Merc's new eco-friendly range

Mercedes-Benz swamped the Frankfurt Motor Show with a range of eco-friendly cars, including seven hybrid cars, eight ultra-clean diesel Bluetec models and several new engines that meet Euro 5 emissions targets due in 2009.

However, show goers were stunned by the striking F700 concept sedan, which uses an innovative DiesOtto and hybrid drive system that uses just 5.3 litres per 100km and delivers 127g/km CO2 emissions.

The DiesOtto engine, housed in a sleek luxury body called the F700 research vehicle, is claimed to provide the best elements of both diesel and petrol engines. The engine is mated to a new hybrid starter/generator and seven-speed automatic transmission. It is a four-cylinder, 1.8-litre two-stage charging petrol engine that Mercedes says combines the frugal virtues of a diesel with the low emissions of a petrol engine.

It can deliver 175kW with the electric motor producing an extra 15kW while torque is 400Nm.

Mercedes executives say the car will accelerate to 100km/h in 7.5 seconds and has a top speed of 200km/h. Apart from the engine and powertrain, the F700 has a sophisticated suspension that uses two laser scanners to view the road ahead and adjust the suspension.

The luxury Mercedes also uses a new “human machine interface” with a virtual operating assistant called the avatar which can assist the driver with specific functions, such as adjusting the airconditioning or dialling a phone number.

Visually, the F700 is based on the S-Class sedan but has an extra 285mm built into the wheelbase. The rear doors are rear hinged to allow for easy access to the roomy cabin.

The big Merc is one of the varied ways carmakers at the show are attempting to create greener machines. Car industry green expert Ted Grozier says the show illustrates how the industry is faring in its efforts to reduce its reliance on gas-guzzling larger vehicles.

“The conventional wisdom is that the US will go hybrid and in Europe the diesel is being challenged,” says Grozier, of Green Order, a New York-based advisory group that counts General Motors, among others, as clients for its advice on how to make cars cleaner. “This may be a pivotal year for the industry in the battle for greener cars and the gloves have come off.”

Indeed, BMW, Porsche, Volkswagen and DaimlerChrysler are among those showing cars with low-emission diesel engines and hybrids, featuring electricity to augment traditional fuel motors, as well as hydrogen fuel cell concepts that BMW is researching. It is all part of the effort to make high-mileage, cleaner cars that also meet drivers' expectations for performance.

Nissan showed its Mixim concept car, an electric car powered by lithium ion batteries, with the driver's seat in the middle and steering controls inspired by video-game controllers.

Unsurprisingly, it is geared toward younger drivers who spend a lot of time behind a computer keyboard. Ford showed off the current models under its ECOnetic label that produces a lower level of emissions.

France's PSA Peugeot-Citroen has its 308 BioFlex compact at the show. The car uses biofuels, or fuel obtained from crops. GM goes a step further with a car powered by a hydrogen fuel cell. The show is also a chance for carmakers to explore new concepts and designs that may or may not take shape on the assembly line. Ford is eager to pique consumer interest in its new subcompact concept car, the Verve.

If successful, it could be the basis of a new small car for global sales. It would come to Australia as the next generation Fiesta.

Designed in Europe, the Verve concept has a rounded design and is demonstrably smaller than most cars on US roads.

The president of the German Association of the Automotive Industry Matthias Wissmann says 1081 companies are at the Frankfurt Motor Show.

In total, 88 new models are debuting at the biennial event which runs until September 23.