A life cycle assessment study of UK decarbonised ammonia, cement, methanol and steel for emission insetting

Abstract

Many corporations are moving away from emission offsetting to reach net zero and are instead pledging to be net zero by decarbonising their own operations and activities in addition to their supply chains. When actions are taken within a supply chain to reduce greenhouse gas emissions they are referred to as emission “insets” or “insetting”. Insetting is a relatively new mechanism for company and corporate decarbonisation but there is already controversy on whether it can be effective in delivering net zero goals. For the first time, this study applies life cycle assessment and life cycle thinking to map out the supply chains of a multistorey building, fertiliser and dyed yarn production to determine what emission reductions are achievable when the supply chains of cement, steel, ammonia and methanol are decarbonised. The results indicate that greenhouse gas emission reductions can be significant with reductions of up to 17 %. Prospective life cycle assessment was applied to determine the impact of deeper decarbonisation in the supply chain, but this was found to have a limited impact with emission reductions increasing by an additional 0.12 to 8.36 %. Overall, insetting will lead to emission reductions but could cause damage to other areas of the environment including resource depletion and ecotoxicity.