Carbon Footprint of Wool at Cradle to Farm-Gate Stage in Victoria, Australia

Abstract

The raw material acquisition stage of wool involves raising sheep and a large amount of input and output, resulting in substantial greenhouse gas emissions. To date, the research literature on wool carbon footprint is limited, and there is a lack of research on Victoria. These studies did not consider the influence of changes in weight and productive lifespan. This study aims to address this knowledge gap by calculating the wool carbon footprint in Victoria and improving the calculation method. In this article, 20,000 sheep in Victoria were investigated. The average weights of the sheep were obtained by curve fitting and calculating. Two scenarios with 5-year and 6-year productive lifespans were used to calculate the carbon footprint of merino wool by the mass allocation method, economic allocation method, and protein mass allocation method. Results revealed that the carbon footprint of wool for the 5-year and 6-year productive lifespans were 14.158–49.040 kg carbon dioxide equivalent (CO2-e)/kg wool and 16.743–52.882 kg CO2-e/kg wool. Rumination and excretion accounted for the largest proportion, followed by phosphate fertilizer, electricity, and potash fertilizer. The longer the productive lifespan and the heavier the sheep, the greater the greenhouse gas emissions from rumination and excretion, leading to a larger carbon footprint for wool. For the same productive lifespan, the economic allocation method produced the highest carbon footprint for wool compared to the mass allocation method, which produced the lowest carbon footprint. This study provides a reference for the subsequent carbon footprint accounting of wool from cradle to farm-gate and helps the wool industry save energy and reduce emissions.