Octopus Energy, the UK's largest energy supplier, has advised its eight million customers to reduce their electricity consumption during the upcoming solar eclipse. The company is asking customers to postpone using high-demand appliances such as washing machines, ovens, and dishwashers between 6 p.m. and 8 p.m. on the day of the eclipse.
This request comes as the moon is projected to obscure over 90 percent of the sun above the UK during that period, a level of coverage not seen since the 1999 total solar eclipse. The National Energy System Operator anticipates that the eclipse could reduce solar power generation by up to 1.3 gigawatts, enough to power approximately 500,000 homes. This reduction occurs at a critical time when electricity demand typically rises as people return home from work.
To mitigate the strain on the national grid, Octopus Energy is encouraging customers to voluntarily lower their energy usage. The company stated that reducing this demand could lessen the need to activate extra gas-fired power stations, thereby decreasing carbon emissions. As an incentive, customers who use less electricity than their usual consumption during the two-hour window will be eligible for one hour of free daytime electricity on the following Sunday. Usage will be monitored via smart meters, and qualifying customers will be notified via email.
Rebecca Dibb-Simkin, Octopus's chief customer officer, highlighted the challenge: "As the sun disappears, so will some of Britain's solar generation, just as demand peaks." She added that by shifting tasks like running a washing machine or dishwasher, households can help "reduce the need for gas power stations – and earn rewards for doing their bit."
Solar power recently accounted for a record 14.4 percent of Britain's electricity generation last month, underscoring the impact a few hours without sunshine can have on filling the energy gap. Octopus is also running a photo competition for customers to share their eclipse-day activities, with prizes including free solar panel installation or a cash alternative of £12,000.
The National Energy System Operator has been planning for the eclipse for over a year to maintain grid stability. The eclipse will be most visible in Devon, Cornwall, and western Pembrokeshire, where it will obscure 94 to 96 percent of the sun. Cities like Plymouth are expected to see 94.66 percent coverage at 7:16 p.m.
Other parts of the UK will experience slightly less coverage, with areas like Cardiff seeing 93.24 percent at 7:13 p.m., Belfast 93.09 percent at 7:08 p.m., Birmingham 91.79 percent at 7:12 p.m., and London 91.41 percent at 7:13 p.m. The easternmost parts of the UK, including coastal areas of Norfolk, Yorkshire, and the Orkney and Shetland Islands, will see the least coverage, between 88 and 90 percent.
Authorities have also cautioned the public about safe viewing practices. Eye doctors have strongly advised against looking directly at the sun without proper protection, as even brief exposure can cause lasting vision damage. Only specially certified solar eclipse glasses (ISO 12312-2) are recommended for viewing. Standard sunglasses, even dark ones, are not sufficient and can increase the risk of retinal damage by reducing glare, encouraging longer viewing times.
The next time a solar eclipse will offer such significant coverage in the UK is in 2081, with a total solar eclipse not expected until 2090. In other parts of the world, total eclipses will be visible in Reykjavik, Iceland, and several Spanish cities, including A Coruna, Oviedo, Zaragoza, Bilbao, and Valencia.