The Greenest Tyres

Tyre manufacturers have been using recycled rubber in agricultural and OTR tyres for some time, but new research shows that lower rolling resistance passenger and truck tyres could be greener still if they also used ultra fine recycled rubber powder in their compound recipes.

At the end of May, Rice University’s Marc J Epstein and business academic Tamara Bekefi published a fascinating paper entitled: “The Value of Green Tyres to Corporate Pofitability.” The paper looks at the current environmental and economic situation and points out that there is a “real possibility that the supply of virgin rubber will not be able to meet demand in the coming years.” It may not get to this point immediately – research conducted by Deutsche Bank analysts shows that, having gained a huge 40 per cent this year, natural rubber prices are now beginning to level off to their 18 month average and may follow fuel price falls – however, looking to the longer term, Epstein and Bekefi’s point still stands. The US Energy Information Administration estimates that the road vehicle population will grow from 170 million vehicles in 1996 to 454 million in 2020 in developing regions. This increased demand for cars translates into a massive increase in demand for tyres and if prices are high now, how much higher will they be in the face of this demand in 12 years time. Will supply even meet demand?

Epstein and Bekefi’s suggested solution is the increased use of ultra-fine recycled rubber powder, which has the duel effect of saving both natural rubber and oil-based synthetic rubber. By using ultra-fine recycled rubber powder as a substitute for 10 per cent of the rubber need in producing a new tyre, manufacturers are expected to save the equivalent of a gallon of oil for per tyre produced. This equates to more than half a billion gallons of oil annually. With this in mind, and adding in the fact that retreads use a third less oil in the first place by reusing worn casings, could using re-used rubber in the production of retreading compounds make the greenest tyres of all? (See this month’s 32-page Retreading Special supplement for more on what green tyres mean for the retread manufacturing industry)

Using ultra-fine recycled rubber powder in new tyre production is also said to have positive effects on low rolling resistance compounds – a subject that many new tyre manufacturers are keen on getting on being linked with. According to a Georgia Institute of Technology study, engineered recycled rubber reduces a key rolling resistance related characteristic by 15 per cent and improves air retention by 19 per cent, therefore both directly and indirectly reducing fuel consumption.

So why not use recycled rubber in passenger and truck tyres? The key reason the main new tyre manufacturers don’t do this yet (or at least don’t shout about it) is because of image. However, as consumer awareness of green issues increases, and as fuel prices remain high, some observers are predicting a warmer reception for this kind of green tyres than the new tyre manufacturers may have previously feared. According to Epstein and Bekefi, given the choice between eco and non-eco products, “consumers buy “green” when the products on offer are of equal price and quality.”