Car weight watchers

New chassis technology should help cut emissions

As the powers that be clamp down on vehicle emissions manufacturers are looking down the barrel of massive changes in car design over the next 10 years.

By 2020 the government and EU Heads of State want a reduction in greenhouse gas emissions of at least 20 per cent, which is below 1990 levels. They have also specified that there must be a 20 per cent reduction ‘in primary energy use by improving energy efficiency’, and 20 per cent of energy consumption must come from renewable resources.

One way to combat CO2 emissions is to make vehicles lighter, which is exactly what Inrekor can do with its new chassis design. The company says it has the potential to save 10 billion litres of fuel and 50 million tonnes of CO2 emissions globally every year. Now that, as claims go, is a bold one.

Inrekor uses sandwich technology (right) to build chassis that are 30 per cent lighter than those currently used. The ultra-light sandwich structure includes a product called ARPRO® that is held between two sheets of aluminium. It is by no means an easy job using one of these chassis on an existing platform. But Stewart Morley, Inrekor’s technical director, says that this isn’t what the product is geared towards. “It’s really for small- and medium-scale production,” he explained at the product’s launch at Mercedes-Benz World. “Although it can easily be mass-manufactured, it should really help smaller, more dynamic companies with advanced vehicle technology – such as electric vehicles – to adapt quickly to a system.”

The reason the design can reduce CO2 so dramatically is due to ‘mass-decompounding’. If the chassis weight is reduced then a smaller, lighter engine can be fitted to achieve the same performance. Once you’ve done that you’ll need less structure to support it, and so the chassis weight can be reduced further. And so the cycle continues.

Sandwich technology is by no means a new phenomenon, but Morley is adamant that Inrekor is different to its forbears. “The reason why other sandwich techniques haven’t always worked is because of cost,” he says. “The secret is in the design as this dictates everything. We’ve designed the materials and parts to multitask, and we use bonding rather than traditional welding techniques so that anyone can piece together a chassis.”

The chassis is built up like a Meccano set, with each component making the structure stronger. It can be flat-packed and then assembled with the rest of the car, and the whole thing is recyclable.

Of course the burning question is whether the chassis performs like a normal one, whether the structural rigidity is the same and how it will behave during an impact. Inrekor has tested the new chassis design against an NCAP five-star-rated current chassis and was pleased with the outcome. “The results were very similar and that was with an Inrekor front end weighing 69kg and a current one weighing 105kg,” says Morley. “We can also engineer the chassis to absorb more or less impact depending on the thickness of the aluminium, on how you want it set up.” It may not be as strong as carbon fibre but, as Inrekor sales director Freddy Page-Roberts points out, carbon fibre isn’t necessarily better: “It’s expensive, they haven’t managed to mass-manufacture it and, most importantly, carbon fibre doesn’t act well in a crash as it splinters.”

So have major manufacturers snapped up Inrekor’s technology? Unsurprisingly, the company is unable to say who it is in talks with. However, I was told that it has talked to over 50 per cent of car manufacturers, and none of them are uninterested… In fact, Inrekor says it is in serious talks with more than one major car maker.

If this approach can save 30 per cent of the chassis weight while maintaining rigidity and safety at current levels, then it deserves attention. Time will tell whether this is a new direction for car manufacture.