Although it is good to be
the first to think up a new technology, it's probably even better
to be the first to implement it. Toyota has done just that, buy
mass-producing -- for the second time -- a hybrid and electric passenger
car. Nargess Shahmanesh-Banks went to see if the second-generation
Prius has what it takes to crack the eco-friendly market.
The 2004 Toyota Prius will pave the way for a more manufacturers to invest in alternative fuel cars |
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"We think that hybrid has huge potential," says Dr Shiseyuki
Hori, executive chief engineer at Toyota and in charge of the Prius
project. He admits that the initial investment was colossal as absolutely
all R&D was carried out in-house. However he admits that this
strategy has been fundamental to the development of the second-generation
model. Additionally, the new car doesn't share any common platform
and almost no common parts with other Toyota products, explains
the hybrid project general manager, Katsuhiko Hirose.
The car is off course designed primarily to be the world's cleanest
family car and at 65.7 mpg combined fuel consumption and 104g/km
of CO2 emissions, it lives up to this promise. It is also fuel efficient,
covering more than 600 miles on a single tank of fuel. It produces
the lowest NOx and HC emissions of any internal combustion production
car in Europe and meets comfortably not just Euro IV, but Japan
and US J-ULEV and AT-PZEV emission regulations at the same time.
And last, but not least, it is the also easier to dismantle for
end-of-life purposes.
The reason for such improvement from the old model is Toyota's self-made
Hybrid Synergy Drive (HSD) technology, which has created one of
the most powerful electric motor for its weight and size. Current-generation
hybrids rely on the petrol engine to produce peak performance, with
the electric motor as an ancillary. HSD, on the other hand, gives
the electric motor a more significant role.
"This technology makes it possible to reach whole new territories
in the automotive field, allowing a total repositioning of the hybrid
vehicle from an 'eco-friendly car' to a 'fun to drive machines',"
says Hori.
The problem is that the driver today, no matter how green minded,
still expects some degree of performance from a modern car. HSD
delivers just that. A more powerful 1.5 litre petrol engine works
together with a smaller, more efficient electric motor to deliver
performance. At 400Nm from 0-1200rpm, 0 to 62mph acceleration falls
below 11 seconds. It's a smoother drive as the hybrid's advanced
control system uses the electric motor as the main power source.
Additionally noise and vibration have been reduced, although this
is less apparent at higher high speeds.
Also new is something called the EV (Electric Vehicle) button, which
essentially mean that when pressed it allows the driver to select
full electric mode, which comes in very handy when stuck in city
traffic. The frustration is at least somewhat subdued knowing that
you are delivering zero emissions.
Other new technology includes a high voltage power circuit that
supports the HSD. The circuit inside the power control unit helps
both the motor and generator's voltage to be increased from 274V
in the original Prius to a maximum of 500V in the new model. The
high voltage power circuit increases power by upping the voltage
from 202V to a maximum of 500V while keeping the current constant.
Electrical power can be supplied to the motor by using a smaller
current, thereby contributing to increased efficiency. Although
the battery voltage is lower than that of the previous model, a
new converter boosts the total system voltage to 500V when in use.
Additionally, Toyota has been able to increase power supply by 1.5
times over the original Prius from 33kW to 50kW, even though the
motor hasn't increased in size.
Hirose calls the shape: "Triangular Monoform." It is definitely
a larger car from all angels and at 4450mm long, it is 135mm longer
than its parent model. "This is because of aerodynamic packaging,"
Hori explains. Inside is roomy and subtly modern. It is meant to
create the same atmosphere as a modern living room, says Hori.
Although a much more forward looking car in terms of design than
the old one, you get the feeling Toyota stopped short at some point.
This is no surprise, after all the car will be revolutionary in
concept for the average consumer, therefore to go all the way in
terms of styling too, may have alienated all interested but the
true avant guard.
The first generation Prius sold more than 130,000 worldwide since
its launch in 1997. And the new five-door hatchback, branded in
the D-segment and selling at the same price as diesel models in
its class, hopes to beat this record. Sales in Europe are expected
to be around 5,000 and 76,000 worldwide by 2004. According to reports
from Japan, so strong is demand for this Prius that Toyota is seriously
considering a third shift at its Tsutsmi factory in Toyota. Sales
are running at double anticipated volumes and the idea is to lift
monthly output from 6,000 units per month to 10,000.
The Prius project may be a technology showcase for Toyota, as Hirose
points out, but it also a true testimony as to how far technology
has come, and how much further it is able to go, if pushed. Perhaps
one way to 'sex-up' hybrid would be to install it in a less accessible,
less practical, sportier car: the Toyota CS&S concept perhaps?
No doubt, other carmakers will follow suite, but it would be interesting
to see if the first one in can keep ahead in the fast lane.
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