Usually in a float glass furnace, the glass is melted thanks to the heat produced by the combustion of fossil fuels. Natural gas burners radiate above the glass melt, allowing it to reach the 1.600°C melting temperature. Electro-boosting is based on the fact molten glass is an electrical conductor. Thanks to the injection of electrodes in the glass bath, the current passes from one electrode to another. By doing so, the current generates heat inside the glass in a way that is twice as efficient as with fossil fuels. The overall energy efficiency is then doubled. Since the electricity used has a low emission factor (**), the CO2 emissions’ drop is significant. Best case scenario, the emitted CO2 per molten ton is 6 times lower, when we switch from natural gas to a low carbon electricity.
(**) The emission factor is the amount of CO2 that 1 MWh of energy will emit during its production or its usage, whatever its type (fossil fuel or electricity).
In 2022, the first furnace was equipped with the electro-boosting technology in Moustier, during the cold repair of the furnace. The technology was also installed on the float line in Seingbouse*** (France). This time when the hot furnace was in operation, which is a very challenging intervention. In the upcoming years, all our other float lines in Europe will be retrofitted with electrical melting.
(***) The installation in Seignbouse was partly funded with a grant as part of the French economic stimulus program “France Relance”, financed by the European Union – NextGenerationEU . The program “France Relance”, operated by ADEME, helps to enable the decarbonization of the French industry.
More on our decarbonisation journey
Sustainable sourcing of raw materials will not only limit our impact on climate, but will also allow limit our use of natural resources, minerals and water, whilst insuring that the supply chain is fully compliant with regulations such as REACH or Conflict Minerals.
Hybrid melting is a combination of the oxy-combustion technology and electrical melting technology.
It is a technical breakthrough compared to the current technology used in flat glass furnaces fired by natural gas.
Use of green energy
Using green energy resources is essential to achieve carbon neutrality. AGC is working on maximising on-site energy recovery and on- and off-site renewable electricity generation.