Citroen C-Cactus concept’s green secrets

Published: 17 September 2007

Citroen C-Cactus: the lowdown

Citroen’s C-Cactus concept car on show at Frankfurt signals the start of a programme to investigate simplifying the construction of its cars –stripping out unnecessary weight, complexity and emissions from its everyday hatchbacks and saloons. And it’s not as far flung as it looks. Its designers told CAR Online that this concept wasn’t about the external design, but rather the way the project was conceived and built. This is ‘an ideas car’. So forget the cutesy look of the C-Cactus and concentrate instead on the fact that it weighs an impressive 400kg less than a conventionally fuelled C4 upon whose underpinnings it rides.

Lightweight Citroens, you say? Sounds good…

‘We didn’t want to work just on the technology in the car’ said Gilles Vidal, the designer. ‘We wanted to look at the whole environmental question from dust to dust. We quickly realised we wanted a lighter car. There’s a virtuous circle where you add some new technology, and before you know it you need bigger brakes to stop the heavier car, and weight just balloons. The C-Cactus is an attempt to get away from that.’ So how have they removed weight? By going back to the drawing board and reassessing everyday needs, especially in the interior. Do we really need bulky window winding mechanisms? Not really, they found, so the C-Cactus has just a small sliding flap for handing over toll money. This means the door panel is now a one-piece pressing that’s cheaper to make and lighter. And its decorative element uses simple cut-outs revealing a contrasting material behind. A simple way to include eye-pleasing cabin design without the need for extra chrome strips or wood fascias. And rather than hiding a lot of the car’s innards behind plastic cladding, the designers have instead tried to make features of them. So the air-con system is on view where a centre console would normally sit. That’s right, the C-Cactus doesn’t even have a dashboard.

So how lightweight is the C-Cactus?

Citroen says it decided to use the weight saving to counter the effect of installing a hybrid powertrain. So it uses the same diesel-electric system as the 308 and C4 hybrid prototypes; these will hit the market by the end of the decade. ‘Our system adds around 120kg,’ said Vidal. ‘But thanks to our weight savings elsewhere, the car isn’t too heavy as is the norm with hybrids.’ This concept car weighs in at 1180kg – not exactly a flyweight, but impressive for a hybrid, especially a diesel one. The C-Cactus has some good ideas, but it will be interesting to see if Citroen can incorporate some of this thinking into production cars soon. The front grille and light surround is identical front and rear (making it cheaper and simpler to manufacture) and even the doors are polished metal, with no paint. ‘It’s all about looking at the bigger picture,’ said Vidal with a smile.

By Tim Pollard

Group digital editorial director, motoring news magnet