The mass-market gasoline-electric hybrids made
by Toyota, Honda, and others make use of an electric engine
right under the hood next to the gas engine. That electric
motor creates fuel economy by kicking into use during idling,
backing up, slow traffic, and to maintain speed after the gas
engine has been employed for acceleration. The car doesn’t
need to be plugged in because the on-board electric battery
is constantly being charged by the gas engine and by the motion
of the wheels and the brakes.
The so-called “plug-in hybrids,” now in prototype
stages of development, take this technology a step further. By
adding the ability to charge up from a standard household outlet,
typically overnight, such cars relegate the gas engine to back-up
status and instead let the electric motor do most of the work.
Proponents claim that such “gas-optional” cars—if
you don’t take long trips you can rely entirely on the
electric motor—can be twice as fuel efficient as hybrids,
which already get double the gas mileage of traditional vehicles.
Additionally, they say, powering up plug-in hybrids with wall
sockets results in far less pollution (from the power plants
providing the electricity) than an equivalent gasoline-powered
car spews out its tailpipe. Meanwhile, plug-in hybrids recharged
from rooftop solar power systems might approach being the world’s
first mass-market “zero emission” vehicles, requiring
no power from the grid at all.
Convincing a skeptical American public that plug-in hybrids are
the way of the future is the challenge of a loose network of
advocacy groups led by the California Cars Initiative (CalCars).
Indeed, the experimental electric vehicles of a decade ago and
older required recharging every 25-50 miles, rendering them useless
for anything but short trips. The new breed of plug-in hybrids
solves this problem by employing much more sophisticated battery
technology while still keeping the insurance of gasoline (and
a gas engine) on-board.
It’s like having a second small fuel tank that you always
use first—only you fill this tank at home with electricity
at an equivalent cost of under $1/gallon,” reports the
CalCars Web site. The organization goes on to explain that with
gas prices at $3/gallon, traditional cars cost eight to 20 cents
per mile, while plug-in hybrids used for all-electric local travel
and commuting would cost only two to four cents per mile.
CalCars is lobbying the world’s major automakers to introduce
plug-in options on future hybrid models, and has built showcase
examples themselves that achieve 100 miles per gallon using Toyota’s
Prius. Meanwhile, a growing list of state and local governments
say they would seriously consider converting their fleets to
plug-in hybrids if such vehicles became available.
The Web site HybridCars.com reports that DaimlerChrysler has
built a handful of prototypes based on its 15-passenger Mercedes-Benz
Sprinter van. And analysts believe Toyota already has the technology
in place but may be waiting to gauge consumer demand before making
any production commitments. Only time—with a little guidance
from the price of gasoline—will tell.
CONTACT: California Cars Initiative (CalCars), www.calcars.org.
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