
Name: Keith F.
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
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.
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Update: June 2012