How does anaerobic digestion generate biogas?
At Good Energy, we use biogas both in our 100% renewable electricity supply, and as part of our green gas product.
But what is biogas and how is it generated? Read on to find out.
What is biogas?
Biogas is different from ‘natural gas’ which is extracted from rock via drilling or fracking.Instead, biogas is generated from organic matter and contains around 60% methane and 40% carbon dioxide.
It is made from a process called anaerobic digestion (AD), where microorganisms break down plant and animal products in a sealed, oxygen-free tank.
Refining the biogas and removing the carbon dioxide creates biomethane, which can be pumped into the public gas grid and used in the same way as natural gas. 10% of Good Energy’s green gas product comes from biomethane.
Biogas can also be burnt to generate renewable electricity. See our current fuel mix to see how much of our electricity comes from biogeneration.
How does anaerobic digestion work?
Organic waste including plants, food waste and manure is fed into a sealed tank, where it can be broken down by bacteria in an environment with no oxygen. The bacteria produce methane amongst other gases, which gets pumped off as biogas.
Solid or liquid material left over from the process is called digestate. This can be used by farms as crop fertiliser, livestock bedding or as enrichment for soil due to the high nutrient content. In this way, anaerobic digestion becomes part of a circular renewable system.
Good Energy’s position on sourcing biogas
We aim to source biogas in as sustainable a way as possible, by buying from generators with high environmental standards. We follow key principles, which you can read about further in our biofuel procurement policy. These include:
- The biofuel must be either renewable or from waste, with transportation kept to a minimum.
- Ue of energy crops must be kept to a minumum, and only from managed, sustainable sources
- Where animal waste is used, high welfare standards must be met.
Is biogas an important part of the UK fuel mix?
Biogeneration is a hugely important part of the UK fuel mix, and is a key part of the UK’s strategy to have a 95% low carbon electricity grid by 2030. This is because, unlike wind and solar electricity which vary with the weather, biogeneration can provide a consistent low carbon power baseline.
We match an industry-leading 88% of our customers’ electricity use with renewable electricity generated within the same half hour. This is independently verified by the Matched Clean Power Index, where we are ranked #1 in the UK for time-based matching. This matters because electricity can’t be stored at scale – it needs to be used as it’s produced. To get Britain’s grid to 100% low carbon, we need renewable generation that reflects how people actually use power. That means generators spread across the country and across technologies – including variable wind and solar, and more consistent biogeneration and hydro.
Electricity reaches you through the National Grid, which contains electricity generated from a mix of sources, including fossil fuels. We match all of the electricity you use with 100% renewable electricity sourced from our community of over 3,300 independent renewable generators.
Good Energy ranked #1 in the Matched Clean Power Index, an independent assessment of how closely UK suppliers match renewable generation to customer demand on a half hourly basis. Comparison verified at https://matched.energy.
