Winter Blackout Risk Rises as UK Power Buffer Shrinks
Britain’s National Energy System Operator forecasts a smaller reserve margin for winter than last year, even as it says supplies are expected to remain secure…
Britain’s winter power reserve is shrinking, renewing questions about how much protection the grid has during cold weather. The winter blackout risk rises for the first time in four years, the National Energy System Operator said, although it expects supplies to remain secure.
The operator, known as Neso, forecast a power buffer of 5.9 gigawatts, or 9.5pc of demand. Last year, its forecast was 6.1GW, or 10pc. The lower margin is the first decline in the projected spare power available during a cold spell since the outbreak of the Ukraine war in 2022.
The figures do not mean blackouts are expected. Neso said electricity supplies were “sufficient for the forthcoming winter” and “expected to remain secure.” But the forecast highlights the conditions behind that assessment, including demand, generation reliability and access to power from neighbouring countries.
Jonathan Brearley, permanent secretary at the Department for Energy Security and Net Zero, told MPs the Government could not guarantee uninterrupted supply. “We can never guarantee the lights won't go out,” he told members of the public accounts committee. “As you know, there are always risks in any system.”
Winter blackout risk rises as demand squeezes margin
Neso said increased electricity demand had narrowed the forecast buffer. It pointed to energy-hungry data centres as a possible source of growth, alongside more households adopting electric cars and heat pumps.
There is a change in how the reserve is calculated, too. This winter’s figure uses a different methodology from last year’s, assigning wind farms a higher level of reliability. Under the previous method, the margin would have been 5.2GW, or 8.4pc of demand.
Britain’s total power-generation capacity has risen from 127GW to 137GW in the past year. Neso said much of that increase came from renewables, which it described as less reliable than gas and nuclear power. That means the added capacity does not automatically translate into a larger safety cushion.
The distinction matters for households and businesses because the forecast margin measures spare supply against demand, not simply the total amount of generating capacity. Neso’s assessment also assumes Britain can draw on electricity imports from European neighbours. Without those imports on the coldest winter days, the margin would be wiped out, according to the source report.
Grid security and the clean-energy transition
The outlook comes after an independent report earlier this week warned that Neso control-room engineers were concerned the switch to renewable energy was making the grid harder to manage. The report said they felt pressure to “convey a positive message.”
Neso’s forecast offers a more reassuring public assessment. Deborah Petterson, the operator’s director of resilience, said Britain had a “resilient and well-prepared electricity system” despite geopolitical uncertainty and volatility in global energy markets. She said its outlook showed sufficient margins and a diverse mix of generation to meet demand during colder weather and periods of higher system stress.
Brearley also told MPs the Government may struggle to upgrade the grid sufficiently by 2030 to meet its pledge to power Britain with clean energy. He said responsibility for delivering network upgrades on time ultimately rests with transmission companies, while acknowledging that some risks sit beyond government or company control.
Tim Jarvis, chief executive of energy watchdog Ofgem, acknowledged the concern when pressed on the issue. “We accept there is risk there,” he said.
A separate winter outlook from National Gas also forecast secure supplies, while warning that prices might surge. Neso’s forecast reserve remains 5.9 gigawatts.
Source: yahoo.com
