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Ford USA have recently released a hybrid version of the popular
escape SUV. A hybrid car uses two or more means of power and in the
escapes case this comes from both a battery powered electric motor
and a petrol engine. The Escape Hybrid's electric motor is a compact
design that operates on power drawn both from the battery pack and
from a very intelligent generator motor. When required, the
generator motor restarts the gas engine (remember, the gas engine
shuts down automatically for stoplights and when coasting). And when
the gas engine is running, it helps recharge the battery pack.
That means in city or stop and go driving, you could spend a lot
drive time without using fuel. The ingenious generator motor
provides power boosts during heavy load situations, helping Escape
Hybrid accelerate briskly to speed. Aside from the fact that
electric motors use no fuel, they also deliver maximum torque at low
rpm so they are an ideal compliment to gasoline engines, which
generate best torque at higher rpm. And because Escape Hybrid's
power system is completely automatic, you never have to do a thing
except enjoy the ride and the fuel savings.
In a conventional vehicle when you brake, the energy is lost as
heat. During braking in the Escape Hybrid, the electric motor
captures this energy that is normally lost and sends it back to the
battery pack to be stored for later use. So when you apply the
brakes, you are, in effect, recharging the battery pack. Engineers
call this regenerative braking and it represents a major part of the
Escape Hybrid's fuel efficiency advantage over conventional
vehicles. Although Escape Hybrid will never make stop and go driving
any more enjoyable, that is actually when it is at it's fuel saving
best.
The Escape Hybrid's gasoline engine is a dual-overhead-cam design
with four valves per cylinder for optimum breathing and four-orifice
fuel injectors for fine atomization. It also incorporates a special
Atkinson cycle for improved efficiency. It works to slightly delay
intake valve closing to significantly increase the gasoline engine's
energy conversion efficiency. In other words: you get more mileage
out of each gallon of gasoline in an Atkinson cycle engine. The
four-cylinder engine is a well-proven design with three successful
years of service to its credit. In the Escape Hybrid, the Atkinson
cycle engine generates 133 horsepower at 6,000 rpm and 129 lb.-ft.
of torque at 4,500 rpm.
The Escape Hybrid is expected to be certified for sale as an
Advanced Technology Partial Zero Emissions Vehicle (AT-PZEV), the
strictest of emissions certifications. By itself, the Escape
Hybrid's 2.3L engine is very fuel-efficient. However, an innovative
stop/start function makes it even more so. The stop/start function
automatically shuts the engine down when it isn't needed such as at
stop lights, low speeds or when coasting. This puts the Escape
Hybrid at its fuel saving best in stop and go driving. The
stop/start cycling is completely automatic and seamless requiring no
driver input.
The sealed nickel-metal hydride (NiMH) battery pack in the Escape
Hybrid is rated at 330 volts. Its function is to store electrical
energy for starting the gasoline engine and for added boosts in
acceleration performance. Nickel-Metal Hydride batteries have been
used with excellent success for years. And because of regenerative
braking and the generator motor it's never necessary (or even
possible) to plug the Escape Hybrid into a charger.
When called upon, Escape Hybrid's battery pack also helps provide
fun to drive V-6-like acceleration or cruising at high speeds. Much
like a conventional vehicle, when you press hard on the accelerator
pedal of the Escape Hybrid, the VSC signals all the contributing
components to pitch in with their extra power. The Electric motor,
generator motor and battery pack all kick in to contribute and
combine their extra power with that of the gasoline engine.
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