The Ledger Nobody Watches

On 28 August DESNZ filed a document nobody covers, because nobody is meant to. I read it, so you don’t have to — and the number inside is worth fifteen years of your gas bill.

ON 28 AUGUST​ the Department for Energy Security and Net Zero published a document. It’s called an Expenditure Forecast Statement, it runs to a handful of pages, and it exists because Regulation 20 of the Green Gas Support Scheme Regulations requires it every quarter. Nobody seems to have noticed, and that seems to be the intention. It sits on gov.uk under a heading built for regulators to tick a box rather than for the public to notice. The most reliable way to keep a number out of the public conversation is to publish it correctly, on schedule, in a format nobody thinks to read.

The number is £190.82 million. That’s DESNZ’s own maximum committed spend on the Green Gas Support Scheme (GGSS) for the twelve months from 1 August 2026. Three months earlier the equivalent figure was £139.03 million. Twelve months earlier, £98.42 million. That’s a 37% rise in a single quarter and a 94% rise in twelve months, and it rests on 33 applications that have cleared Stage 2 of the scheme’s approval process. The levy that funds the scheme is calibrated to a lower “projected expenditure” figure of £134.2 million rather than to this £190.82 million ceiling. The forecast is a maximum liability, not a spending total. But the ceiling is still the number worth focussing on, because each of those 33 Stage–2 passes is a tariff guarantee, and £190.82 million is what future levy-payers are on the hook for if every one of them converts to full accreditation.

None of it comes out of general taxation. It comes out of the Green Gas Levy, sized this year to the £134.2 million the scheme is expected to spend rather than to the £190.82 million ceiling above it — a flat charge of £3.82 a year, or just over a penny a day, on every gas meter in Great Britain, domestic and business alike. Nor does it appear as a line item on your bill. It’s folded into the standing charge, the way the Renewables Obligation and the Contracts for Difference levy are already folded into your electricity bill. The department publishes the number each quarter. It does not publish what any of it means for the person paying it, or how it adds to every other levy already sitting on the same bill.

Each of those 33 approvals is a 15-year tariff commitment rather than a one-off payment. The £190.82 million is a floor, committed to this quarter, under a levy line that runs to 2041 regardless of gas prices, biomethane economics, or anyone’s attention span between now and then. The scheme remains open to new applicants until at least 31 March 2028, with a further extension to 2030 announced though not yet confirmed as law, so this isn’t a closed history you can total up and file away. It is a live trajectory that gets longer every quarter nobody reports it.

To be fair, there is a case for the scheme. ADBA, the trade body for anaerobic digestion, argues that biomethane is unlike wind or solar in a way that matters: it’s dispatchable, it behaves like ordinary gas once it’s in the grid, and it displaces imported gas rather than adding intermittent capacity that needs firming up behind it. ADBA’s chair, Chris Huhne, put it this way on the announcement of the scheme’s proposed extension: “Today’s announcement demonstrates that the Government recognises the critical role biomethane plays in delivering net zero and bolstering the UK’s energy security. By extending the Green Gas Support Scheme, ministers are ensuring that investment can continue to flow and that new plants can continue to come online, delivering clean, reliable, home-grown gas.” None of the usual intermittency critique applies here. That’s a genuine point in the scheme’s favour.

Against it sits Regen, a decarbonisation consultancy commissioned by the MCS Foundation, which has looked at how far biomethane could realistically go. Its verdict: under 18% of the UK’s current gas demand even in the most optimistic supply scenario, against ADBA’s own claim of 20–50% of demand by 2050, a different and by then likely smaller denominator. Regen’s Tamsyn Lonsdale-Smith: “Credible biomethane supply estimates are way below what is needed to meet current levels of gas demand.” Whoever turns out to be closer to right, the dispute does not touch the levy. The levy compounds either way.

The real story, though, is the mechanism underneath the £190.82 million ceiling: a number up 94% in twelve months, on a floor that only compounds once locked in, disclosed in a place built so it wouldn’t be read, funding a fifteen-year commitment that nobody voted on as a single decision, because there was never a single decision to vote on. I built the UK Subsidy Clock on the premise that the government totals the cost of the energy transition nowhere — DESNZ tabulates the GGSS on its own, the Renewables Obligation on its own, the Contracts for Difference levy on its own, each in its own compliance document, and nothing anywhere adds the columns together into one number a voter could point to and ask a minister about. The GGSS is what that premise looks like in practice on the gas side of the bill. None of it is a scandal. It is routine, and it runs to 2041.

The Energy Trap: Why the Renewable Energy Transition Can’t Work — And What Can is published by Swift Press in September.