In its summer outlook report, Britain’s electricity grid operator said it was expecting its lowest-ever electricity demand thanks to renewables and cheap power imports from Europe.
National Energy System Operator (NESO)’s 2025 Summer Outlook sets out operational expectations for the summer months on Great Britain’s national electricity transmission network.
NESO said it expected electricity demand could drop to 13.4GW at some points—less than in June 2020 when COVID-19 pandemic lockdowns suppressed electricity demand below normal summer levels.
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“As with previous summers, we expect there to be sufficient electricity supply to meet demand and operational reserve requirements across the summer. We’re confident that we have the right tools in place to operate the network over the summer months,” NESO’s statement read.
“There is potential that we may need to use these operational tools such as Negative Reserve Active Power Margin (NRAPM) notices to inform the wider energy market of periods where greater flexibility will be required to balance the electricity network.
“Growth in renewable generation, particularly solar will likely see a reduction in the electricity transferred across the national electricity transmission network.”
Already this year, multiple records for maximum solar generation have been set in March and April, with the record currently standing at 12.68GW—greater than Britain’s total import capability across the European interconnectors.
Internationally, the growth in renewable generation coupled with healthy availability from conventional power stations is expected to drive the direction of interconnector flows across cables between Britain and mainland Europe, with Britain largely importing cheaper surplus electricity from its European neighbours across the summer.
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Operating at low demands requires careful balancing by NESO engineers to ensure that supply does not outstrip demand, while also ensuring that the national electricity network receives a minimum continual flow of electricity to maintain its optimal operation.
NESO director of resilience and emergency management Dr Deborah Petterson said, “One of the great engineering challenges of decarbonisation is managing our system when there is lower demand coinciding with higher levels of generation from renewable sources.
“So, to deliver our 2025 zero carbon ambition we have made great progress re-engineering how we operate the national electricity network. These innovations will not only further increase the resilience of Great Britain’s national electricity network but will also deliver economic benefits in balancing the system by improving the flexibility and competitiveness of running the electricity network at low demand.”
