Methane (Environment and Climate Change Committee Report)

Lord Ravensdale Excerpts

Tuesday 13th May 2025 Grand Committee

[Lord Ravensdale (CB)]

My Lords, first, I declare my interest as a chief engineer working for AtkinsRéalis. I thank the committee’s chair, the noble Baroness, Lady Sheehan, for all her work in steering the committee through this inquiry and for her excellent introduction to the debate. I also thank the committee and its staff, who worked really hard to produce an important report that sheds light on an important and often underappreciated facet of climate policy.

Methane is actually a really interesting technical problem due to its impact across many sectors and one that the UK has had considerable success in tackling, as other noble Lords have said. Given the comprehensive remarks from other noble Lords, I will focus on only a few areas.

To begin with, it is worth restating some of what the noble Lord, Lord Trees, said about metrics and measurements: they are central to the consideration of methane because of its nature as a flow gas rather than a stock gas. If a constant amount of methane is being emitted into the atmosphere, the warming impact will be a one-off hit. To a first approximation, the methane breaks down in the atmosphere as quickly as it is being replaced over the medium term. This is different from the nature of CO₂, which remains in the atmosphere for centuries, and therefore warming will increase over time for a constant source of emissions.

This leads us to problems with trying to apply a global warming potential to methane as a comparison to CO₂ by using a single metric, which has been the approach undertaken so far. Currently, the UK uses Global Warming Potential 100—GWP100—which is a comparison over a 100-year horizon. Analysing methane using this metric leads to a GWP of 28 for methane; in other words, it has 28 times the warming impact of CO₂. However, this figure misses the complexities in methane being a flow gas rather than a stock gas. It is worth restating what Professor Myles Allen said during our inquiry, that

“expressing methane emissions as a carbon dioxide equivalent using GWP100 overstates the warming impact of a constant source of methane by a factor of three to four and understates the impact of any new methane source by a factor of four to five”.

That illustrates that having a more nuanced view of the impact of methane emissions than GWP100 is critical for policy-making. Factors of three to five are not small discrepancies.

How the UK responds to climate change depends on a balanced assessment across emissions sources, so having a true understanding of the actual warming impact of emissions is vital. It is for that reason that the Select Committee recommended, in its recommendation 7, that the UK should unilaterally implement an auxiliary metric to better reflect the warming impact of methane and help shape effective policy in the UK. In my view, this is the key recommendation of the report, on how we view that data and how we look at those metrics. I hope that the Minister and his team can look again at the recommendation for an auxiliary metric, which would help us respond to the challenges around methane and other gases by ensuring that they are balanced effectively.

My second point is about regulation. We heard witnesses describe the complex picture around methane regulation, with overlaps between four separate regulators—the Environment Agency, the Health and Safety Executive, the North Sea Transition Authority and the Offshore Petroleum Regulator for Environment and Decommissioning—which cover agriculture, waste management and oil and gas. That is a complex regulatory picture, and in our questioning of the regulators we uncovered overlap and areas that are falling in the gaps between the regulators.

A good example of that is the Environment Agency. Witnesses from the EA stated:

“To be absolutely clear, we have no statutory duty around methane”.


It was clear from their evidence that this is a significant gap and affects how the sector is regulated. Looking more widely, this also chimes with the excellent Corry review recently commissioned by the Defra Secretary of State, which recommended that the statutory duties, principles and codes of Defra regulators should be consolidated to a core set, reflecting the Government’s priorities. If the EA and other regulators had a clear net-zero duty, this would provide important clarity and close gaps in the regulation of methane. It would also have wider benefits across the sector; for example, by streamlining the build-out of clean energy infrastructure. Can the Minister say what consideration the Government are giving to the important area of consolidating the regulators’ duties? This builds on the work that was done on Ofgem under the previous Government and through the Energy Act 2023.

The noble Earl, Lord Leicester, talked about complexity. My final point is about the importance of bringing in a systems approach to net zero to ensure that all departments and regulators are fully joined up in pursuit of this goal. Some important steps forward have been taken in this area, particularly in energy, but a 2020 report by the noble Lord, Lord Vallance, Achieving Net Zero Carbon Emissions Through a Whole Systems Approach, remains as relevant as ever. As well as recommendations on duties for regulators, as I have touched on, it includes proposals for an operational group to drive delivery across government and departments and, on the data side, for the establishment of an analytical hub. The methane issue, touching as it does many sectors and areas of the economy, is an excellent illustration of why a systems approach is required. I urge the Government to return to some of the points in the 2020 report to ensure joined-up delivery in this space and to build on the great progress being made.