DECRYPTION – If the president was very optimistic on Sunday evening, such a transformation of the last two coal-fired power stations implies significant structural modifications. And the origin of biom raises questions.
“France will be among the first countries in Europe to phase out coal., promised Emmanuel Macron during his televised speech. With the aim of converting the last two French power plants using coal for electricity production to biom, Cordemais (Loire-Atlantique) and in Saint-Avold (Moselle).
A barely disguised attack on Germany, which, since the start of the war in Ukraine, has increased the production capacities of its coal-fired power stations. Berlin must compensate for the drastic drop in its Russian gas imports, and above all compensate for the intermittency of renewable energies (wind and solar) and the closure of its nuclear power plants. To the point of worrying the European Commission about its ability to achieve its objectives in terms of reducing greenhouse gases. The price, but also the carbon-free origin of electricity, remains a subject of conflict between the two countries.
The closure of French coal-fired power plants was initially planned for 2022, a date postponed to 2027. Like Germany, France had to review its plans due to the Russo-Ukrainian conflict. The conversion to biom of the Cordemais power plant – which belongs to EDF – has already been completed. The “Ecocombust” project was stopped in 2021, due to high costs, before being relaunched in 2022. The surge in electricity prices made it more competitive. Such a transformation involves structural modifications requiring several tens of millions of euros of work. The advantage being to maintain an existing structure rather than building new capacities. The process is proven. In Reunion, two coal-fired power plants will be converted to biom by the end of the year. They will burn bage, a residue from sugar cane.
Pressure on wood
The origin of the biom is another area of concern. Greenpeace immediately reacted to the President of the Republic’s comments to question its origin. “The UK has converted most of its coal-fired power plants to biom and now imports wood from Europe and North America», recalls Erwan Gaudemer, analyst at Roland Berger. The origin of the biom – waste from sawmills for example – must also be looked at carefully to guarantee the lowest carbon footprint. “Finally, it is also necessary to provide a factory to dry the wood», adds the expert.
The use of wood to produce electricity also risks increasing pressure on an already sensitive resource. The prices of firewood and pellets (used in stoves and boilers) are already on the rise. However, the two coal-fired power plants which will be converted to biom will have significant needs. “They risk entering into competition with other users, individuals and especially urban heating networks which, for some, already use wood boilers.», alerts Erwan Gaudemer. Especially since using wood to produce heat is approximately twice as efficient as using electricity. However, these power plants should not enter into competition with other users of biom, such as methanizers (production of biogas) or biorefineries (for biofuels) which use inputs other than wood.
0.5% of electricity production
However, at a time when the focus is on the ramp-up of nuclear electricity production and the development of renewable energies, why retain this production capacity? These power plants are required to operate in the event of high tension on the network, especially during a cold peak. Last year, coal-fired power plants accounted for 0.5% of electricity production from EDF. Preserving them makes it possible to reduce France’s dependence on electricity imports during periods when prices are particularly high and which use very polluting power plants. If their use remains the same, a few hundred hours per year, the impact will be less. But if they were to gain momentum, the problem of access to the resource could quickly come back to the forefront.