Challenge -

To demonstrate the use of AMRC’s process sustainability calculator – developed as part of Project Butterfly – by analysing two composite manufacturing processes to assess the opportunity for improvements in sustainability and determining which process has a higher priority.

Background - 

The University of Sheffield Advanced Manufacturing Research Centre (AMRC) has collaborated with an industry-led consortium of partners to deliver Project Butterfly - a direct response to the urgent need to decarbonise the manufacturing industry.

The research project drives forward the innovation of digital technologies at the heart of manufacturing processes – with an aim of reducing any environmental impact and accelerating the industry’s journey to net zero. The project explores scalable digital solutions for factory processes to lower CO2 emissions by reducing material consumption and energy use.

Funded by Innovate UK under the Made Smarter innovation challenge, the project consortium comprises a wide array of partners, including the AMRC, BAE Systems, Leonardo, Nissan, Accenture, Intellium, GKN Aerospace, Moy Park and University of Lincoln, UK. The consortium represents a cross-sector interest in developing solutions for decarbonising industry and manufacturing, bringing together research, innovation, demonstration and growth.

As part of the project, the AMRC, a member of the High Value Manufacturing (HVM) Catapult network of research centres, is equipping manufacturers with innovative digital tools to assess and improve process sustainability with ease.

The two chosen processes are involved in the manufacturing of composite materials at the AMRC, often used to conduct valuable research into different composite materials and manufacturing methods. The first process involves the use of an autoclave in a preprocessing step for carbon fibre material laced with a thermoplastic powder that required curing; while the second process involves press assisted compression moulding.

Innovation - 

Both selected processes were mapped out with the start and end of the processes being defined. The resources used as part of the processes were identified and for each resource that was measured, a value for the CO2 equivalent (CO2e) was retrieved from an existing database. This allowed for the environmental impact of gathering, processing, manufacturing and using a particular resource to be equated to an amount of CO2 in kilograms, enabling it to be compared with one another using a common unit.

The routine use of the machines was observed and data was collected from a singular job for both selected processes on each machine using the AMRC’s Factory+ framework and with the help of machine operators. In addition, operators of all of the machines completed a questionnaire on the ability for both processes to be changed and/or adapted. 

Process and resource efficiency were calculated using historical data. This, combined with the changeability scores and the data collected for individual processes, was entered into the process sustainability calculator to ascertain a priority score for both processes, which were then analysed to recognise opportunity to improve process sustainability. 

Result -

It was seen in the prioritisation calculator results (see below) that overall, process one scored a higher priority and hence offers the greatest opportunity for improvements in sustainability. This higher score was mainly caused by process changeability and CO2e. Process two was used to produce a large batch of products whereas process one was used to produce a single product. 

For both processes, the raw carbon fibre material was the largest contributor to the overall CO2e. The autoclave was found to use double the amount of electricity per unit of carbon fibre and also featured significant contributions to the CO2e score, because of the bagging consumables required in the process. Both processes scored the same for process efficiency, as both were identified to have a similar tendency to fail. Additionally, both processes scored identically in terms of resource changeability. 

It was considered that some of the priority scores may have been exaggerated, as there were only two processes to compare, hence providing less context for calculating the priority scores.

Impact -

The process sustainability calculator developed by the AMRC enables manufacturing organisations to identify high-carbon intensity processes qualitatively. The tool helps manufacturers compare several processes (up to five) with the associated resources to identify areas of focus to improve process CO2 equivalent (carbon dioxide equivalent) emissions and prioritise decarbonisation efforts, based on existing sources of data.

The tool can also fill the gap between carbon accounting and life cycle analysis, and will encourage questions about how processes are set up and what can be done to make them more efficient in the short and long-run. It also accounts for the changeability factor, and taking into consideration the ease or difficulty of changing a process, leading to the identification of quick wins in industrial decarbonisation.

The tool is a comprehensive agnostic method for assessing the sustainability of manufacturing processes in any sector. The assessment enables flexibility and allows companies to choose which metrics are a priority to them.