Find out how science has helped measure CO₂ from waste to support Net Zero policy.
The UK Emissions Trading Scheme (ETS) is a major climate policy, which helps cut down on pollution. The scheme sets a limit on how much greenhouse gas different industries can release into the air and puts a price on these emissions.
As part of the UK's journey to Net Zero, the government has expanded the ETS to include waste incineration and energy-from-waste (EfW) plants. This move aimed to reduce greenhouse gas emissions further, but it brought a scientific challenge: how to accurately measure the origin of carbon dioxide (CO₂) released when waste is burned.
As part of the scheme, waste incineration companies would only pay for the fossil CO₂ they release (which comes from burning plastics and synthetic materials derived from fossil fuels) and not the biogenic CO₂ (which comes from natural materials, like garden waste).
For the policy to be fair and effective, the government needed to know if it was possible for companies to measure which type of CO₂ they were releasing. Science advice was at the heart of this project.
The Department for Energy Security and Net Zero turned to the Climate Services for a Net Zero Resilient World team, bringing together scientists, engineers and technical experts. Their aim was to find the best way to monitor and report fossil CO₂ emissions from these plants.
The team used scientific methods to explore different options that could be utilised, including:
Laboratory analysis using radiocarbon dating to distinguish fossil from biogenic CO₂
Chemical techniques to separate materials
Mathematical modelling to predict emissions
Fieldwork and practical tests to check what works best in real-world conditions.
They worked closely with plant operators, trade associations, policy makers and other experts to investigate these areas. Through interviews, workshops and questionnaires, they gathered evidence on what was practical, affordable, proportionate and accurate. Science advice guided every step, from project design to interpreting results.
Thanks to excellent science advice, the project delivered clear, evidence-based recommendations. Policy teams gained a deeper understanding of how to measure emissions fairly and reliably. The findings shaped a major government consultation, published in May 2024, which continues to guide how waste incineration is included in the ETS, beginning with a voluntary monitoring and reporting period from 2026.
