Reliable, Renewable, Ready: The Biomethane Moment the UK Can’t Afford to Miss

For years, biomethane has quietly been the workhorse of UK decarbonisation - dispatchable, scalable, and built on familiar technology. But at this year’s Green Gas Day 2025, the mood was different. The conversation shifted from tariffs and technology to planning, carbon and alignment. The message from policymakers and industry alike was clear: biomethane is reliable, renewable and ready – now the government needs to catch up.

Policy momentum, but patience wearing thin

DESNZ confirmed that the Green Gas Support Scheme (GGSS) will run through to 2028, with an announcement expected soon on its successor. Officials were bullish - tariff levels aren’t the barrier. The real constraint is planning and permitting.

That shift in emphasis matters: if biomethane projects are to flow again, they’ll need faster approvals, clearer permitting rules or potentially even recognition as Nationally Important Projects or similar enhanced or permitted planning designation. Without this many new projects will not make a 2028 GGSS deadline when planning, construction and commissioning timelines are factored in.

Meanwhile, cross-Whitehall work is finally moving: DEFRA on digestate valorisation and feedstock waste policy, DESNZ on ETS integration, and Treasury exploring how to value negative emissions. For the first time, energy, agriculture and waste policy are pulling (roughly) in the same direction. Decarbonisation needs to offer value, and the analysis is that biomethane can offer a lot for the relative cost and deliverability.

Feedstock isn’t the problem - it’s the unlock

The Alder BioInsights study for the Green Gas Taskforce shows sustainable domestic feedstock could deliver 50 TWh of biomethane by 2030 and up to 120 TWh by 2050 - almost ten times today’s output. The feedstock is there. The bottleneck is integration.

Early RHI plants were crop-heavy; the 2018 rule change forced a pivot to residues and food waste. Now, with Simpler Recycling and End-of-Waste reforms, a new wave of feedstock is emerging: food waste doubling by 2035, livestock slurries barely tapped (only 3 % used in AD today), and rotational crops offering soil and economic co-benefits.

The transport wild card - faster decarbonisation than zero-emission trucks

For heavy goods vehicles, biomethane offers something no other fuel currently can: immediate, scalable decarbonisation using existing infrastructure.

According to the Green Gas Taskforce’s HGV study, more than 3,200 biomethane trucks are now on UK roads, cutting emissions by up to 83% compared to diesel, with potential for negative lifecycle emissions when using waste-based feedstocks.

The study found that with sustained fuel-duty support and regulatory recognition, biomethane could abate over 200 million tonnes of CO₂ by 2050 - significantly outpacing the likely contribution from zero-emission trucks in the same period.

The report calls for extension of the biomethane fuel-duty differential to 2045, recognition of its biogenic CO₂ in HGV emissions accounting, and higher RTFO targets to secure long-term investment in green freight infrastructure.

For government, biomethane also preserves fuel-duty revenue and avoids billions in grid upgrades. It’s a rare win-win that complements, rather than competes with, electric and hydrogen technologies.

For operators, it offers materially lower whole lifecycle cost compared to zero emission technologies whilst offering relatively less material requirements to operational fleet arrangements.

For investors, it reinforces that the transport market is fast becoming a second pillar of demand for biomethane - offering long-term, infrastructure-backed revenue alongside the GGSS pipeline.

From green gas to carbon removals

Perhaps the biggest storyline this year was carbon. At least 70 % of the UK’s AD fleet could capture CO₂ today, according to Ceres Group, representing over 0.5 Mt per year of biogenic CO₂. Combine that with storage access and the numbers become extraordinary: the Carbon Capture and Storage Association estimates biomethane with CCUS could deliver 17 Mt of negative emissions by 2050 - a quarter of the UK’s engineered removals - at half the cost of BECCS or DACCS.

AFRY went further, showing that biogenic CO₂ already commands a 16–24 % price premium in the UK liquid-CO₂ market, while carbon-removal credits trade at $200–$500 per tonne. But, as they cautioned, “CO₂ is putting the fizz into biomethane projects - don’t get carried away.” The opportunity is real, but depends on credible carbon standards, non-pipeline transport and GGR contracts for difference now under consultation.

Industry unity and clear asks

The Green Gas Taskforce - representing 13 of the UK’s largest AD operators, gas networks and trade bodies - has brought long-needed coherence to the debate. Their campaign, “Reliable, Renewable, Ready,” argues that biomethane is the easy win in the UK’s decarbonisation toolkit.

They’re calling for:

1. A 20 TWh national biomethane target by 2035.

2. Recognition of biomethane in the UK ETS.

3. A market for carbon removals and digestate value.

4. Extended GGSS-successor scheme beyond 2028.

5. Planning reform to unblock delivery.

What it all means for investors

For investors, the implications are both exciting and complex. Future cashflows will increasingly come from two revenue streams: gas sales and carbon value. Project models must now account for CO₂ pricing, cluster access, and transport logistics - not just tariffs and gate fees. That’s where robust financial modelling and practical advisory experience come together.

At Amberside Advisors, we’ve stood on both sides of the fence - developing AD projects and advising the investors and operators who develop, invest and operate them. We know a model is only as good as the assumptions behind it, so we work with clients to test those assumptions against real-world policy, carbon, and market dynamics. In a changing sector, the goal isn’t just to produce a number - it’s to build confidence that the decision behind it is sound.

Closing thought

As the next GGSS announcement looms, one truth stands out from Green Gas Day 2025: biomethane is no longer a niche subsidy technology - it’s a strategic asset. The feedstock exists, the carbon economics are emerging, and the technology is ready. Now it’s about joining the dots - policy, planning and investment - to turn potential into progress.

Reliable. Renewable. Ready.