Here"s proof that Citroen’s...

Here"s proof that Citroen’s creativity is showing no signs of drying up. The C-Cactus is an eco-friendly car that, just like its prickly desert-living namesake, is very low on consumption.

Debuting at the Frankfurt Motor Show, the diesel hybrid reveals what the future holds for a low-emission, super-economical C4-sized family car. Beneath the futuristic looks – which are influenced by previous concepts such as the C-Airplay and C-Buggy – the C-Cactus houses a 70bhp 1.4-litre HDi hybrid powerplant.

Capable of running almost silently on battery power at low speed, the C-Cactus also has a 30bhp electric motor, which helps the engine at higher speeds for overtaking. As well as featuring a diesel particulate filter, the ultra-clean C-Cactus emits only 78g/km of CO2 – meaning that if it went into production, it would be exempt from UK road tax and plans for an extended congestion charge.

Thanks to the hybrid system’s ability to shut down in towns and run solely on electricity, fuel economy is even more impressive than the emissions, and on the combined cycle, the C-Cactus is said to return an amazing 97.4mpg. It is the first Citroen concept to use the 1.4-litre hybrid – previous prototypes had a 1.6-litre diesel-electric HDi. That larger motor is scheduled to arrive on models in 2010 – and it’s likely the C-Cactus’s 1.4-litre unit will go on sale at the same time, too.

Cost has always been a concern with hybrids, but Citroen claims it has found a way around this. Innovative construction techniques have allowed the firm to spend the same amount of money as it would on a conventional car during production.

All features that are non-essential to the running of the C-Cactus or the comfort of the passengers have been removed. The windows are fixed, for instance: Citroen says the automatic air-conditioning makes it unnecessary for the glass to be opened, although there are simple sliding panes for accessing ticket barriers.

Body panels have been kept to a minimum, with the front bumper section – which includes the headlamps and double-chevron badge – also making up the lower part of the tailgate. The bonnet is fixed, too: a simple flap gives access for routine maintenance.

Much of the car is made out of recyclable materials, and the cabin requires only 200 parts – about half that used for an average model. The seats are simple two-piece items, while there’s no dashboard at all. Controls for the sat-nav, gearbox and stereo have moved to the centre console.

But it’s still full of French flair, with a key that doubles as an MP3 player, a panoramic glass roof and a clip-on bag to replace the glovebox. And there’s plenty of equipment, too. A touchscreen on the centre console controls navigation and on-board computer functions. This sits between two built-in loudspeakers, minimising wiring and installation costs.

Flexibility is also good, with a sliding rear bench and boot floor that moves back to a reveal a flat load area underneath. Although the car is simply a concept for now, some of its ideas will appear on future models.

And it’s not the only Citroen at the Frankfurt expo. The firm will also show off its ethanol-powered C4 BioFlex and the C5 Airscape concept, which previews its forthcoming C5 family car.