FRIEDRICH FUEL SAVINGS

Fuel savings potential from low rolling- resistance tires Axel FriedrichUmweltbundesamt (UBA)Germany: 

Fuel savings potential from low rolling- resistance tires Axel Friedrich Umweltbundesamt (UBA) Germany

Contribution of Tire to Fuel Economy : 

Contribution of Tire to Fuel Economy Historical Trends ENERGY DERIVED FROM FUEL ROLLING LOSSES + VEHICLE LOSSES + STAND-BY LOSSES AERODYNAMICS: IMPROVING INERTIA: CAR WEIGHTS AT MAXIMUM ? TIRE ROLLING RESISTANCE RELATIVE IMPORTANCE INCREASING

Slide3: 

Test Populations (Car Tyres)   12 sets of summer tyres of size category 175/70 R13 82T 12 sets of winter tyres of size category 175/70 R13 82Q M&S 12 sets of summer tyres of size category 195/65 R15 91V  12 sets of winter tyres of size category 195/65 R15 91H M&S The measurements were carried out in 1997/1998 by the Tyre/Wheel Test Center of TÜV Automotive GmbH under contract to theUmweltbundesamt.

Slide4: 

Test Populations (HDV Tyres)   4 sets of summer tyres of size category (light truck, delivery transport)  225/70 R15C 5 sets of steered-wheel tyres of size category (medium-sized truck,) 215/75 R17,5 5 sets of drive-wheel tyres of size category (medium-sized truck,) 215/75 R17,5 4 sets of steered-wheel tyres of size category (bus, municipal transport) 275/70 R22,5 4 sets of drive-wheel tyres of size category (bus, municipal transport ) 275/70 R22,5 5 sets of steered-wheel tyres of size category (heavy truck,) 315/80 R22,5 5 sets of drive-wheel tyres of size category (heavy truck,) 315/80 R22,5   The measurements were carried out between March and June 2000 by the Tyre/Wheel Test Center of TÜV Automotive under contract to theUmweltbundesamt.

Slide5: 

Measurement Procedures         Tyre/road noise EU Directive 92/23/EEC   Rolling-resistance coefficient cR ISO 8767 (ISO 9948)   Wet braking behaviour brake distance on a wet road   size categories 17.5” and 22.5”: braking trailer with anti-lock braking system   size category 15”: commercial vehicles

Slide7: 

66 68 70 72 74 76 0,7 0,8 0,9 1 1,1 1,2 1,3 1,4 1,5 summer tyres winter tyres limit ecolabel "Blue Angel" limit ecolabel summer tyres limit ecolabel winter tyres Relation between rolling resistance and noise emission 48 car tyre types (coast-by level measured according to EU Directive 92/23/EEC, rolling resistance measured according to ISO 8767)

Slide8: 

"Blue Angel" Ecolabel for Low-noise and Fuel-saving Tyres (RAL-UZ 89) Criteria (car tyres) - coast-by level <= 72 dB(A) (92/23/EEC) - rolling-resistance coefficient: Summer tyres: <= 1.1% (ISO 8767) Winter tyres: <= 1.2% - weight: depending on tyre size: 7-9.2 kg - lifetime: >= 400 (UTQG Test, Standards Testing Laboratories, Inc. (STL), San Angelo/Texas - wet braking behaviour at least average properties regarding - aquaplaning behaviour state of the art

Influence of Compounds: 

Influence of Compounds Ultimate: Single compound tire Low RR compound ==> -52% Special low RR compound line-up

Balance of Properties: 

Balance of Properties Wet Performance Rolling Resistance Rating Silica Carbon Black Source: Goodyear

Rolling Resistance of Drive Axle Tires: 

Rolling Resistance of Drive Axle Tires

Rolling Resistance steering axle tires : 

Rolling Resistance steering axle tires

Exploring the Rolling Resistance Limits: 

Exploring the Rolling Resistance Limits Current Baseline 100 Source: Goodyear

Potential of Fuel Saving by low rolling Resistance Tires: 

Potential of Fuel Saving by low rolling Resistance Tires 30% reduction of the rolling resistance reduces the fuel consumption : city driving: 4- 6% extra urban driving ( 70 to 89 km/h ) 3- 5% autobahn driving ( 120 km/h ): 2- 3%

Conclusion: 

Conclusion The measuring results obtained show that the EU limit values for tire noise emissions are too high to bring about advances in the state of the art. Steps should be initiated to lower the limit values as soon as possible.  Since no significant conflict of aims was found to exist between tyre/road noise levels or rolling resistance and the wet braking behaviour, binding restrictions throughout the EU should be introduced simultaneously to control the rolling resistance of tyres for heavy-duty vehicles and passenger cars and wet braking behaviour as well.  In case of tires for heavy-duty vehicles, TÜV Automotive GmbH has stated that if, for example, tyres with optimised rolling resistance are used in road haulage, this will lead to a decrease in fuel consumption of between 4% and 12%, depending on route profile, speed, regularity of the speed, and vehicle aerodynamics.

www.umweltbundesamt.deaxel.friedrich@uba.de: 

www.umweltbundesamt.de axel.friedrich@uba.de