P-23　Carbon Footprint of Products Evaluation for Bio-butadiene-derived Tires

Abstract

The carbon footprint of products (CFP) of tires derived from bio-butadiene (bio-BD) was evaluated in the life cycle assessment (LCA) method. Three locations in the Chugoku-Shikoku region where logs have been harvested in large amounts were selected. The functional unit was regarded as one tire with a driving life of 30,000 km. CO₂ emissions were calculated for each process of logging, transportation, chipping, conversion to bio-BD, tire manufacturing, transportation, use, and disposal. The CFP of regular tires was also evaluated. The CFP of bio-BD derived tires was approximately 270 kg-CO₂/tire, regardless of the location of the log harvest. These values were approximately 10% lower than those of regular tires. The processes with high CO₂ emissions were the use and raw material procurement stages. These findings suggested that making tires more fuel efficient or using biofuels are effective ways to reduce the CFP of tires.