According to a current study by the Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT), retreaded tyres produce over 60 percent less CO2 emissions than new tyres of comparable quality.
Life Cycle Analysis Shows Environmental Benefits of Retreaded Tyres
The study commissioned by Allianz Zukunft Reifen (AZuR), which is part of a project funded by the Deutsche Bundesstiftung Umwelt (DBU) with around 91,000 euros, has come to the conclusion that the main reason for this is the saving of energy (electricity/gas) in the manufacturing process and the reduced use of raw materials.
The findings of the study were presented to stakeholders and the media on September 20 at the Baden-Württemberg State Representation in Berlin.
In the carbon footprint analysis produced by UMSICHT retreaded tyres came out clearly ahead of qualitatively comparable, high-quality new tyres. During the manufacturing process, a retreaded car tyre causes around 21 kg or 63.6 percent less CO 2 emissions than a new car tyre. A retreaded truck tyre causes around 135 kg or 63.6 percent less CO 2 emissions than a new truck tyre. In 2021, around 114,240 tons of CO 2 emissions were saved in Germany through the production of retreaded tyres (in relation to qualitatively comparable, high-quality new tyres).
In the Fraunhofer study, both the production phase and the use phase, which is largely determined by the rolling resistance of the tyre, were taken into account. The measurements of the rolling resistance by the testing laboratory North showed that retreaded tyres for the selected tires/dimensions achieve the same rolling resistance class (car: C, truck: D) as the new tyres on whose carcass they are based.
The total CO 2 emissions from retreaded passenger car tyres with a mileage of 20,000 km and 40,000 km are below those of qualitatively comparable, high-quality new tyres. With a mileage of 20,000 km, retreaded car tyres save almost 100 kg of CO2 Equivalent/100,000 km compared to comparable quality new tyres. In summary, the study confirms that retreaded passenger car tyres save CO 2 in all scenarios. According to the scientists, the advantages of the CO 2 savings gained during the production process clearly outweigh the rolling resistance, which is only 1 percent higher compared to new tyres of comparable quality.
With a mileage of 150,000 km, the total CO 2 emissions of retreaded truck tyres are roughly the same as high-quality new tyres of comparable quality. With a mileage of 65,000 km, the CO 2 footprint of retreaded truck tyres is smaller than that of high-quality new tyres of comparable quality.
The lead of retreaded tyres in the life cycle assessment increases by considering the energy (electricity/gas) and raw materials used in the manufacturing process. In 2021, retreading (without material production) in Germany saved more than 14.1 million kWh of electricity and around 46.9 million kWh of gas in relation to qualitatively comparable, high-quality new tyres. The energy requirements for this study were determined by AZuR.
Around two-thirds fewer raw materials are required to manufacture retreaded tyres than for high-quality new tyres of comparable quality, which conserves natural resources. Around 5.88 kg fewer raw materials (primarily rubber compounds for treads and sidewalls) are required to produce a retreaded car tyre. Retreading a truck tyre saves an average of more than 44 kg of raw materials. In 2021, around 37,000 tons of raw materials were able to be saved nationwide by retreading.