The energy label for tyres indicates the rolling resistance and rolling noise level (two environmental aspects) of tyres, as well as their degree of grip on wet roads (wet traction). The label is intended to help consumers choose the most suitable tyres for their vehicle. The objective here is to enhance road safety and simultaneously reduce fuel consumption and traffic noise.
It is estimated that the potential effects of the energy label for tyres are considerable. In an external study carried out by the EU to asses the potential impacts of the label, depending on the pace of market transformation an energy saving potential was estimated that is equivalent to a reduction in the car fleet by 3 to 8 percent of all new registrations. In addition, the label is expected to reduce the level of traffic noise at source and thus increase the quality of life. At the same time, road safety has to be assured. Because a conflict arises between safety and energy efficiency, the energy label for tyres also provides information about grip on wet roads (wet traction) as an important safety aspect. The difference between the braking distance of the best (A) and worst (F) categories is 18 metres (source: Impact Assessment of the European Commission SEC 2860).
Tests have shown that tyres account for around 20 percent of fuel consumption. Here, rolling resistance accounts for 16 percent and air resistance for 4 percent. Reducing the rolling resistance results in lower fuel consumption and CO2 emissions, and thus increases energy efficiency in the road transport sector. A 10-percent reduction in rolling resistance lowers fuel consumption by around 1.5 percent, which equates to a reduction in CO2 emissions by 2 grams per driven kilometre. The reduction in fuel consumption between categories A and G is approximately 0.5 litres per 100 kilometres. Because lower rolling resistance is in conflict with a tyre’s road holding properties and thus with its safety, wet traction is also a component of the energy label for tyres.
Traffic noise is a considerable disturbance that has often underestimated consequences for our health. In Switzerland, around 1.2 million people are exposed to excessive levels of noise caused by road traffic. Noise gives rise to external costs of more than a billion Swiss francs a year (health costs, property devaluation). Because it contributes significantly to noise pollution depending on the vehicle’s speed, the rolling resistance of tyres was included in the label. A reduction in road traffic noise by 3 decibels (one label category) is equivalent to a halving of the road traffic volume, which means that, in Switzerland alone, a total of 650,000 people would be freed from exposure to excessive noise.
Appendix 4.2 of the Federal Energy Efficiency Ordinance regulates the indication of the fuel efficiency category and other properties of tyres. It stipulates how the label has to be displayed and also regulates the corresponding data that are not visible where tyres are offered for sale.
The above appendix is oriented on Regulation (EC) No. 1222/2009.
The Federal Energy Efficiency Ordinance entered into force in Switzerland on 1 August 2014. Non-labelled tyres were permitted to be introduced during an interim period up to 31 December 2014 and were allowed to be sold (commercially resold or sold to end clients) until 31 July 2017.
The label has to be displayed on or in the immediate vicinity of the tyre so that it is clearly visible and legible. It must be displayed on tyres in categories C1 and C2. No label is required for category C3 tyres.
In technical advertising material such as manuals, brochures, flyers and catalogues in printed or electronic form, as well as on websites for the purpose of marketing tyres, the fuel efficiency category, decibel level and wet traction have to be indicated. This information requirement applies to tyres in categories C1, C2 and C3 insofar as the data are available.
Advertisements on billboards, in newspapers, magazines, radio and television programmes and similar online formats (e.g. web banners) are not classified as technical advertising material. The requirement to provide information about the properties of tyres does not apply in these formats.
In accordance with Appendix 4.2 of the Federal Energy Efficiency Ordinance, It is only in cases in which a choice between various tyres is explicitly made when a new car is to be fitted with tyres that the buyer must be provided with the information about their properties. Here the information must be included in the technical advertising material.
The label comprises three classification sections:
The tyre's classification into the colour-coded energy efficiency categories A to G, based on the rolling resistance.
The tyre’s classification into wet traction categories A to G to indicate its level of grip on wet roads.
The tyre’s classification based on sound waves, supplemented by the indication of the decibel level for external rolling noise.
With the exception of the EU icons, the indication of the three classifications must be carried out as shown in the illustration. This does not apply, however, if the EU icons are already displayed in keeping with the applicable EU regulations.
Rolling resistance is measured on a test bench. Allocation to the corresponding category (A to G) is made after comparing the utilised drum test rig with a reference test bench. The method for measuring rolling resistance was defined by the relevant body of the United Nations Economic Commission for Europe (UNECE).
The wet traction level (G for grip) is determined during a test with a standardised vehicle on a wet, smooth surface based on the required distance for braking from 80 to 20 km/h. The method for measuring wet traction is defined in Regulation 117 of the United Nations Economic Commission for Europe (UNECE).
This is measured at a speed of 80 km/h, the engine is turned off and the vehicle is in neutral gear. The test stretch is specified in accordance with ISO 10844 and the measurement is standardised to a reference temperature. The limit levels for the various categories are listed in Appendix 1, EU Regulation No. 1222/2009. The method for measuring rolling noise is defined in Regulation 117 of the United Nations Economic Commission for Europe (UNECE).
The tyres are classified into categories A to G based on the measured rolling resistance coefficient. Different limit levels apply to tyres in categories C1 (for cars), C2 (for light commercial vehicles) and C3 (for heavy duty vehicles). The limit levels for the various categories are listed in Appendix 1, EU Regulation No. 1222/2009, on which Appendix 4.2 of the Federal Energy Efficiency Ordinance is based.
The tyres are classified into categories A to G based on the measured wet traction index. The same limit levels apply to tyres in categories C1 (for cars), C2 (for light commercial vehicles) and C3 (for heavy duty vehicles). The limit levels for the various categories are listed in Appendix 1, EU Regulation No. 1222/2009, on which Appendix 4.2 of the Federal Energy Efficiency Ordinance is based.
The tyres are allocated to three categories on the basis of the limit levels specified in EU Regulation 661/2009. Sound waves and the decibel level provide information about the noise intensity of the tyre. The levels pertaining to the category limits differ according to tyre width. Thus with the same classification a wide tyre can be noisier than a narrow one. The category limits are listed below:
LV: limit levels specified in Regulation (EC) 661/2009 (70 to 75 dB, depending on the nominal width, load index and winter performance of the tyre). N: external rolling noise level.
3 sound waves = N > LV: complies with the currently applicable limit levels in accordance with Regulation (EC) 2001/43 2 sound waves = LV - 3dB < N ≤ LV: complies with the more stringent limit levels specified in Regulation (EC) 661/2009, which have been introduced successively since November 2012 1 sound wave = N ≤ LV -3dB: at least 3 dB below the more stringent limit levels specified in Regulation (EC) 661/2009
With effect from November 2012, tyre manufacturers in the EU have been required to measure the wet traction, rolling resistance and noise levels of their products in accordance with the applicable regulations and to depict the results on the tyre label. Based on these data, the Touring Club of Switzerland (TCS) compiles a list of tyres on behalf of the federal government. This list can be used for comparing various products. In order to keep it as complete and up to date as possible, the list is periodically updated on the basis of data provided by the manufacturers.
The noise levels of tyres currently available on the market with identical dimensions for cars vary by up to 6 dB, which is equivalent to a reduction in the traffic volume by 75 percent. A reduction by 3 dB already equates to a halving of the traffic volume. The aim of the tyre list is to inform buyers that many tyres that have been optimised in terms of noise and safety are available on the Swiss market. Less noise means a higher quality of life.
Tests have shown that increasing the wet traction of tyres cannot be achieved independently of their rolling resistance. The label therefore provides information about a tyre’s wet traction as a safety-relevant aspect. Research is currently focused on tyre technologies and rubber compounds with the aim of finding a solution to this conflict of objectives.
The TCS tests tyres on the basis of criteria that encompass numerous safety requirements and also take account of fuel consumption. It is therefore advisable to choose tyres that have been labelled by the TCS as "strongly recommended" or "recommended".
When choosing a tyre, preference should be given to products with a positive energy efficiency rating (rolling resistance category in the green segment) if they also indicate good levels in terms of safety and noise. If a particular tyre turns out to be more expensive, the extra costs can be offset by the savings in fuel consumption.
Technical aspects relating to energy, noise and safety
The special properties of quieter tyres do not have a negative impact on safety. Experience has shown that tyres labelled by the TCS as “recommended” or “strongly recommended” are also optimised in terms of noise and comfort, and are thus quieter than those designated as “not recommended”. Tyres awarded three or four stars by TCS, and for which a low external rolling noise level is depicted on the label, are both quiet and safe. On the other hand, there is a conflict of objectives between wet traction and rolling resistance, but here too progress has been made and the first range of tyres with an A rating in both categories are already available on the market.
Quiet tyres are made with a special rubber compound using newly developed materials, and their tread is optimised for low noise. Their prices are roughly the same as those for conventional products. The mileage performance of quiet tyres is similar to that of conventional products. Although the audible rolling noise level in the interior of a vehicle is primarily attributable to the transfer of vibrations from the chassis to the car body, a certain gain in terms of comfort for the occupants can be achieved through the use of quiet tyres. By contrast, fluctuations in air pressure only have a minor influence on a tyre’s rolling noise level.
The prices of “better” tyres are more or less the same as those for conventional products, though here too there are some variations. Any additional costs can be offset through savings in fuel consumption thanks to the lower rolling resistance.
Summer and winter tyres differ not only in terms of their tread, but also in the composition of the rubber compound. The compound used in summer tyres has to be able to ensure optimal grip at high outside temperatures and is thus adapted accordingly.
Safety: at low temperatures, the rubber compound used in summer tyres hardens and becomes rigid. This means that summer tyres can no longer ensure the necessary performance. They are already unsuitable at low temperatures, i.e. not just when there is snow and ice on the roads. Braking tests at 40 km/h show that a vehicle equipped with summer tyres requires approximately twice the braking distance on snow in comparison with a vehicle equipped with winter tyres.
Safety: In the summer, all-season tyres are subject to increased wear and tear and thus deteriorate more quickly than summer tyres. In the winter, it should be noted that all-season tyres do not have anywhere near the same level of grip and traction (the force by which a vehicle is accelerated) on snow and ice as designated winter tyres. In recent years, the development of all-season tyres has focused on the requirements to be met under winter conditions (wet roads, behaviour on snow and ice). Consequently, these tyres do not function optimally in the summer. With all-season tyres, the costs associated with owning two sets of tyres (for summer and winter) can be saved, because there is no longer a need to change tyres, nor does the second set have to be stored. But since all-season tyres tend to be more expensive to buy, and their degree of wear and tear in the summer is greater, the theoretical savings are cancelled out.
Energy efficiency: all-season tyres increase fuel consumption by up to 0.4 litres per 100 kilometres compared with the use of summer and winter tyres.
No, there is no legal requirement for equipping a vehicle with winter tyres in Switzerland. However, anyone whose vehicle gets stuck on a snow-covered road with unsuitable (i.e. summer) tyres or causes an accident can be held accountable for the consequences.
Safety: With respect to safety, tests have shown that the braking distance on snow is twice as long with summer tyres as it is with winter tyres.
Safety: Winter tyres that no longer have sufficient tread (approximately 4 mm) to be used in the next winter should not be “finished off” in the summer. The rubber compound of winter tyres is specifically designed for use in colder conditions. At higher temperatures, the degree of wear and tear of winter tyres increases by up to 15 percent. As tests conducted by TCS clearly show, if winter tyres are used in the summer, their braking distance is significantly longer on wet roads and drastically longer on dry roads.
Energy efficiency: If winter tyres are used during the summer this can increase the vehicle’s fuel consumption.
Safety: TCS tests have shown that, as a tyre’s tread depth decreases, the braking distance on a wet road lengthens considerably, especially at speeds above 80 km/h. For both winter and summer tyres, the legally required minimum tread depth is 1.6 mm. TCS recommends a minimum tread depth of 4 mm for winter tyres and 3 mm for summer tyres.
Easy measurement method: insert a one Swiss franc piece into the tyre tread. If the pedestal on which Helvetia is standing is not visible, the tyre has sufficient residual tread for another summer season.
The tyre pressure specified by the manufacturer, or an indication of where this information can be found, is normally provided in the operating instructions. TCS recommends exceeding the manufacturer’s specification by up to 0.5 bar. This reduces fuel consumption, improves the vehicle’s road handling and barely reduces the degree of comfort.
Tyres are the vehicle’s sole contact with the road surface. For each wheel, the contact area is equivalent to the size of a postcard.
Safety: Low tyre pressure can make braking and steering more difficult and reduce the vehicle’s driving performance. Low tyre pressure can also be dangerous. Due to low pressure the tyre's shoulder section and side wall can be placed under greater load and its temperature consequently increases. In the worst case, this can lead to excessive strain on the tyre and cause it to burst. Electronic aids such as anti-blocking and electronic stability systems cannot compensate low tyre pressure.
Energy efficiency: Tyre pressure influences rolling resistance. In the same way as with a bicycle, if the tyre pressure is too low, more energy is required for movement. Tests have shown that fuel consumption can increase by up to 0.3 litres per 100 kilometres if the tyre pressure is too low. This means that the correct tyre pressure is not only important for safety reasons, but can also save money.
Noise: Incorrect tyre pressure can influence the way in which the tyre tread is worn down, and this can result in a significantly higher noise level.
If a vehicle is left standing where it is exposed to sunlight and the sun shines directly onto the tyres, the tyre pressure increases by around 0.2 bar. When the vehicle is in motion, the tyre pressure returns to normal. This circumstance has to be taken into account when the tyre pressure is being checked. In view of this, the tyre pressure should always before checked before departure, i.e. when the tyres are at ambient temperature.
Energy efficiency: With each additional load of 100 kilograms, the fuel consumption increases by approximately 0.5 litres per 100 kilometres. Higher tyre pressure can mitigate this effect to some extent. For lengthy motorway journeys with a heavy load, TCS recommends increasing the tyre pressure by 0.2 bar.