Biomethane starts with biogas: a renewable gas from the fermentation of plant or animal organic matter. That break-down can happen either naturally in the environment or artificially in digestors through an anaerobic digestion process (without oxygen): methanisation. The raw biogas comprises 60% methane and 40% CO2.
Biomethane is then obtained by purifying the biogas. This process gives it a composition similar to that of natural gas so that it can be injected into the grid. Three stages are needed to reach that point:
decarbonisation, to remove the CO2,
desulfurisation, to remove hydrogen sulfide;
dehydration, to remove water.
Once injected into gas networks, biomethane can be put to the same common uses as natural gas: heating, cooking, hot water production etc.
That gas can equally well be used as a vehicle fuel, following the same principle as NGV (Natural Gas for Vehicles), but as a 100% renewable version. This is known as BioNGV
This renewable gas has much to offer in terms of encouraging an energy transition that benefits the environment and regional economies.
This is a 100% renewable gas that can be injected into gas grids without requiring modifications to existing natural gas installations. This characteristic makes it an essential form of energy for diversifying our energy mix and rapidly lowering our fossil fuel consumption. The Long Term Energy Schedule (PPE) sets a target of 7 to 10% of gas consumption in France made up of biomethane by 2030, which is the basis of support for efforts to reduce production costs.
In addition, biomethane has a part to play in reducing greenhouse gas emissions. Its production process – methanisation – enables methane emissions released by the decomposition of certain organic materials, such as farm manure, to be put to good use.
Biomethane represents a sustainable solution and generates many positive externalities for the regions in terms of employment, and encourages the economic development of the regions. In fact, the raw materials needed for its production come from the regions: agricultural waste, or local authority and agribusiness waste. This is a locally produced form of energy. The installation of methanisation units in the regions thus allows the creation of local jobs that cannot be offshored.
Methanisation enables farmers, industry and local authorities to give their waste a second lease of life. It turns them into actors in an industry which contributes to the development of a virtuous circular economy in their region.
In addition, producing a renewable gas can help generate additional revenue. In France, to encourage the development of methanisation while protecting project leaders, a purchase tariff has been introduced for biomethane injected into gas networks. This means that producers are guaranteed a fixed price when they sell their gas under the terms of the Order which runs for 15 years. That tariff depends on the nature of the methanisation inputs and the yield volume.
biomethane connections in service on our grid in 2022
methanisation projects engaged with Teréga
GWh/year of biomethane production capacity thanks to the 14 methanisation projects engaged with Teréga