Wednesday, 14 May 2025
A new study, led by the University of Nottingham’s Faculty of Engineering, has shown that converting food waste into biochar, a stable form of carbon, could lead to a reduction of 93,000 tonnes of CO₂ each year by 2030.
The study, published in Biochar, and conducted as part of the Department for Energy Security and Net Zero (DESNZ) Phase 2 project in collaboration with Invica Industries, explores how converting food waste into biochar—a stable form of carbon—can help reduce greenhouse gas emissions and also improve soil quality.
The report demonstrates that converting food-waste digestate, a residue from biogas production, into biochar offers a low-cost, high-impact climate solution.
The UK continues to work toward its 2050 Net Zero target, with scalable and permanent greenhouse gas removal (GGR) technologies becoming increasingly essential alongside emissions reductions.
Results from the study show that each tonne of biochar can sequester up to 1.2 tonnes of CO₂ equivalent, and co-locating production with anaerobic digestion plants, where food waste digestate is generated, could keep carbon removal costs below £100 per tonne, making it an affordable option for carbon capture. The biochar produced retains about 88% of its carbon content, effectively locking away approximately 1.15 to 1.20 tonnes of CO₂ per tonne of biochar. Applying this biochar to agricultural soils can also enhance soil fertility and structure, also contributing to sustainable farming practices.
If implemented nationally, using 50% of the UK’s projected available food-waste digestate, this approach could sequester around 93,000 tonnes of CO₂ annually by 2030. Despite challenges such as plastic contamination and fossil fuel inputs, this study highlights a promising GGR pathway that aligns with national climate targets by transforming organic waste into a stable carbon sink.
To process 50% of the UK's projected food waste digestate by 2030, 28 biochar production facilities would be required, each with a capacity of 20,000 tonnes per year.
Our research shows that food waste digestate, typically seen as a low-value, hard-to-use material, can be converted into a stable carbon sink through biochar production. This offers a cost-effective carbon removal pathway while turning a problematic waste stream into a valuable climate solution aligned with the UK’s emissions targets."
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More information is available from Disni Gamaralalage on Disni.Gamaralalage@nottingham.ac.uk
Faith Pring - Media Relations Manager
Email: faith.pring@nottingham.ac.uk
Phone: 0115 748 4411
Location: University of Nottingham, University Park
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About the University of Nottingham
Ranked 24 in Europe and 15th in the UK by the QS World University Rankings: Europe 2024, the University of Nottingham is a founding member of Russell Group of research-intensive universities. Studying at the University of Nottingham is a life-changing experience, and we pride ourselves on unlocking the potential of our students. We have a pioneering spirit, expressed in the vision of our founder Sir Jesse Boot, which has seen us lead the way in establishing campuses in China and Malaysia - part of a globally connected network of education, research and industrial engagement.
Nottingham was crowned Sports University of the Year by The Times and Sunday Times Good University Guide 2024 – the third time it has been given the honour since 2018 – and by the Daily Mail University Guide 2024.
The university is among the best universities in the UK for the strength of our research, positioned seventh for research power in the UK according to REF 2021. The birthplace of discoveries such as MRI and ibuprofen, our innovations transform lives and tackle global problems such as sustainable food supplies, ending modern slavery, developing greener transport, and reducing reliance on fossil fuels.
The university is a major employer and industry partner - locally and globally - and our graduates are the third most targeted by the UK's top employers, according to The Graduate Market in 2024 report by High Fliers Research.
We lead the Universities for Nottingham initiative, in partnership with Nottingham Trent University, a pioneering collaboration between the city’s two world-class institutions to improve levels of prosperity, opportunity, sustainability, health and wellbeing for residents in the city and region we are proud to call home.
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