Radical green 4WD designs

Most of the news from last week's North American International Auto Show in Detroit was about alternative fuels, green power and the poor state of the US economy.

But if you looked hard enough, there were some cool cars to be found — as well as the wild concepts for which the Detroit show is famous.

Even though makers spoke of being kind to the environment, 4WDs and SUVs were prolific, including innovative concepts by the big three: Jeep, Land Rover and Hummer.

Jeep Renegade

Even the 4WD concepts were green-tinged. Jeep's Renegade buggy features a hybrid power train with a 1.5-litre, three-cylinder, turbo diesel engine and a pair of 200kW electric motors, one at each end.

Touring range on electric power only is a claimed 64km from the 16kWh Li-ion battery, with a total range of 640km when used with fuel.

It wasn't just the Jeep's power train that was designed to give show-goers a warm and fuzzy, saving-the-world kind of feeling. Much of its structure was created from recycled or recyclable materials.

The Renegade's Palm Green metallic colour is moulded into its plastic body so as not to require paint (and the pollutants associated with paint).

The seats were made using soy-bean foam and, where possible, parts were made from a single piece to avoid the use of toxic resins.

The Renegade can be configured with a range of tops and rear sections to accommodate the various cargo requirements of an outdoor sportsperson. At the show, it was topless — and in the rear was a pair of water scooters ready for a scuba trip.

If your idea of sport is limited to off-road driving, the Renegade won't disappoint. Its full-time 4WD system includes front and rear differential locks and low-range gearing.

A combination of steep approach and departure angles, good ground clearance and low weight enhance the Renegade's off-road ability.

Hummer HX

This was undoubtedly one of the stars of the Detroit show. The two-door, four-seater is smaller than the Hummer H3 and, although not built on an existing platform, could be a clue to the much-rumoured H4 said to be in development.

Power comes from a direct-injection petrol V6 engine that gains its green credentials by being ethanol-compatible.

Ethanol is GM's immediate answer to reducing vehicle emissions, and the company is investing heavily in technology to better produce the fuel.

Like the Renegade, the HX is a versatile machine with removable tops

and slant, square or no back sections. Its doors and wheel-arch flares are easily removable.

Steep approach, departure and ramp-over angles, 35-inch tyres, long-travel, coil-over suspension, front and rear diff locks and a front-mounted winch are there for serious off-roading.

Unlike the minimalist Jeep, the HX is loaded with tricks and gimmicks. In its many nooks and crannies were iPod/iPhone holders, a shovel, a fire extinguisher, satnav and LCD displays.

A forward-facing camera in the rear-view mirror allows you to record your off-road driving adventures, which can be downloaded to the iPod.

Lightweight folding seats, inspired by aircraft seating, have storage space underneath them.

The HX was designed by a team of youthful designers whose input will appeal to younger Hummer buyers who want a no-compromise vehicle.

If GM can create a production version of the HX that is anywhere near as wild and versatile as the concept, it's sure to be a hit and could heavily infringe on Jeep Wrangler sales.

Land Rover LRX

Whereas the two American concepts are wild off-roaders, the LRX is a prestige compact SUV better suited tothe urban jungle.

It's Gerry McGovern's first offering since he became Land Rover's chief of design, and is predicted to point closely to a fifth nameplate from the British marque, which celebrates its 60th year in 2008.

If you think back to the Range Stormer concept and its relationship to the Range Rover Sport, hopes are high that we'll see something like the LRX in the near future.

The LRX is a two-door SUV smaller than the Freelander 2, the smallest vehicle in Land Rover's current model line-up.

Power comes from a two-litre turbo diesel/electric hybrid drive train with an electric motor integrated into the rear axle in what Land Rover calls Electric Rear Axle Drive (ERAD).

Like most hybrids, the LRX runs on its electric motor only at low speeds, switching to a combination of electric and internal-combustion power under hard acceleration, then to diesel only for cruising.

ERAD can supply additional torque to all wheels during off-road use or when more traction is called for.

Like the Freelander 2, the LRX is more road-oriented than other vehicles in the Land Rover range.

Its version of the acclaimed Terrain Response adds two new settings — “Sports” and “Eco” — to the dial.

As their tags suggest, these settings optimise the mechanical systems in the vehicle for either enthusiastic or economical driving.

The other Terrain Response modes are “Normal” for everyday use; “Grass, Gravel, Snow” for low-grip surfaces; and “Sand” for beach work.

Any production version of the LRX would be pitched at upwardly mobile young executives who are looking for a premium sports SUV but don't want, or need, the ability and size of the Range Rover Sport.