Product carbon footprints on machine tools: An OPC UA based automation approach

Machining is an energy- and resource-intensive process that significantly contributes to industrial greenhouse gas emissions. To support the EU’s climate protection goals of achieving climate neutrality by 2050, it is therefore mandatory to raise transparency about greenhouse gas emissions resulting from machining processes. Due to the fact, that the resulting emissions from milling processes are based on the usage of consumables, generated waste and energy demand, the accounting of product carbon footprints is complex and often requires significant manual work. In order to minimize these efforts, this research presents a method to develop an automated system which enables CNC machine tools to automatically calculate the product carbon footprint of a milling workpiece simultaneously to the milling process. The product carbon footprints recorded are determined in accordance with ISO 14067. For emissions from electrical energy a dynamic emission factor based on the actual electricity mix is integrated into the automated system. The system is validated based on a 5-axis CNC milling process. Through improved transparency, the concept facilitates a more efficient reporting of sustainability metrics, such as the product carbon footprint. By integrating this system into manufacturing processes, companies can contribute to the EU’s climate goals through enhanced transparency and environmental accountability while reducing manual accounting efforts.