The new Jetta Hybrid has made
its world debut at the North
American International Auto Show
in Detroit, bringing electric
drive to a new class of
Volkswagen. Propulsion comes
from a high-tech 1.4-litre TSI
150 PS petrol engine and a 20 kW
zero-emissions electric motor.
Together, these provide not
merely fuel consumption that is
around 20 per cent better
overall than an equivalent
petrol-powered vehicle (at 45
mpg US – around 54 mpg
Imperial), but also sporty
performance, with the benchmark
0 to 60 mph sprint taking less
than nine seconds.
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Like the Touareg Hybrid, the
Jetta is a parallel hybrid,
using a decoupling clutch that
can disengage the petrol motor
for pure electric drive (or when
coasting or braking), disengage
the electric motor (for higher
speeds or when the battery
charge is low), or combine the
two units for maximum power.
Using electric power alone, the
Jetta Hybrid can be driven at
speeds of up to 70 kmh (44 mph)
and over a distance of two
kilometres (1.3 miles),
depending on conditions. For
maximum performance, both the
TSI engine and the electric
motor combine, giving peak power
of 170 PS. This is the first
use of the 1.4-litre
turbocharged engine in America,
and it offers the same power and
more torque (250 Nm, 184 lbs ft)
than the normally aspirated
2.5-litre engine that is
commonly used in the Jetta
there. |
A
lithium-ion battery supplies the
energy for the electric motor.
It is located behind the rear
seat bench, making no
compromises on interior space.
The battery is made up of 60
individual cells, each with an
energy capacity of five Ah.
Together they produce a nominal
voltage of 220 Volts and an
energy capacity of 1.1 kWh and
weigh 38.5 kg. Cooling is
provided by an integrated fan,
operated by the battery’s own
management system that performs
diagnostic, monitoring and
safety functions, including
disconnecting the battery in the
event of an accident.
Power is directed to the front
wheels via a seven-speed dual
clutch DSG gearbox, which is
efficient and lightweight, at 74
kg. Despite the extra weight of
the battery, electric motor and
extra safety modifications to
the vehicle’s structure, the
Jetta Hybrid weighs only 100 kg
more than the non-hybrid Jetta
at less than 1,500 kg in total.
Provided the battery contains
sufficient charge, the Jetta
Hybrid is switched to electric
drive mode either automatically
(at speeds of up to 60 kmh or 37
mph) or at the press of a button
next to the gear lever (up to 70
kmh or 44 mph).
When the driver releases the
accelerator pedal at higher
speeds (up to 135 kmh or 84 mph)
the TSI engine is decoupled,
reducing drag torque losses, and
maximising fuel efficiency.
Under braking, the Jetta Hybrid
switches to a battery
regeneration mode, which
decouples the TSI engine and
uses the electric motor as a
generator. The generating power
of the motor rises with
increased brake pedal travel.
At higher speeds, or when the
battery charge is depleted, the
TSI motor provides extra power
to recharge the battery, however
even in these situations the
charging is interspersed with
electric driving phases to
maximise fuel efficiency.
Externally, the Jetta Hybrid can
be identified by aerodynamic
modifications including a new
front spoiler, a rear diffuser
and a rear spoiler that help to
improve the car’s Cd value by 10
per cent. There are also new
headlights with LED running
lights, LED rear lights and
unique 15-inch alloy wheels with
low rolling resistance tyres.
‘Hybrid’ badges adorn the front
wings, bootlid and modified
front grille, where the
Volkswagen logo is presented on
a blue background for the first
time.
The interior of the Hybrid is
very much like that of any other
Jetta, although the electric
drive, along with a newly
designed exhaust system, an
acoustic windscreen and thicker
front side windows help to make
this the quietest vehicle
Volkswagen has ever offered in
this class.
One key interior difference is
in the instruments. If the
driver selects the ‘Hybrid’ menu
in the multifunction display,
the current drive mode is shown,
while a meter indicates energy
flow via arrows. The same
screen also shows the battery
charge state. Beneath the
energy flow diagram is what is
known as the ePower meter, which
indicates the power provided by
the electric motor.
The tachometer is replaced by
the Power meter, a multifunction
display on the left of the
instrument cluster. This
informs the driver of the
operation of the hybrid system:
‘Ready’, ‘Charge’, ‘Eco’,
‘Boost’ or ‘TSI’. The audio
system, meanwhile, has a ‘zero
emissions’ menu. This offers a
graphical display of the past 30
minutes of driving time, with a
bar showing emissions each
minute: a full, 100 per cent bar
represents no emissions at all.
Standard equipment on the
US-spec SE model includes a
2Zone climate control system
that works without the TSI
engine running, a ‘Premium 8’
sound system, Bluetooth phone
integration, MDI interface for
iPod connectivity and a
leather-wrapped multifunction
steering wheel. Moving up to
SEL1 specification adds 16-inch
alloy wheels, a glass sunroof,
RNS 315 satellite navigation,
electric driver’s seat
adjustment, heated front seats
and keyless entry. The top SEL2
specification adds to this
further, with 17-inch wheels,
fog lights, bi-xenon headlights
with cornering function, a
reversing camera and a 400-Watt
Fender sound system.
The Jetta Hybrid launches in
North America in November 2012;
there are no current plans to
sell this model in the UK.
