Up to 20% of the fuel a car consumes — and up to 40% for heavy rigs — can be chalked up to the battle against the resistance of the road. Tyremakers have long tried to make tyres that are ever less resistant and save fuel and curb emissions in the process. Michelin calls its latest innovation the X Energy Savergreen, and claims it will save 500 litres of fuel per truck per year, and reduce greenhouse gas emissions by nearly 2.5 tonnes over the tyre’s ‘first life’, before it can be retread, or regrooved for further use. Michelin tyres may cost a bit more than the competition, but the company says their construction allied to regular maintenance means each one could last for one million kilometres. Goodyear has also produced a no-worse-for-the-wear tyre, the Fuel Max, which the US Environmental Protection Agency reckons will save your average 18-wheeler up to 4,000 gallons of petrol a year. Recently Goodyear joined the SmartWay Transport Partnership, a voluntary initiative of shippers, carriers and logistics firms, which aims to save a collective 6.6 billion tonnes of diesel by 2012.