UK Grid Operator Warns of Tight Power Margins in Heatwave
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- Neso issued an overnight electricity margin notice warning of "tight electricity margins" during Thursday evening's peak period, citing "extreme temperatures across Europe, reducing the availability of some generation," while insisting "there is no risk to customer electricity supplies."
- Neso requested extra generation and flexibility from power providers to cope with added demand from fans and air conditioners, raising the prospect of the operator paying "much higher than average prices to gas power plants."
- EDF warned the heatwave is straining its French nuclear reactors, with output potentially curbed at up to five plants as hot river water hampers cooling — starting with a two-reactor reduction this week, with more slowdowns possible as the heatwave moves across the continent.
- Parts of southern England are forecast to hit 34C on Thursday, with hot weather dragging out over 10 days, though temperatures are expected to stay below the provisional June record of 37.7C set at Lingwood, Norfolk on June 27.
- France has seen 35,400 hectares burn from wildfires so far — double the average — while Spain has lost 55,128 hectares, according to the European Forest Fire Information System, as Western Europe enters its third heatwave in six weeks.
- Neso last issued similar pleas during the previous heatwave just weeks ago, when the UK recorded its highest-ever June temperature of 37.7C, breaking a 1976 record of 35.6C.
Why it matters: Neso's notice signals simultaneous strain on both the UK's backup gas generation and its cross-Channel nuclear imports from France, where EDF is curbing output at up to five reactors — meaning the grid may lean more heavily on expensive gas-fired power during a 10-day heatwave with no customer outages expected but margin to spare shrinking.
