Assessment of uncertainties in carbon footprint calculation at manufacturing SMEs

Abstract: The need to reduce emissions to cope with climate change and reaching the Paris agreement is an important factor for all industries. For a manufacturing company in the process to reduce emissions, it is important to know where they occur and what factors that affects emissions the most. For this the use of carbon footprint calculators is a good option, with the use of such a tool it can be easy to visualize the carbon footprint caused by manufacturing processes and use that information internally to reduce emissions. Additionally, it can also be a usable tool to provide customers with information regarding the carbon footprint of the products, which is a demand that has increased in recent years. Carbon footprint assessment will, however, always include uncertainties in emission factors since they often are tough to measure exactly or get hold of good numbers. Hence, estimations must be done in carbon footprint calculation, and estimations, depending on how they are made will always carry some degree of uncertainty. This thesis aims to identify and rate uncertainties in a carbon footprint calculation tool at a manufacturing SME. By breaking down the tool into each emission factor and assess the uncertainties by interviewing experts, the attempt is to validate the tool and establish an approach to the existing uncertainties. The goal was to validate the existing tool and suggest a method of assessing the uncertainty that is accepted by stakeholders. This was performed to make the data from CF calculation reliable. The Carbon Footprint Calculation Tool was separated into subsystems that carry out related functions to assess the uncertainty. This together with the Expert Elicitation Protocol from The IPCC allowed for layer-by-layer system validation. The analysis indicated that the Carbon Footprint calculation tool was deemed reliable enough to be utilized when the firm could update it with the findings from this thesis. Even if certain calculations may be improved by better direct measurements, the internal processes are adequately approximated from an LCA perspective. The updated estimates and information about it should make the carbon footprint calculator sufficiently reliable to be utilized, enabling Markus Komponenter and its clients to take climate action and lower emissions.