As Europe's second-largest gas transmission operator, NaTran is adapting its facilities to enable the injection of renewable gases into the French grid. Our Clemessy experts carried out a design-build project to install and commission a biomethane injection station at Fontaine-le-Dun (76), in order to connect TotalEnergies' new biomethane production site (BioNorrois) to the gas transmission network. In this way, they are contributing to the industry's energy transition towards renewable gases and decarbonization.
Nowadays, 11 million people have a gas boiler connected to the distribution network, and natural gas is also used in many industrial processes. Yet despite all the energy-saving measures we can think up, half the gas we consume today will still be consumed in 2050. In other words, consumption will fall from 417 TWh (at present) to 250 TWh by 2050, in the most energy-efficient scenario.
Natural gas (CH4 methane) is an essential component of the French energy mix, and is often equated with fossil fuels, because it is extracted from the subsoil and its combustion releases CO2. Yet when obtained from the methanization of organic matter (composed of plant and agri-food residues), biomethane is effectively a renewable gas. “The fermentation of organic matter, lasting about 30 days in a confined oxygen-free space at a temperature of around 40°C, produces biogas: CH4 + CO2. Once the CO2 has been removed, the biomethane can be injected into the transmission network. This gas is considered renewable, because the carbon footprint of biomethane produced by decomposing plants is ten times better than the footprint obtained with traditional natural gas,” explained Gas Industry Sales Manager Pierre Michelet.
The BioNorrois methanization unit
TotalEnergies Green Gases and LNG has built an anaerobic digestion plant in Fontaine-le-Dun (76), which recovers beet pulp from the Cristal Union agro-industrial cooperative by mixing 50% of it with other inputs (slurry, agricultural and agri-food waste) from neighbouring farms. Eventually, the biomethane produced by BioNorrois should cover the annual energy needs of 30,000 inhabitants (150 GWh PCS of biomethane/year).
Our experts built the containerized injection station for NaTran in the vicinity of the site, as they have done on some fifty similar sites in France. This enables the gas to be analyzed, metered, filtered and odorized to give it its characteristic smell, before injecting it into the transmission network. Earthworks and asphalt paving at the BioNoirrois methanization site and around the injection station were carried out by Eiffage Route.
As the interface between the biogas producer (TotalEnergies) and the French transmission network, our teams build biomethane injection stations, like the one at Fontaine-le-Dun, as well as backflow stations. “These control containers pilot the compressors used to reinject excess gas from the distribution zones (mainly the GRDF network) into the NaTran transmission network. They also contain gas analyzers and transactional meters developed by our teams, and require electrical, automation and instrumentation skills similar to those we developed for the injection stations,” said Pierre Michelet.
