In this article, a new method to measure energy efficiency in manufacturing processes, with a focus on electric energy use, is described. The goal is to create a system to compare energy efficiency across different products. The key figure used is called Relative Energy Efficiency (REE), calculated by dividing the minimum energy needed by the actual energy consumed. They introduced the Least Energy Demand Method to identify the minimum energy required for specific production tasks. This method can help companies pinpoint where they can save energy and improve efficiency in their manufacturing processes.