The UK government has pushed through a fresh set of capacity market amendments, with the Electricity Capacity (Amendment and Transitional Provision) Regulations 2026 made on 16 July 2026, approved by both Houses of Parliament, and brought into force on 17 July 2026. Signed by Energy Minister Michael Shanks and published on legislation.gov.uk, the rules extend across England and Wales and Scotland. On paper, this is a technical update to existing electricity law. In practice, it matters because the capacity market is one of the tools used to keep power available when demand is high and supply is tight. For a grid taking on more wind, solar and electrified demand, those market rules help decide whether Britain gets reliable back-up power at a fair price.

The capacity market pays providers for committing electricity capacity that can be called on during system stress events. In Great Britain, that can include generation assets and demand-side response, with the National Energy System Operator running prequalification and auctions, and the Electricity Settlements Company making payments funded through supplier charges. This instrument amends three strands of existing law: the Electricity Capacity Regulations 2014, the Electricity Capacity (Supplier Payment etc.) Regulations 2014 and the Electricity Capacity (No. 1) Regulations 2019. The government note says the aim is to improve the operation of the current scheme rather than redesign it. Even so, the changes sharpen who can enter auctions, how much financial backing they must show and what happens when a project fails to deliver.

The clearest shift is tougher financial discipline. The regulations expand the termination fee structure from five bands to nine and add new rates of £6,500, £13,000, £19,500 and £45,500 per MW, while retaining the existing higher band in the regime. In simple terms, the government is raising the cost of failing to follow through on a capacity market commitment. Credit cover is rising too. Some applicant thresholds move from £5,000 to £6,500 per MW, while others rise from £10,000 to £13,000 per MW. A new build project that still has not met its financial commitment milestone 12 months after auction results must raise cover to £19,500 per MW, before dropping back to £13,000 per MW if the milestone is later met. The Delivery Body can also require a further increase to £45,500 per MW in certain cases, with only 15 working days to provide it. Applications made before 17 July 2026 are protected by transitional rules that keep the earlier thresholds. That will frustrate speculative bids, but it should also favour projects that are genuinely buildable and better shield consumers from paying for capacity that never arrives.

The insolvency rules have been tightened as well. If a capacity provider receives a termination notice because of an insolvency event, the Settlement Body must stop monthly capacity payments from the date of that notice and withhold credit on a pro-rata basis for the relevant month. If the notice is later withdrawn, the withheld amount must be paid back using a matching formula. This is dry legal drafting, but it addresses a real weakness. A power system moving through rapid change needs orderly rules for failure, not just incentives for new investment. When a provider runs into financial trouble, the market has to respond quickly enough to protect billpayers, while still leaving room to correct a notice that should not have been issued in the first place.

Another useful clarification sits where the capacity market meets Contracts for Difference, the support scheme used for low-carbon generation. The legislation keeps the basic principle intact: a project should not benefit from overlapping support under both schemes for the same period. But it now draws a clearer line between direct award CFDs and allocation round CFDs, and it allows some applicants to prequalify where a CFD has been signed but the support period will start only after the capacity agreement ends. That matters because revenue support needs cleaner boundaries as the electricity system matures. Where a direct award CFD exists, an applicant can stay eligible only if it provides a non-support confirmation by the close of the prequalification window, confirming that CFD payments will not apply during the relevant delivery period. For clean power developers, that is a practical improvement. It reduces avoidable uncertainty and helps projects move from one support framework to another without double counting public money.

The regulations also deal with the machinery that keeps the scheme running. Auction guidelines must now be published not just before the prequalification window opens, but also as soon as reasonably practicable after any extension to that window made under the rules. The government note says this is designed to cover severe problems with the IT portal used for applications. On supplier payments, Ofgem is given room to direct an alternative timetable for monthly and annual reconciliation runs, with scheduled calculations able to start 7, 30 and 84 working days after the end of the relevant month or year. If the timetable changes after publication, the Settlement Body must reschedule and publish a revised version. It is administrative work, but accurate reconciliation still matters. Errors in settlement feed through to suppliers, affect confidence in the scheme and can raise the cost of financing the reliable capacity the grid depends on.

There is also some straightforward tidying up. Redundant provisions in the 2019 regulations on supplier charge payments during the standstill period are being removed, and the government says no new impact assessment has been prepared because the original capacity market was already assessed and these amendments are expected to have only minor effects on business, with no foreseen effect on the voluntary or public sector. That official view may be right in a narrow legal sense, but the wider energy story is bigger than that. Britain's electricity transition will depend not only on building more renewables, but also on whether the market rules reward dependable capacity, prevent overlap between support schemes and deal quickly with weak projects. Capacity market reform will not decarbonise the grid on its own. What it can do is make the system firmer, fairer and better prepared for a power mix that relies on clean generation backed by credible flexibility. The government note says matching amendments to the Capacity Market Rules took effect at the same time, so the next test will come when developers, suppliers and investors apply these changes in the next auction cycle.