Eclipse drives UK power prices to two-month highs
A rare solar eclipse and a summer heatwave have created a supply squeeze in Great Britain, pushing wholesale electricity prices to June levels and triggering costly interventions from the grid operator.
Great Britain’s electricity system operator is securing extra generating capacity for Wednesday evening after a near-total solar eclipse wiped out a significant portion of the country's solar power. The supply squeeze pushed wholesale prices to levels not seen since late June.
The National Energy System Operator (Neso) initially warned of a shortfall exceeding 1,700MW—the equivalent capacity of a solar farm spanning 8,500 football pitches—before revising the deficit to roughly 1,200MW on Wednesday morning. The loss of between 300MW and 1,100MW of solar generation is colliding with the fifth heatwave of the summer, which has lifted demand for air conditioning and refrigeration.
The price of electricity for Wednesday evening spiked to more than £211.40 per megawatt-hour at 7pm, according to LCP Delta. To bridge the gap, Neso is expected to make lucrative payments to other generators, particularly gas-fired power plants. If elevated market prices persist, gas operators stand to secure highly profitable contracts. These additional balancing costs are ultimately covered through consumer energy bills.
Neso moved to calm markets, issuing a warning late on Tuesday that was updated on Wednesday morning. A spokesperson described the notice as a “routine tool” and a “precautionary measure to the market”, adding there was “no risk to customer electricity supplies”.
The event highlights the vulnerability of the British power grid to simultaneous shocks to renewable supply and temperature-driven demand. While system operators focus on grid stability, the financial mechanics of the balancing system mean investors in flexible gas generation are poised to benefit from short-term price volatility.
Octopus Energy, Britain’s biggest household electricity provider, is attempting to mitigate the squeeze on the demand side. The company is offering eligible customers a free hour of Sunday electricity if they avoid using washing machines and dishwashers between 6pm and 8pm on Wednesday. Broad participation could reduce the need to fire up expensive gas-fired stations to replace the lost solar power.
