Methane emissions from biogas plants across Europe are greater than previously thought, but the majority could be eliminated at little or no cost, according to new research from Queen Mary University of London.
Published in Nature Communications Sustainability, the study measured emissions at biogas plants in the UK, Poland and Germany, finding that plants were losing an average of 14.4 kilograms of methane per hour — equivalent to around 5% of total methane produced escaping into the atmosphere unused.
Emissions varied significantly between sites. The lowest-emitting plants lost as little as 1.3 kg/hour (around 2% of output), while the highest, recorded under abnormal operating conditions, leaked up to 57 kg/hour, representing a 22% loss rate.
The researchers found that 59% of measured emissions could be eliminated at no net cost, with 83% mitigable overall using existing industry measures including gas-tight digestate storage and regular leak detection and repair (LDAR) surveys. Notably, the study found that more frequent LDAR surveys did not automatically reduce emissions — equipment quality and operator expertise were more significant factors.
The findings carry particular urgency given the EU's REPowerEU target of scaling biomethane production to 35 billion cubic metres per year by 2030, up from 4.1 bcm in 2024. The research also provides timely evidence for the European Commission as it revises greenhouse gas calculation methodologies under the Renewable Energy Directive.
Professor Paul Balcombe, co-lead on the study, said that preventing methane emissions must be a priority as the biomethane sector grows, and that cost-effective mitigation is widely available, particularly for new plants where best practice can be built in from the outset.
Biogas plant methane emissions higher than estimated, study finds
