Presentation of the company

Thermi-Lyon is a SME specialized in heat treatment and vacuum coating. On the Lyon site, the company has several types of furnaces (carburizing, nitriding, quenching, etc.) and related utilities (compressed air production, hydraulic cooling network, etc.).

Context and issues

In this sector of activity, energy is a major expense. This is confirmed at Thermi-Lyon where energy represents nearly 10% of turnover. Aware of this competitiveness issue, the company has committed itself to the EE-METAL program to pursue its efforts in the field of energy efficiency.

Actions

Thanks to the energy audit, the company obtained a more accurate view of its energy consumption by type of equipment. Actions have thus been implemented to optimize the most energy-intensive processes while taking into account the economic interest (ROI):

• Change of air compressor (reduction of power + variable speed motorization): saving 122 MWh/year (2% of annual energy consumption) or 10 000 €/year (3% of annual electricity bill) with a ROI of 1 year (investment of 10 k€)
• Optimisation of the furnace cooling system (rationalisation of piping on the hydraulic network + speed variation on pressure-controlled pumps): saving 175 MWh/year (3% of annual energy consumption) or 15 000 €/year (5% of annual electricity bill) with a 5-year ROI (investment of 70 k€)
• Optimisation of the office heating system (replacement of the boiler for heating administrative premises): saving 112 MWh/year (2% of annual energy consumption) or 3,000 €/year (or 4% of annual gas bill) with a 3-year ROI (investment of 10 k€)
• Reduction of the CSPE tax (reduction of the energy bill): savings of €60,000 per year (18% of the annual electricity bill) with an immediate ROI
• Renegotiation of the energy supply contract (gain on the energy purchase price): savings of 122,000 €/year (i.e. 30% of the annual energy bill) with an immediate ROI

Conclusion

All the energy saving measures identified during the audit represent a potential of nearly 20% of annual energy consumption. Other actions are therefore still being studied in order to continue improving the company's energy efficiency (increasing transformer efficiency, optimizing furnace temperatures and operating times, insulating furnaces, etc.).