The Planning and Infrastructure Bill was introduced in March 2025 and provides new powers for the Secretary of State and Ofgem, according to the government's statutory security of supply report published on 17 December 20251. The report, prepared jointly by the Secretary of State for Energy Security and Net Zero and the Gas and Electricity Markets Authority, covers the availability of electricity and gas to meet consumer demand over the next four calendar years1.
The same report records that Ofgem's formal approval of NESO's reform proposals in April 2025 "marked a pivotal moment"1. NESO, the National Energy System Operator, is developing the Strategic Spatial Energy Plan following a commission from the Department for Energy Security and Net Zero in October 2024; the plan will set out, on a zonal basis, future required generation and storage for electricity and hydrogen, and will inform wider strategic energy planning for networks and grid connections1. The government has also said it will work with Ofgem on a review of transmission and connection charges, to give stronger incentives for investors to build generation where it is needed1.
On capacity, the report states that the T-1 auction for the delivery year 2025/2026 concluded on 5 March 2025 and secured 7.9GW of de-rated capacity at a clearing price of £20/kW per year, while the T-4 auction for the delivery year 2028/2029 concluded on 11 March 2025 and secured 43.1GW of de-rated capacity1. The report says £1.25 billion was paid out to Capacity Market agreement holders for the 2024/25 delivery year, and that the next auctions will be held in March 20261.
For this winter, NESO forecasts sufficient electricity capacity to meet demand, with a derated margin of 6.1GW (10.0%) of Average Cold Spell peak demand, up from 5.2GW (8.8%) last winter and the highest predicted margin since 20191. The report gives a Loss of Load Expectation of below 0.1 hours per year against a standard of three hours per year1. On gas, the report notes National Gas decided in June 2025 that significant volume growth from the previous year's tender would be required, and that the Interconnector has held an open season on capacity sales and reduced capacity from 73mcm/d to 61mcm/d from 4 November 20251. A Department for Energy Security and Net Zero consultation closes on 18 February 2026, and plans have been announced to reduce import capacity to 36mcm/d from 1 October 20261.
"The Planning and Infrastructure Bill, introduced in March 2025, provides new powers for the Secretary of State and Ofgem"
Why it matters for households
The bill's powers over codes, licences and strategic planning sit behind the grid connection queue that determines when new generation, storage and network capacity can connect, and therefore how quickly the system can absorb new supply1. The report's central conclusion is that GB is expected to have the ability to access and secure sufficient supplies of electricity and gas to meet consumers' demands over the short and long term1. For a household, that security of supply is the background condition for energy independence: the lights stay on and the gas keeps flowing, but the price and the carbon intensity of that supply are set by market and network arrangements the household does not control. The Capacity Market payments recorded in the report are recovered through bills, and the network charges review is intended to change where generation is built, which affects the cost of the system as a whole1. The report does not state what any of this will mean for individual household bills.
What happens next
The next Capacity Market auctions will be held in March 20261. The Department for Energy Security and Net Zero consultation on gas security of supply closes on 18 February 20261. Ofgem's approval of NESO's reform proposals took place in April 2025, and the Strategic Spatial Energy Plan is being developed by NESO following its October 2024 commission1.