Derived from organic materials, biogas addresses the challenges of decarbonization and energy independence while enabling regions to develop ecosystems around agricultural waste. Its many applications, from digestate as fertilizer to biomethane injected into gas networks, make biogas a key resource in the energy transition.
Biogas is produced from agricultural waste and other organic residues, which, in the absence of oxygen, ferment and transform into a gas mixture primarily composed of methane (CH4) and carbon dioxide (CO2).
This process of anaerobic digestion, called methanization, occurs naturally in wetlands but, in the energy sector, is artificially induced in a digester.
Biogas is a 100% renewable energy source.
Biogas is produced through methanization. This is a well-established process that involves breaking down animal or plant-based organic matter (from agriculture, industry, food waste, municipal waste, etc.) using bacteria in a warm, oxygen-free environment. This process generates a gas mixture containing 50-70% methane (CH4), water vapor, carbon dioxide (CO2), and other components (NH3, N2, H2S).
Biogas production is governed by strict regulations: the decomposition of waste occurs without oxygen, preventing contact with air and therefore eliminating odors. The risk of ammonia emissions into the air or water pollution from digestate is closely monitored. The integration of facilities into the surrounding landscape is considered during site selection, noise emissions from biogas units are minimal, and traffic is kept to a minimum.
Biogas can be used:
Today, biomethane production is driving the rapid growth of the biogas sector.
What are the objectives for biogas?ENGIE has ambitious goals for methanization, both at the European and national levels, driven by the availability of resources and the crucial role renewable gases play in decarbonizing the energy mix. Biogas production is primarily intended to be transformed into biomethane to decarbonize natural gas supplies. |
ENGIE is among the leaders in biogas production in France, through its subsidiary ENGIE BIOZ, which develops, finances, and operates anaerobic digestion units.
Currently, ENGIE operates 36 production sites in France, 22 of which are majority-owned and 14 minority-owned.
While most of ENGIE’s methanization units are focused on producing biomethane for injection into the natural gas grid, a few units use biogas directly, particularly for cogeneration. Of the 22 majority-owned plants, 20 inject biomethane into the natural gas grid, while 2 operate through cogeneration (Neubourg Biogas Plant and Montauban de Bretagne Biogas Plant).
ENGIE produces over 700 gigawatt-hours (GWh) of biomethane annually in France.
Source : ENGIE, Renewable Gas Europe, 2024
➡️ The Case of Montauban-de-Bretagne Biogas Combined Cycle Power Plant
Designed and operated by ENGIE BIOZ, the cogeneration plant was commissioned in 2017. It generates 9.4 GWh of green electricity, equivalent to the annual consumption of about 2,000 households, as well as thermal energy for heating nearby greenhouses (> 6 GWh).
The digester can process up to 98 tons of input per day, 60-65% of which comes from agricultural sources (effluents), 30-35% from agri-food industries, and 5% from municipalities.
This project brings real value to the agricultural ecosystem, with 43 farms using digestate over a total spreading area of 2,752 hectares. This results in 190 tons of nitrogen being redistributed locally, partially replacing imported mineral fertilizers.
Environmentally, the plant avoids 5,000 tons of CO2 emissions per year.
The Montauban de Bretagne plant showcases how anaerobic digestion can integrate into local communities, bringing together economic actors, farmers, the agri-food industry, the municipality, the Saint-Méen-Montauban community, greenhouse operators, and electricity grid operator Enedis.
ENGIE is strengthening its presence in Europe through acquisitions in the UK (4 production units) and the Netherlands (2 units).
In total, our installed annual production capacity stands at 1.1 TWh of biomethane as of June 30, 2024.
