Professors say today's solar eclipse won’t crash the grid — so why is Octopus Energy paying customers to switch off?

Octopus Energy warns we could face a 1.3GW solar energy shortfall thanks to today's eclipse It advises we cut energy usage today and is offering free electricity as reward Experts say "the impact of the eclipse will be limited and is well planned for" Ahead of today's solar eclipse — which is due to

<![CDATA[ <article> <ul><li><strong>Octopus Energy warns we could face a 1.3GW solar energy shortfall thanks to today's eclipse</strong></li><li><strong>It advises we cut energy usage today and is offering free electricity as reward</strong></li><li><strong>Experts say "the impact of the eclipse will be limited and is well planned for"</strong></li></ul><p>Ahead of today's solar eclipse — which is due to appear in the UK between 6pm and 8pm on Wednesday, August 12 — Octopus Energy is asking us to<a href="https://octopus.energy/press/more-news-press-releases/brits-can-earn-free-electricity-and-win-pound12-000-by-using-less-electricity-during-wednesday-s-historic-solar-eclipse/" target="_blank"> avoid using unnecessary electricity</a> as much as possible during the natural blackout. In exchange, it’ll give customers who are signed up to its rewards program a free hour of electricity to use next weekend.</p><p>Octopus argues that the eclipse will greatly reduce Britain’s solar power generation. At the same time, because of an incoming heatwave, we’ll likely be using a lot more power running refrigerators, air conditioning and fans that put an increased strain on our power grid.</p><p>If Britons are more conservative with their power consumption — especially between 6pm and 8pm when the eclipse is scheduled — and better leverage the 13GW of “untapped” flexible capacity brought about by smart appliances, EVs and home batteries, Octopus says we could reduce the need for gas-powered generators.</p><p>But do we really need to watch our electricity use this evening — and if so, why? Here's what university professors and other experts say.</p><h3 class="article-body__section" id="section-should-we-cut-our-electricity-use-during-the-solar-eclipse"><span>Should we cut our electricity use during the solar eclipse?</span></h3><p>Energy experts are a divided on exactly how much the eclipse will hit the UK's solar energy supply — but they all agree that drastically changing your electricity habits this evening isn't necessary.</p><p>"The dip in supply from solar during the eclipse could be significant, and the electricity supply companies are right to be cautious," said Chris Sansom (Professor of Concentrating Solar Power at the University of Derby).</p><p>"They have a right to be concerned because quite a significant proportion of our energy comes from solar," he added, sharing the screenshot below from yesterday at 6pm showing that 17.4% of our electricity was coming from solar.</p><figure class="van-image-figure inline-layout" data-bordeaux-image-check ><div class='image-full-width-wrapper'><div class='image-widthsetter' style="max-width:2000px;"><p class="vanilla-image-block" style="padding-top:56.25%;"><img id="uZrCZ5N852hfA92mSiWyra" name="Solarpower" alt="A laptop screen showing a UK energy mix graph" src="https://cdn.mos.cms.futurecdn.net/uZrCZ5N852hfA92mSiWyra.jpg" mos="" align="middle" fullscreen="" width="2000" height="1125" attribution="" endorsement="" class="inline"></p></div></div><figcaption itemprop="caption description" class=" inline-layout"><span class="credit" itemprop="copyrightHolder">(Image credit: NESO)</span></figcaption></figure><p>However, in the grand scheme, the amount of solar power lost to the eclipse won't enormous be due to the time of day. </p><p>Across Europe, grid operators expect a 9.7GW power generation reduction during the eclipse, while the UK’s National Energy System Operator (NESO), the body in charge of managing our electricity system, predicts we’ll lose around 0.7GW of power output that would have been generated, though it adds the loss could be as much as 1.3GW (via the <a href="https://www.ft.com/content/06a25d8d-77d8-4dd5-8cd6-a105423544b2" target="_blank">Financial Times</a>).</p><p>By 7pm, the darkest point of the eclipse, solar energy will be supplying less than 3% of our electricity demand, says Peter Connor (Associate Professor of Sustainable Energy Policy at the University of Exeter). "This drop off happens every night in the summer, and largely is met by turning on more gas power plants, which is what will happen on Wednesday night," he said. </p><p>So should we cut our electricity use? "There is no real need in terms of grid stability — if there was a possible problem it would be NESO, the system operator that would be trying to take action," added Peter Connor.</p><p>The trade association Solar Energy UK, which represents hundreds of solar photovoltaic and battery storage companies, largely agrees. "The impact of the eclipse will be limited and is well planned for — comparable to a gas or nuclear power station being shut down for regular maintenance," a spokesperson said. "As the eclipse will occur in the evening, only a limited amount of power will be lost — in the order of 0.5-0.8GW at peak," it added.</p><p>"We do not expect any undue effects on the grid from the eclipse, not least as it will happen close to sundown," Solar Energy UK CEO Chris Hewett said. “Battery energy storage will no doubt play an important role in managing the grid during the time, as it does every day,” he added.</p><h3 class="article-body__section" id="section-what-s-behind-octopus-energy-s-offer"><span>What's behind Octopus Energy's offer?</span></h3><p>Octopus Energy isn't trying to prevent a major grid outage with its 'Eclipse Power Down' offer to customers — instead, it's trying to avoid the firing up of extra gas power stations to cover any deficit.</p><p>"By requesting customers to reduce demand during the short period of the solar eclipse they are looking to reduce the possibility of having to meet any shortfall from increased gas consumption or from imports, which is an additional cost," said Professor Chris Sansom from the University of Derby.</p><p>But others think there's also an element of Octopus Energy using the solar eclipse as an experiment. "I think Octopus are interested in seeing how they can incentivise people to change their energy consumption behaviour and how big an impact they can have with the incentives they offer," said Peter Connor from the University of Exeter.</p><p>"About 50% of homes have smart meters, so you can then offer incentives for behaviour change around consumption — and if consumers like the incentives, then they can choose to use energy at different times and be rewarded for it," he added.</p><h3 class="article-body__section" id="section-what-is-the-octopus-energy-offer"><span>What is the Octopus Energy offer?</span></h3><p>The Octopus Energy 'Eclipse Power Down session' is part of the company's 'Saving Sessions' campaign to help balance grid demand.</p><p>If you're an Octopus customer, you can get the offer by signing up for <a href="https://octopus.energy/octoplus/" target="_blank">Octoplus</a> (its loyalty scheme for smart meter customers) and opting into the 'Eclipse Power Down' on your dashboard.</p><figure class="van-image-figure inline-layout" data-bordeaux-image-check ><div class='image-full-width-wrapper'><div class='image-widthsetter' style="max-width:2000px;"><p class="vanilla-image-block" style="padding-top:56.25%;"><img id="ujdQKDTLpx3gcmynNdinG9" name="OctopusEnergy" alt="A laptop screen showing an Octopus Energy eclipse electricity offer" src="https://cdn.mos.cms.futurecdn.net/ujdQKDTLpx3gcmynNdinG9.jpg" mos="" align="middle" fullscreen="" width="2000" height="1125" attribution="" endorsement="" class="inline"></p></div></div><figcaption itemprop="caption description" class=" inline-layout"><span class="credit" itemprop="copyrightHolder">(Image credit: Octopus Energy)</span></figcaption></figure><p>Octopus says it'll monitor your usage on your smart meter — and if you’ve used less electricity than you usually would during "at least half an hour of the Power Down", you’ll get a free hour of power on Sunday August 16.</p><p>You can read the full FAQ on the <a href="https://octopus.energy/eclipse/#faqs" target="_blank">official Eclipse Power Down page</a>.</p><h3 class="article-body__section" id="section-how-can-you-cut-your-energy-usage"><span>How can you cut your energy usage?</span></h3><p>The worst-case scenario is that we'll need to generate an extra 1.3GW each hour of the two-hour-long eclipse, with all of that covered by gas-fired power plants. That'd mean we're looking at around 1.04 million tonnes of C02 being released into the atmosphere. Based on last year's <a href="https://www.gov.uk/government/statistics/provisional-uk-greenhouse-gas-emissions-statistics-2025/2025-uk-greenhouse-gas-emissions-provisional-figures-statistical-release" target="_blank">emissions from energy production</a> this is just a 0.2% increase.</p><p>So how should we cut our energy use, whether we're on Octopus or not? "Not running high power-consumption domestic appliances is a good way to reduce this demand," says Professor Chris Sansom from the University of Derby. "These include tumble-driers, air fryers, electric ovens, washing machines, and dishwashers. Fridge freezers also come into that category, but no one is suggesting they should be switched off," he added.</p><figure class="van-image-figure inline-layout" data-bordeaux-image-check ><div class='image-full-width-wrapper'><div class='image-widthsetter' style="max-width:7360px;"><p class="vanilla-image-block" style="padding-top:56.25%;"><img id="g42gHhyQNTp88oiGox4Heh" name="GettyImages-1002451536.jpg" alt="energy" src="https://cdn.mos.cms.futurecdn.net/g42gHhyQNTp88oiGox4Heh.jpg" mos="" align="middle" fullscreen="" width="7360" height="4140" attribution="" endorsement="" class="inline"></p></div></div><figcaption itemprop="caption description" class=" inline-layout"><span class="credit" itemprop="copyrightHolder">(Image credit: Getty)</span></figcaption></figure><p>"Some demand is more ‘shiftable’," adds Peter Connor from the University of Exeter. "EVs are the most obvious one, but other ways people can save include putting their (clothes or dish) washing or drying on at cheap times, or using the oven at cheap times. It only matters for a consumer’s bill if they are on a tariff which lets them access cheap prices if they move their electricity consumption around," he adds.</p><p>Cutting our energy usage, or using Octopus’s methods to be more efficient with our electricity consumption — such as charging up home batteries and having smart appliances come on when renewable energy is abundant, and then discharging when we’d need fossil fuels — would certainly help on the day of the eclipse, but it’s a relative drop in the ocean of carbon we’re producing.</p><p>But if we managed to unlock even half of Octopuses’ flexible capacity to reduce our fossil fuel-created electricity demand every single day we could see a much bigger positive impact.</p><figure class="van-image-figure inline-layout" data-bordeaux-image-check ><div class='image-full-width-wrapper'><div class='image-widthsetter' style="max-width:8192px;"><p class="vanilla-image-block" style="padding-top:56.25%;"><img id="yv89x6LL6fgFPa8t2ABFN9" name="GettyImages-2169877472" alt="A balcony solar panel" src="https://cdn.mos.cms.futurecdn.net/yv89x6LL6fgFPa8t2ABFN9.jpg" mos="" align="middle" fullscreen="" width="8192" height="4608" attribution="" endorsement="" class="inline"></p></div></div><figcaption itemprop="caption description" class=" inline-layout"><span class="credit" itemprop="copyrightHolder">(Image credit: Getty Images / Sean Gallup)</span></figcaption></figure><p>Gas-fuelled plants (the only fossil-fuel plants the UK relies on) produced around 30% energy production needs on average (8.5GW) <a href="https://grid.iamkate.com/" target="_blank">in the past year</a>, meanwhile just half of Octopus' flexible capacity would cover 6.5GW.</p><p>The answer is, of course, we should do both — cut our energy demands for the eclipse, and be more efficient going forward. Because the problem of fossil fuel emissions wrecking our climate is a solvable one, we just have to take action in the face of every problem — not just big dark celestial ones.</p> </article> ]]>