Susanna PflügerEBA's Secretary General
"Biomethane also contributes to reducing CO2 emissions from transportation, since it can be used directly in natural gas engines."
The Rise of Anaerobic Digestion in Europe
BiogasA product of the methanation (anaerobic digestion) of organic waste... production in Europe has soared over the last ten years. AnaerobicDescribes an organism or microorganism that requires an environment without air and... digestion is emerging in combination with other renewable energies as a way to achieve the European Union's energy transition targets. Here, Susanna Pflüger, Secretary General of the European Biogas Association (EBA), analyzes future prospects for the industry in collaboration with Gregory Reuland, Technical and Project Officer at the EBA.
To understand the importance of on-farm anaerobic digestion, we should first bear in mind some basic concepts.
- Biogas is a renewable natural gas made up of a mixture of compounds, predominantly methane (ch4)The main component of natural gas deposits and oil deposit gas caps. Methane is produced naturally by landfills... and carbon dioxide (CO2See Carbon Dioxid ). It is released by the natural process of bacterial fermentationThe conversion of certain organic compounds by enzymes secreted by microorganisms... , also known as anaerobic digestion, which breaks down biodegradableA substance capable of being decomposed by naturally occurring fungi and microorganisms. animal or plant matter.
- Anaerobic digestion can be used to transform organic by-products such as manure, crop residues, sewage sludge and kitchen waste into a high value-added commodity, while also capturing the greenhouse gases that some of these by-products would otherwise release into the environment.
- The process also leaves behind an organo-mineral petroleum cut (fraction) A product obtained through the fractional distillation of oil. known as digestateThe solid material remaining after methanation.. , which can be used as an effective fertilizer in farming.
- Biogas and biomethane are not the same thing: the first is the unrefined mixture of gases obtained directly through the anaerobic digestion process, and the second is purified methane once the other gases (mainly CO2) have been removed.
Biogas can give farmers a greater degree of energy independenceThe ability of a country or region to meet all its energy needs without having to import primary or final energy. , since they can use a cogenerationThe simultaneous production of both heat (thermal energy) and power... engine to produce heatIn the field of statistical thermodynamics today, heat refers to the transfer of the thermal agitation of the particles making up matter... for on-site use or electricityForm of energy resulting from the movement of charged particles (electrons) through a conductor... for use on the farm or to sell to the public grid. The biodigestate also helps them rely less on petrochemical fertilizers.
Biomethane has the considerable advantage of being an energy carrierA synonym of secondary energy (see definition). that is easy to store and transport. When fed back into the gas grid, it effectively complements other forms of renewable energyEnergy sources that are naturally replenished so quickly that they can be considered inexhaustible on a human time scale... . Biomethane also contributes to reducing CO2 emissions from transportation, since it can be used directly in natural gas engines, as well as in manufacturing, where chemical companies for example rely on natural gas for their processes.
The Development of Biogas in Europe
There were 17,662 biogas facilities in Europe in 2016, compared with 6,227 in 2009. This spectacular growth, which has leveled off since 2017, is largely attributable to governmental support programs and European renewable energy targets. France is the world's fifth largest producer of biogas, and although it still lags far behind Germany in this respect, it has been gaining ground recently.
Practices vary from country to country1; in 2015, for example, more than 52% of the matter fed into digesters in Germany corresponded to energy crops and 43% to crop residues. This was significantly different from France, where crop residues and manure represented more than 67% and energy crops only 14%.
In Europe as a whole, biogas used in cogeneration (i.e., to produce heat and electricity) still accounts for the lion's share, generating more than 250 terawatt-hours of powerIn physics, power is the amount of energy supplied by a system per unit time. In simpler terms, power can be viewed as energy output... . Use of biomethane is still in its infancy, at 17 terawatt-hours, but is growing rapidly. Led by Germany, France and Sweden, use of biomethane across Europe grew by 40% in 2016.
The increase was particularly striking in France, with use of the resource soaring from three units in 2013 to 65 in 2018, representing a capacity of one terawatt-hour/year. Hundreds more projects are awaiting connection to the grid, with some sources estimating that they represent a potential eight terawatt-hours.
The European Union has set the target of raising the proportion of renewable energies in the overall mix to 32% and renewable fuels for transportation to 14% by 2030.
No single type of renewable energy will be able to reach these targets on its own but a combination of complementary renewables could be used to achieve the energy transition.
Many projects involving European industry players, universities and research centers are currently being considered to position anaerobic digestion as a key technology in circular economy systems alongside other processes and new technologies2. Methanization may prove to play a key role in achieving the European Union's targets.
Susanna Pflüger, born in Finland in 1984, graduated in European Studies from Ruhr University in Bochum, Germany. She joined the EBA in 2012 and has represented the organization at the European Union in Brussels. She became the EBA's Secretary General in 2016.