What is anaerobic digestion?

In a nutshell, anaerobic digestion (AD) converts organic materials, such as crops, manures and farming byproducts into biogas – a cleaner alternative energy consisting of carbon dioxide (CO2) and Renewable Natural Gas (RNG).

At Brains Farm Renewables, this anaerobic digestion process takes place in our two digesters .

We carefully process organic materials, harnessing their potential to produce biogas. This blend of biogas undergoes a meticulous refinement process in our gas upgrader to produce a purer natural gas than is currently in our pipelines.


The gas upgrader is best described as a sophisticated membrane, consisting of steel tubes densely packed with fibres. This innovative design enables the separation of molecules by size under pressure. As a result, we achieve an impressive 99% purity.


This purity is important because it means they are purer than conventional fossil fuel natural gas (which picks up contaminants from the earth where it is formed).


We then pass our exceptionally clean RNG into the gas grid’s distribution network. This means that the molecules we produce find their way into businesses and homes, to be used as fuel for vehicles and power stations, in boilers or ovens at home, and therefore contribute to a cleaner and more sustainable energy source for the community.


Who uses Renewable Natural Gas (RNG)?

In short, anyone can but whether you do will depend on where in the country your gas supply comes from. There is a network of sites like Brains Farm across the UK which contribute to the national gas grid, reducing our demand on natural gas, which is considered a fossil fuel. Every molecule of RNG we inject is one less the network has to buy in from fossil fuel suppliers that come from as far away as the USA, Qatar, Norway and Russia.

Brains Farm will produce around 50 million kWh of RNG (Renewable Natural Gas) per year.

This will then provide annual consumption for 11,213 people, or around 4,167 households.

These numbers are based on Ofgem’s calculations of the average energy use within typical homes of different sizes and with different numbers of occupants.

Frequently Asked Questions

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