
However, while government directives require us to act quickly and forcefully, decarbonization cannot be improvised: it is the result of a multi-part corporate strategy based on the triptych of energy efficiency, heat recovery and energy mix.
The fact that 1.000 industrial companies alone produce 80% of the CO2 in this sector suggests that it is easy to decarbonize industry and as such, the pressure on manufacturers is strong. Let us recall that in France, manufacturing and construction is the 3rd largest CO2-emitting sector, behind road transport and agriculture/forestry, with 73 million tonnes of CO2 equivalent in 2022. Faced with this pressure, manufacturers must not rush headlong into decarbonization without taking the time to establish their own roadmap.
First, before undertaking any decarbonization process, it is necessary to define the scope on which the company wishes and can act. Generally, it focuses on scopes 1 and 2, namely its direct GHG emissions linked to the plant's energy consumption. Scope 3 corresponds to other indirect emissions, those of its raw materials, their transport, its employees' home-work journeys, etc. In industry, it generally represents the scope with the highest GHG emissions in the carbon footprint of companies.
Once this scope has been defined, the first step in a decarbonization strategy is to focus on energy efficiency. Since the best energy is that which is not consumed, it is essential to rework everything that can be done in the company to improve energy efficiency. This involves initiatives and good practices, which are based on common sense: changing halogen lighting to LEDs, insulating premises, reducing their temperature, insulating pipes to avoid heat loss. In many cases, work aimed at changing working and production habits can be an interesting EE lever; for example, a bottleneck on a production line can be detrimental to energy performance. Energy audits make it possible to identify potential energy savings, determine the concrete actions to be implemented, and also assess the investments needed to optimize a site's energy consumption. Depending on the case, better energy management of factories allows for 5 to 30% energy savings.
Fatal heat recovery is an interesting energy efficiency path. In some cases, it allows the recovery of thermal discharges – cooling water, condensates, fumes, hot air, steam or process vapor, etc. – generated by an industrial process. The idea is to recover this lost heat and reuse it in the plant for another purpose, for example the production of hot water, the process itself or to supply and sell a heat requirement outside the plant.
Finally, the rethinking of the energy mix must be an opportunity to convert the energy of processes and factories, to replace carbon-based fossil fuels: gas, fuel oil and coal with less carbon-based energies: electricity, green gas, biomass, or the implementation of renewable energy (wind, solar thermal or photovoltaic, etc.), which emits much less CO2. The challenge is to establish emission reduction scenarios that make it possible to produce the same usage and improve the company's carbon performance. The adaptation of the energy mix must therefore logically take place after the energy efficiency stage. The energy mix must also take into account changes in energy costs and avoid any dependence on a single energy source.
The implementation of the various stages of the decarbonization roadmap can result in a complete overhaul of the company's philosophy in its way of doing things. This means that it must be ready to invest. To support it and help it in its decision-making, the role of a technical center, by virtue of its status, is to independently propose the staggered implementation scenarios over time that are most suited to the scope (scopes 1, 2, 3) and the pace that the industrialist has set for himself, by planning the investments estimated to be necessary in the short, medium and long term.
Tribune by François Vial, Energy Studies Officer at the Technical Center for Air and Thermal Industries (CETIAT) (LinkedIn).