Patrick G
Mahoney
Associate
editor
Some years it ’s all
about style. Other
years it’s performance
or electronic wizardry.
But this year, escalating
energy costs
and concerns about
global warming have
designers scrambling
for the best technology
or combination
of technologies to
wring the last drop
of energy from their
futuristic concepts.
Here’s a look at some
of the contenders for
the green throne.
Jeep Renegade
The Renegade looks like a lunar golf cart. But the marketing
guys describe this two-passenger concept as a
“Bluetec diesel range-extended electric vehicle in an
open-air, sustainable design package.”
Propulsion starts with a 40-mile lithium-ion battery
pack. A range extender (small-displacement 1.5-liter,
three-cylinder Bluetec Diesel engine) boosts the range to
about 400 miles. The Diesel generates an extra 115 horses
when needed and reduces exhaust emissions compared
to standard gas engines. Renegade boasts equivalent
petroleum fuel economy of 110 mpg. Lightweight aluminum
architecture and regenerative braking improve
efficiency, and dual electric 200-kW (268-hp) motors
handle 4x4 duties.
Cadillac Provoq
Cadillac’s hydrogen-fuel-cell crossover
combines a fifth-generation fuel-cell system
and a lithium-ion battery. The fuel-cell technology
produces more power than the preceding
generation despite being only half the size. Provoq
can cover 300 miles on a single fill-up of hydrogen:
280 miles from hydrogen and 20 miles on battery electric
energy.
Two 10,000-psi (700-bar) composite storage tanks
under the rear cargo floor hold 13.2 lb of hydrogen
that feed the fuel-cell stack under the hood. Hydrogen
mixes with oxygen to
generate electricity, up
to 88 kW of continuous
power. The lithium-ion
battery pack stores up
to 9 kW-hr of electrical
energy and provides
a peak 60 kW for additional
performance.
Electricity from the
fuel cell is distributed
to a 70-kW coaxial
drive system for the
front wheels and individual,
40-kW wheelhub
motors on the rear
wheels for all-wheeldrive
capability.
Dodge ZEO
“The ZEO is designed for people
who are used to being surrounded
with information and virtual
friends at all times,” says Lou Gasevski,
principal interior designer.
ZEO stands for Zero Emissions Operation.
Dodge’s latest concept is
a four-passenger, all-electric, 2+2
sport wagon. With 23-in. wheels
on the corners, plenty of guts, and
a sassy, low profile, ZEO is a treehugging
techie’s muscle car.
The propulsion system is electric
only, with a 64 kW-hr lithiumion
battery pack and a 250-mile
range. The rear-wheel-drive’s
200-kW (268 hp) single-electric
motor chases the ZEO from 0 to
60 mph in under 6 sec, rivaling
Chrysler’s HEMI powerplant.
Lexus LF-A Roadster
One of the few concepts with no overt green
credentials was this high-performance roadster
based on the carbon-fiber and aluminum body
of the LF-A coupe. The nearly 5.0-liter V10 engine
pumps out more than 500 hp and speeds greater
than 200 mph. The engine sits in front of the passenger
compartment but behind the front-axle
centerline, a so-called “front-mid” configuration.
It’s connected via a torque tube and propeller
shaft to a transaxle controlled by paddle shifters.
The torque tube adds rigidity to the drivetrain
and chassis while it reduces vibration.
Land Rover LRX 4x4
The 2.0-liter turbodiesel hybrid can run on biodiesel. Land
Rover says this powertrain, combined with other
technologies, could lower emissions and reduce
fuel consumption by as much
as 30% compared with other
4x4s of comparable size.
Electric Rear Axle Drive (ERAD) lets the LRX use electric
drive alone at lower speeds while retaining 4x4 ability. Offroad,
ERAD provides additional torque only when needed. On
the road, ERAD lets LRX creep up to 20 mph on electric power before the engine restarts. The electric
drive continues to assist the mechanical drive until the engine runs in its most efficient range.
The engine stops automatically when the vehicle halts.
The electrical-drive system uses power stored in a high-voltage,
high-capacity, lithium-ion battery pack, independent of the normal
12-V battery. This is charged by a regenerative braking system, also
working through the ERAD.
LRX incorporates Hill Descent Control and Land Rover’s Terrain
Response, basically a sophisticated version of traction control. There
are five modes, including the “Eco” mode. Principally for on-road use,
this mode configures all the elements of the car’s system for best fuel economy. The other Terrain
Response modes are sports, general driving, sand, and ‘grass/gravel/snow’ (for slippery surfaces).
Chrysler ecoVoyager
ecoVoyager’s lithium-ion battery pack supplies primary
power for commutes of less than 40 miles.
The electric motor, which develops 200 kW
(268 hp), lets this concept jump from 0 to
60 mph in under 8 sec. Regenerative braking
captures energy and returns it to the
battery.
For occasional long trips, a small, advanced
hydrogen fuel cell extends the
range to more than 300 miles. The propulsion
system, which is below the floor, makes
more room for passengers and cargo.
Hummer HX
Even the Hummer concept boasts green credentials of a sort — it will burn E85. The HX
is a two-door, off-roader with a convertible body. Its FlexFuel 3.6-liter V6 mates to a sixspeed
automatic. The open-air experience comes courtesy of a pair of removable roof
panels above the driver and front passenger, and a removable rear-roof assembly.
The HX can be
configured as an SUT
(with the roof assembly
removed), a slantback,
or a traditional,
wagonlike design
with a bit more cargo
space. Removable
doors and removable
fender flares should
appeal to off-roaders.
HID headlamps with focusing rings adjust automatically when they’re turned on — like
the lens of an auto-focus SLR-type camera. Front turn-signal lamps and taillamps use LED
technology.
The instrument panel has an exposed, extruded aluminum cross-vehicle beam as its
foundation and sports a removable cover for storage. The concept’s four seats mount on
exposed, aircraft-style tracks.
There is no conventional radio in the HX, only speakers. Passengers plug in an iPod,
or similar device, to a USB connector. A reconfigurable gage layout uses LCD screens.
The center gage pod, which houses a speedometer and tachometer, changes to a wheelangle
indicator when the transmission is in low to give the off-roader more pertinent
information. The view of a camera mounted in the rearview mirror displays on the instrument
panel.
Like all Hummer production models, the HX has body-on-frame construction with
front and rear independent suspensions. The front suspension features an electronic disconnecting
stabilizer bar for off-roading. The heavy-duty shocks with piggyback reservoirs
are custom made, one at each wheel.
Full-time 4WD transfers torque to the front and rear axles, each of which has a locking
differential. Torque meets the trail via custom 35-in. off-road tires on bead-lock-style
wheels.
A complete armor kit protects the underbody, and there’s a power winch in the front
bumper. The four-wheel-discs are about the only thing that’ll keep this baby from humming.
Mazda Furai
Despite having a 450-hp, three-rotor rotary engine,
the Furai burns ethanol and ethanol-gas
blends. Furai means “sound
of wind.” But if this dark concept
has a sound, it’s Batman’s Theme:
The Dark Knight would feel right
at home cruising Gotham in one of
these.
This 180-mph rolling laboratory
started with a Courage C65 chassis proven in
LMP-2 endurance racing. The company has no plans to race,
build, or sell the Furai in the near future (Sorry, Bruce Wayne.)
Furai stands less than 40-in. high but it’s nearly 80-in. wide.
The Courage’s carbon-composite tub is essentially intact under
the Furai body, including the right-side driver’s seat. An electronic display screen and shift paddles are built into the steering
wheel. Doors with butterfly hinges open to the cockpit.
The wheels are 14-spoke centerlock aluminum. (Mazda has not
released vehicle specifications.)
Mazda Taiki
Mazda says Taiki’s next-generation
Rotary Engine 16X or
“Renesis,” a 1,600-cc (800 × 2) powerplant with
a new trochoid chamber shape, boosts thermal
efficiency and torque. These and other innovations
help make it a fuel miser. The shape change
increases displacement. Still, Mazda says the new
engine is as compact and lightweight as the current
Renesis.
Lengthening the trochoid radius and eccentricity
while making the rotor housing narrower brought a
longer stroke, thus shrinking the combustion-chamber
aspect ratio. And the surface area-to-volume
ratio of the combustion chamber dropped, limiting
losses from cooling. The smaller combustion chamber,
the company says, promotes flame growth for
faster combustion and better fuel economy.
This is the first gasoline rotary engine developed
to use direct-fuel injection. The system
inherits the basic design of the hydrogen rotary
engine, injecting gasoline in a high-pressure
spray during the intake cycle, promoting atomization
and vaporization of fuel and formation
of a stable air-fuel mixture. The latent heat of
fuel vaporization lowers the temperature of the
air-fuel mixture, thus raising the engine’s charging
efficiency. At the same time, it reduces fuel
adhesion to the chamber wall — a problem for
conventional port-injection systems — while
promoting a more homogenous air-fuel mixture.
This, in turn, improves thermal efficiency
and boosts torque.
Saturn Flexstreme
The Saturn Flexstreme E-Flex uses an electric
motor powered by a lithium-ion battery for
up to 34 miles of all-electric, emissions-free
range. The onboard engine extends driving
range to a total of 444 miles. GM has begun
production engineering for E-Flex, but production timing depends on continued
advancement of key technologies, specifically, the development of lithium-ion batteries
for hybrid and electric vehicles. While the featured fuel in the Flexstreme concept
is diesel, E-Flex has previously been shown in gasoline and hydrogen-fuel-cell
concepts. (Saturn has not released specifications for Flexstreme.)
Mitsubishi RA
The RA offers a twist on the sport coupe with its transversely
mounted clean-diesel engine visible through a
transparent hood. An aluminum space frame and exterior
panels made of lightweight plastic resin reduce weight.
The 2.2-liter, four-cylinder DOHC 16-valve turbo-diesel
incorporates valve-lift control with low and high-speed
cam profiles actuating the intake valves. A piezoelectric
injector, common-rail direct-fuel injection allows for a
low static-compression ratio. The turbocharger’s internal
vanes control airflow over the turbine and compressor
surfaces for optimal boost. The low-emissions diesel
delivers a maximum of 201 hp and maximum torque
of 310 lb-ft. To clean up tailpipe emissions, the catalytic
converter combines a diesel oxidation catalyst, NOx trap
catalyst, and diesel particulate filter.
Toyota A-bat
This four-passenger pickup
with Hybrid Synergy Drive
(HSD) rides on a unibody
platform. HSD is the same
drivetrain used in the Toyota
Prius. NATO’s all-terrain military
truck inspired A-BAT’s
designers to keep occupants
as far forward as possible to
maximize rear-bed capacity. A
translucent roof panel slides
open for tall cargo in the cab.
And for even more storage, a
large sliding drawer beneath
the bed is accessible without
opening the tailgate. Inside,
translucent solar panels on
top of the instrument panel
convert sunlight into energy.
BMW X6
BMW says the fuel consumption and emission ratings
of its X6 ActiveHybrid Sports Coupé are up to
20% better than comparable cars with conventional
drivetrains. ActiveHybrid has two operating
modes, one for off-the-line and
low speeds, the other for higher
speeds. A two-mode transmission
delivers variable power
via planetary gearsets. And the
transmission’s electric drive
lets the vehicle operate at fixed
transmission ratios within one system,
combining the dynamics of a
combustion engine and efficiency of
electric drive.
The X6 body is a cross between a
BMW Coup and a BMW X. The flowing
roofline, short front overhang, long
wheelbase, and long rear overhang
contribute to the coupe silhouette.
The front view and rear lights accent
the vehicle’s width, typical of an X car,
and the extra-large kidney-shaped
grille serves as air intake. Front and
rear underfloor protection panels are
brushed aluminium, and a rear panel
hides the tailpipes while driving on
electric power only.
Check this out!
To see video of the concept
cars from the NAIAS, visit:
http://tinyurl.com/2ebu6g (Toyota A-BAT)
http://tinyurl.com/2fjy55 (Mazda Furai)
http://tinyurl.com/2aaqyu (Ferrari 599 GTB Fiorano)
http://tinyurl.com/2fh6w7 (Audi R8 V12 TDI)
http://tinyurl.com/22y82x (Jeep Renegade)
http://tinyurl.com/2dppa4 (Mercedes Two-Mode Hybrid)
http://tinyurl.com/2enaak (BMW clean diesel and Dodge Viper)