On-Demand Knitting and Recycling: An LCA Study Investigating an Integrated Solution for Sustainable Woollen Jumpers

The purpose of this research is to reduce the environmental burden of textiles, specifically focusing on the production of Merino woollen jumpers. The study addresses two techniques to lessen the environmental burden: (1) recycling of wool garments by shredding or unravelling and (2) preventing the overstocking of products through on-demand knitting. The environmental burden is measured via LCA using Idemat. The results are reported in terms of eco-costs (EUR) and carbon footprint (kg CO₂-e). A cradle-to-gate analysis of recycling by either shredding or unravelling is compared with the use of virgin wool. The results are: EUR 3.53 in eco-costs and 21.93 kg CO₂-e as the carbon footprint for a virgin wool jumper to EUR 0.31 eco-costs and 1.56 kg CO₂-e for a recycled wool jumper and EUR 0.19 eco-costs and 0.89 kg CO₂-e for an unravelled wool jumper. Additionally, a cradle-to-grave calculation per wear was made, resulting in: EUR 0.045 and 0.278 kg CO₂-e, EUR 0.004 and 0.020 kg CO₂-e, and EUR 0.002 and 0.011 kg CO₂-e, respectively. A revenue-normalized comparison between on-demand knitting and mass production based on the eco-costs/value ratio (EVR) shows a 44% higher environmental impact for a mass production system.