Biogas. When manure and agricultural waste ensured France’s energy independence

A fully loaded truck passes the scales: Tons of grain dust will be precipitated into biogas at the Equimeth methanation plant in the Paris region, reducing France’s dependence on fossil gas.

Surrounded by fields of grain, in huge tanks covered with plastic domes, there is a discreet process: turning thousands of tons of organic waste into biogas, which will supply the gas grid and help heat half a dozen surrounding municipalities.

Anaerobic digestion

Here, 25,000 tons of material, including grain dust, horse manure, and food waste… are “recovered” as the term goes. “Biogas comes from the breakdown of organic matter by a bacterial diet in the absence of oxygen,” said Arnaud Bossis, managing director of CVE Biogaz, which operates the Equimeth plant in Moret-Loing-et-Orvanne in the Seine-et-Land. Marne, east of Paris.

Arnaud Bossis explains that the biogas is then pre-treated “just to remove the methane molecule” before being injected into the gas network. To get there, the materials are first crushed and liquefied, connected to “sanitizing tanks” where they are “pasteurized for one hour at 70°C to enable sanitary treatment.” The stream is then transferred to the methanation process and stirred in a tank for 20 days, then forty days per second at 38°C.

The gas produced in this way is then sucked in the direction of the cleaning device. In this small green container, the gas is “analyzed, odorized” before being injected into the distribution network, thereby covering “15% of the population’s needs and activities”, especially heating and transport (bioGNV). Arnaud Bossis.

Odor nuisance

“In the context of the scarcity and scarcity of Russian gas, we are very happy to have biomethane in France,” says Thierry Trouvé, managing director of French gas network operator GRTGaz. According to Carbone 4, this green gas, which is “renewable” because it is non-fossil, reduces greenhouse gas emissions by 80% compared to natural gas.

However, this category accounts for only 2% of gas consumption in France. The state aims for 10% in 2030 and the sector estimates it could reach 20%, also begging for the services provided: jobs, agricultural income for farm-supported areas, fertilizer residues, etc.

Positive externalities should be taken into account for Arnaud Bossis, who mentions the relatively high production cost of biomethane, around 90 euros per megawatt hour, but now slightly less than the current prices of natural gas in Europe, which have risen significantly in the last few years. year

The main criticism against these factories: potential odor nuisance for local residents. According to Moret-Loing-et-Orvanne municipal councilor Olivier Théo, several episodes of this type reported by residents are essentially “linked to the spreading campaigns” of fertilizers produced on the site.

Full throttle independence

The creation of a monitoring committee in the spring of 2022 made it possible to quickly raise the statements of disturbed residents in one of the municipalities and to reach an agreement with the mayor to “try not to spread in the areas closest to the houses”. and ensure that fertilizer trucks do not pass through downtown, the elected official assured.

We can “achieve 60 terawatt-hours of production capacity per year by 2030, which will cover two-thirds of what we imported from Russia before the conflict,” adds Thierry Oublie.

GRTGaz goes so far as to estimate that by 2050, France could benefit from full gas independence by recycling materials and agricultural waste without affecting the potential of French agriculture for food.

“The biomethane sector in France is experiencing the fastest growth in Europe,” said the European Biogas Association (EBA), the Brussels-based biogas lobby, adding that France could become the continent’s second largest producer by 2030. .

According to the EBA, a thousand projects could see the light of day by 2025.

A provision of the Waste Management Act (Agec) should spur this development, where all individuals have a practical solution to sort their biological waste from 1.^er January 2024.