Britain was forced to pay exceptionally high prices for emergency electricity imports during this week’s heatwave after domestic power supplies failed to meet demand, raising fresh questions about the country’s energy security and the resilience of its electricity system.
Data from the National Energy System Operator (NESO) show that on Wednesday evening the UK paid up to £1,379 per megawatt hour for imported electricity under emergency balancing arrangements. Wholesale electricity prices are typically around £80 per megawatt hour, meaning the emergency imports cost around 17 times more than normal market prices.
Industry estimates suggest the additional balancing measures added around £11 million to electricity system costs in a single evening.
The emergency imports were required after electricity demand increased significantly during the hot weather, with greater use of air conditioning in offices, shops and commercial buildings. At the same time, domestic electricity generation was lower than expected, with reduced output from some solar installations and several gas-fired and nuclear power stations unavailable.
NESO secured additional electricity from neighbouring European countries, principally the Netherlands, after obtaining special permission under existing cross-border arrangements.
Energy analysts have suggested demand during the heatwave exceeded forecasts by as much as three gigawatts — broadly equivalent to the output of three nuclear power stations.
Consultancy Watt Logic argued that forecasting errors left the electricity system relying on emergency measures, while analysts at Montel said rising temperatures are changing electricity demand patterns and may require different planning assumptions in future.
Several gas-fired power stations were already offline for scheduled summer maintenance, while four of Britain’s remaining nuclear reactors were unavailable because of planned and unplanned outages.
The heatwave also coincided with a period of relatively low wind speeds across much of Europe. Solar generation was also affected, as photovoltaic panels become less efficient during very high temperatures. Across Europe, some nuclear stations also reduced output because rivers used for cooling became unusually warm.
NESO said it successfully maintained a secure electricity system throughout the period by using established operational procedures and existing agreements with neighbouring transmission operators.
Energy security debate intensifies
The incident has reignited debate over Britain’s long-term energy strategy and whether the country has become too dependent on imported energy during periods of peak demand.
The Labour Government has halted the issuing of new oil and gas exploration licences in the UK North Sea, arguing that future energy policy should focus increasingly on renewable generation while existing licensed fields continue production.
Critics argue that reducing domestic production does little to reduce overall fossil fuel consumption if Britain continues importing oil and gas from overseas.
Supporters of expanded North Sea production point out that Norway continues to develop its own North Sea oil and gas resources, exporting significant quantities to the UK. They argue that importing hydrocarbons over long distances from countries such as Russia, the US and Qatar result in higher transport emissions than producing energy from fields much closer to Britain’s shores.
Industry groups have also argued that domestically produced gas can improve energy security by reducing reliance on international markets during periods of global disruption or unusually high demand.
The Government maintains that expanding renewable energy generation, alongside investment in electricity networks and storage technologies, will strengthen Britain’s long-term energy resilience while helping meet legally binding climate targets.
However, this week’s events are likely to intensify calls from supporters of domestic oil and gas production, who argue that Britain should make greater use of its own natural resources rather than paying premium prices for imported energy when domestic generation falls short.
As demand for electricity continues to rise through the electrification of transport, heating and industry, questions over how Britain guarantees reliable, affordable and secure energy supplies are likely to become an increasingly prominent political issue.
