Biogenic carbon: an overview                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

Biogenic carbon is carbon that is absorbed, stored and emitted by organic matter and is considered significantly different to fossil fuel that, as the name suggests, is otherwise derived from fossil fuels such as oil and gas.  

Biogenic carbon as a natural byproduct

Biogenic carbon is absorbed and stored by organic matter such as plants, crops, trees and soil, and is a natural consequence of its life cycle as, when a plant reaches the end of its life, carbon is slowly released during the process of decomposition.

Alternatively, biogenic carbon is also emitted when said plant is combusted as biomass and is therefore relevant to the Energy from Waste sector; with some experts, in fact, stating that it is essential to the future of waste management and renewable energy.

The benefits of biogenic carbon over fossil fuel carbon

Due to the nature of biogenic carbon, it is considered a clean, green and renewable alternative to fossil fuel carbon - created naturally from organic matter rather than from burning fossil fuels - where burning biogenic carbon creates green CO2 which is a more sustainable, renewable and reliable carbon emission to its traditional counterpart, as well as serving to displace fossil fuels and therefore reduce environmental impact.

What’s more, green CO2 can be used in exactly the same way as fossil fuel CO2 and is therefore considered an extremely practical, green alternative to replace traditional CO2 in industry.

Anaerobic digestion and Carbon Capture, Usage & Storage

Biogenic CO2 is released during the process of anaerobic digestion and can be captured for usage or storage - through a process called Carbon Capture Usage & Storage - and sold on to industry such as food & beverage manufacturers, making the process of anaerobic digestion essentially carbon neutral; lowering carbon emissions whilst also providing farmers and owners of the AD plants themselves with an additional income from the sale of the CO2 produced and captured.

Biogenic carbon, green CO2 and anaerobic digestion

And, whilst CCUS in anaerobic digestion is a sound concept, the issue is, however, the appetite for green CO2 generated from anaerobic digestion for use in industries such as the food and beverage.

Although the CO2 produced from anaerobic digestion is clean and doesn’t contain any contaminants from the feedstock - commonly slurry from animal waste - and is in many ways better for the environment than fossil fuel derived CO2, consumers are cautious of it; preferring not to envisage ingredients used in the production of their food to come from animal waste, making it harder to sell on.

Also important to consider is the adaptation of the AD process to incorporate CCUS and their technologies which is still in its relatively infancy; only 10 of the UK’s anaerobic digestion plants reported to be utilising CCUS in 2021.

Why is any of this important?

As a significant component of the global carbon cycle, biogenic carbon is essential for regulating atmospheric carbon dioxide levels, mitigating the impact of climate change.

More than this, however, and in anaerobic digestion, biogenic CO2 is an extremely valuable commodity; a carbon neutral alternative to fossil fuel CO2 that can be used in exactly the same way and in exactly the same industries as fossil fuel CO2; as such, capable of making a significant contribution to the renewable energy sector.