Tyres of the future
Tyres of the future: Going further with a lighter environmental load
In addition to safety features, tyre product development will, in the coming years, focus more and more on lowering the rolling resistance.
– By choosing, for example, a summer tyre with a low rolling resistance, a consumer can decrease fuel consumption by as much as half a litre per 100 km. At the same time, the car’s CO2 emissions will also decrease, says Teppo Huovila, Vice President, R&D with Nokian Tyres.
Rolling resistance refers to the energy consumed in the deformation that takes place when the tyre comes into contact with the road. This deformation, and the amount of energy it requires, can be influenced with structural and material choices in tyre design.
In electric and hybrid cars, a low rolling resistance increases the car’s operating radius when running on electricity, which is an essential feature in these car categories.
– Tyre material development actively searches for new improvent possibilities. Up and coming are, among others, the next generation silica compounds and steel belt structures. They emit less heat during the deformation of the tyre and consequently lower the tyre’s rolling resistance. In 2015, the best passenger car tyres will probably further decrease fuel consumption by 5% compared to the best of today’s tyres without compromising on the current safety features, Huovila says.
New grading system to make purchasing and comparisons easier
In addition to consumer habits, the development work of environmentally friendly tyres is boosted by the EU’s new quality grading system. By November 2012, every passenger car tyre sold in the EU must have a sticker that helps consumers decide what to purchase and to compare tyre brands; the sticker will announce the tyre's fuel efficiency, wet grip and noise level.
In principle, the new grading system will function just like the one for home appliances. The grades are A, B, C, D, E, F and G. The green A grade is the highest and best, and the red G grade the lowest and weakest.
At the moment, the rolling resistance of the best passenger car tyres corresponds to grade C of the new grading system, but the majority of today’s tyres belong to the G, F and E grades. In practice, moving from one grade to the next means that the fuel consumption of an average car decreases by approximately 2 to 3 per cent.
Results of the rolling distance test – Nokian prototype tyre rolled
nearly 130 metres, eco-oriented summer tyre about 80 metres
The rolling test of Nokian Tyres’ rolling resistance event compared an eco-oriented summer tyre that represents a good current level with the Nokian Hakkapeliitta R friction tyre and a new Nokian prototype tyre.
The test was implemented by allowing a car to roll in neutral gear off a ramp in windless indoor conditions. The distance the car rolls corresponds directly to the tyres’ rolling resistance. The farther the car rolled, the lower the rolling resistance.
The Nokian prototype tyre rolled much farther than the others, and its result was approximately 63% better than that of the summer tyre representing current technology.
- Our prototype tyre is an example of a tyre of the future, where rolling resistance is emphasised. The fuel efficiency of this tyre is nearly grade A. The product development and manufacture of such a tyre are very challenging processes. Very precise structures, smaller tolerances and the newest special materials are required. All features must be on a good level in the tyre; as a responsible manufacturer, we can never focus on improving just one feature at the expense of others, Huovila reminds us.
Results of the rolling distance test March 2010:
1. Eco-oriented summer tyre 78.9 metres
2. Nokian Hakkapeliitta R non-studded winter tyre 99.5 metres
3. Nokian prototype tyre 129 metres