The approach initiated by Verallia consists of analyzing the energy consumption of the main non-melting equipment: air compressors, fans and annealing arches. This analysis makes it possible to compare current consumption with theoretical consumption calculated using digital models. The difference is then analysed in detail to identify the origin of the losses; for each identified loss, technical solutions for improvement are proposed and an efficiency calculation is made for each proposed action. A methodology is applied to enable a systematic and detailed analysis of all aspects of consumption. The maximum value of unidentified losses is set at 5% of the theoretical consumption value. An efficiency calculation incorporating the cost of CO₂ is used to prioritise investments.
This approach then makes it possible to optimise energy consumption, electricity and natural gas, on compressors, fans and annealing arches. The reduction in emissions remains modest for each project but the number of projects is significant:

• Dozens of projects concerning annealing arches
• More than 100 projects concerning compressed air production

For example:

• The reduction of heat loss from the arches and the improvement of their operating conditions has 150 tCO₂/year by limiting gas consumption.
• Optimisation of electricity consumption for the production of compressed air and ventilated air, but also, more simply, of the consumption of electricity.