The price cap will rise by £63 in October, the third increase this year, but Ofgem has just opened a door to longer-term savings. On 24 September 2024, the regulator announced it had selected 16 long-duration electricity storage projects for accelerated development, as reported by Enerdata. These projects, mostly compressed air, liquid air, and flow batteries, can store power for four hours or more, unlike the typical two-hour lithium-ion batteries dominating the market. The catch is that none will be operational before 2030. But for UK homeowners, the long-term prize is real: lower bills, a greener grid, and more predictable energy costs.
How long-duration storage cuts your electricity bill
Britain wastes roughly 5% of its renewable generation each year, enough to power 2 million homes, because the grid has nowhere to store it when the wind blows at 3 a.m. Ofgem’s 16 projects aim to capture that surplus. When the wind drops and gas plants fire up, stored renewable power can replace expensive gas-generated electricity, especially during the 4 p.m.–7 p.m. peak. Energy Systems Catapult modelling suggests that widespread long-duration storage could shave 10–20% off wholesale electricity costs. For the typical household using 2,900 kWh a year, that translates to £30–£60 off the annual bill. Not a revolution, but a meaningful dent in the £1,717 price cap.
Who qualifies, and who doesn’t
These are grid-scale projects, not household batteries. You cannot install one in your loft. But the benefit flows to every home connected to the national grid. Homes with solar panels or heat pumps stand to gain most: a more stable grid means fewer export constraints and lower running costs for heat pumps, which draw heavily during winter evenings. Ofgem has prioritised projects in Scotland, Wales, and northern England, where renewable capacity is highest. If you live in those regions, you may see local grid improvements sooner. The regulator has also committed to a second round of projects, so the list may grow.
What it means for your EPC and home upgrades
A cheaper, greener grid changes the economics of home energy upgrades. Right now, a heat pump costs roughly £600–£800 a year to run on a variable tariff. If storage cuts peak electricity prices by 15%, that drops to £510–£680. The payback period on a £12,000 heat pump installation shortens by about two years. Similarly, solar panels become more attractive: you can export surplus power at higher prices when storage soaks up midday generation. The Energy Saving Trust estimates that a typical 3.5 kWp solar system could earn an extra £50 a year from export tariffs if storage stabilises prices. For EPC ratings, the impact is indirect but real: lower running costs improve the ‘cost’ component of the rating, and a heat pump or solar array can add 5–15 points to your score.
What to do now
The first 16 projects are at the ‘gateway’ stage, developers must now secure planning permission, grid connections, and financing. Ofgem expects the first units to connect by 2028–2030. Homeowners on standard variable tariffs can prepare by switching to a time-of-use tariff, such as Octopus Flux or OVO Beyond, which already reward off-peak consumption. Check your EPC rating at gov.uk, if it’s below C, consider insulation and draught-proofing first, as storage savings are modest without a well-sealed home. For those planning a heat pump or solar array, wait until 2025 when the next round of the Boiler Upgrade Scheme opens, but start quoting now. The storage revolution is coming, but it will arrive in your bill, not your boiler cupboard.
Frequently Asked Questions
No. The first projects are unlikely to be operational before 2028–2030. However, you can benefit sooner by switching to a time-of-use tariff that rewards off-peak consumption, which storage will make cheaper.
No. Grid-scale storage lowers wholesale prices for everyone. But if you already have solar panels, a home battery can help you store your own surplus and avoid buying expensive peak-time power, amplifying the savings from a cheaper grid.
