We know through our work with Bio Capital that anaerobic digestion (AD) is both a circular solution for organic waste and a proven and scalable source of renewable energy.
But the development of the UK AD industry continues to face political and policy challenges. Overcoming these hurdles was a core focus for many of the presenters at the 2025 Anaerobic Digestion and Bioresources Association (ADBA) National Conference in Westminster. The event provided a meeting place for industry professionals and a forum to learn more about the current state of play in what may be a pivotal sector for Net Zero.
Greenhouse Gas Support Scheme extension
Keynote speaker Lord Whitehead kicked off the conference with a much-anticipated announcement regarding the two-year extension of the Green Gas Support Scheme (GGSS) to March 2030. The scheme has provided financial support to build and maintain the infrastructure required to inject biomethane into the gas grid since 2021, funded by a Green Gas Levy on fossil fuel gas suppliers. By extending the commissioning window, the government has ensured that investment in the infrastructure required to decarbonise the UK’s gas supply can continue for some time without disruption.
Emissions control and mitigation
Carbon capture and storage is one of the most actively debated topics in today’s climate debate. It’s also an area where AD has a demonstrable head start, as capturing carbon in an enclosed environment is an intrinsic part of the process to upgrade raw biogas into biomethane. Some AD facilities, including Bio Capital’s, have developed the capability to recover ‘food grade’ carbon dioxide for use in the drinks industry, greenhouse applications, refrigeration, and other commercial purposes. Captured CO₂ can also be stored underground or undersea through sequestration projects. According to the International Energy Agency (IEA), bioenergy with carbon capture and storage (BECCS) is the only carbon dioxide removal technique that also provides energy. Project Drawdown supports this view, rating BECCS as a highly recommended climate solution and categorising AD as a greenhouse gas reduction solution to keep watching, provided fugitive methane is effectively controlled. Whatever its source, methane is a potent greenhouse gas, accounting for 15% of greenhouse gas emissions in the UK in 2023, and its escape can easily undermine the emissions reduction potential of an AD operation.
Agricultural value add
Another beneficial AD by-product is digestate, the liquid remains of the AD process, typically stored in tanks and distributed to agricultural land. Methods of drying and pelletising digestate show promise as they make the material easier for farmers to store and handle and facilitate the switch from conventional compound fertilisers. Beyond these soil enrichment benefits, the flexible scale of AD technology itself presents opportunities for lower cost and self-sufficient farm operations. Innovations presented at the conference demonstrated how small digester units on farms can be used to manage environmental impacts such as manure runoff into waterways while providing power for small machinery and tractors.
Defossilisation
According to the latest DUKES data, AD plants generated a record 3,546 GWh of energy in 2024. A persistent controversy in the sector is whether greening the gas grid by replacing fossil gas with biogenic sources is the right solution long term. Some critics argue that maintaining a gas infrastructure prolongs our dependence on fossil fuels and cast doubts on the capacity for biomethane to make a significant enough contribution. Denmark has taken a different view, with a national gas grid that’s currently 40% biomethane, well on their way to a target 100% by 2030. Another issue is that, under current rules, biomethane must be upgraded with propane to meet specific calorific values for the grid, undermining its green credentials. The AD industry has called on the government to remove this requirement, and operators are advocating for more local grid connections to minimise the costs, risks, and emissions associated with transport and handling.
Local authority readiness
A conference breakout session with WRAP and the Local Authority Recycling Advisory Committee (LARAC) highlighted a significant gap between current local authority capabilities and the new Simpler Recycling regulations which mandate business and household food waste separation and management. These regulations are due to come into force in 2026, but a number of local authorities will be in transitional agreements, unable to meet this legal obligation due to long-term waste handling contractual obligations with non-AD suppliers. Nonetheless, the new legislation represents one of the most significant overhauls of UK waste management in decades, and the impact on organic waste volumes and processing potential will likely be considerable.
As we grow increasingly conscious of waste impacts and the urgent need for lower emission energy sources, AD offers appealing solution to turn environmental liabilities into sustainable energy assets. We look forward to watching as the industry continues its transition from a waste treatment alternative and niche energy source to a mainstream pillar of the UK’s Net Zero strategy and a model of the circular economy.
