The UK must significantly expand energy storage to achieve its clean power system target by 2030, as a tenth of wind-generated electricity is currently wasted,.
A report by Drax and Imperial College London highlights that last year, wind power became the UK’s largest electricity source (31%), surpassing fossil fuels for the first time in 140 years.
However, 8.3 TWh of wind energy—enough to power two million homes—was lost due to grid congestion, costing consumers nearly £400 million.
Investing in long-duration energy storage (LDES) and battery energy storage systems (BESS), alongside grid improvements, could store surplus wind power and release it when needed, reducing reliance on gas during low-wind periods.
Without urgent investment and policy support, the country risks wasting substantial clean energy.
Historically, Britain’s power generation was dominated by coal until the 1980s, when gas took over. Now, 2024 marks the first time a renewable source leads electricity production, signaling a shift in the UK’s energy landscape.
”The rapid and continued growth of wind power gives us grounds for optimism on the journey towards clean energy, but that growth presents its own very real and different challenges” says Dr Iain Staffell of Imperial College London, the lead author of the report.
“Last year we saw a 17% reduction in emissions compared to 2023 but with more wind comes more intermittency. This was evident throughout the winter of 2024 and into 2025, with three separate periods of cold, calm weather – known as ‘dunkelflaute’ – exposing Britian’s reliance on costly imported energy and drawing down the nation’s gas storage to ‘concerningly low’ levels.
Investment in intermittent renewables such as wind and solar is helping us reduce fossil fuel levels in our power generation mix but without large-scale energy storage and grid upgrades, we will continue wasting clean energy and paying the price for it, especially during long cold snaps and windless conditions.”
Dr Iain Staffell, Imperial College
With upgraded energy storage and the transmission infrastructure to transport it, the report finds we can stop renewable energy wasted. Instead power could be moved to where it is needed as well as storing it until it’s needed.
Wasted wind
The curtailment of wind energy – where turbines are shut down when there is no capacity to transport their power – is rising at an unsustainable rate.
In just one year, curtailment doubled from 5.5% to over 10%, largely due to Scotland’s wind farms producing more energy than the grid can carry south to demand centres in England.
Ian Kinnaird, FlexGen Assets Director at Drax commented: “The UK government has set ambitious targets for energy storage and grid reinforcement, but the pace of deployment must accelerate to match the rapid growth of renewable generation.
“Policy incentives, streamlined planning processes, and investment in medium and long-duration storage technologies will all be critical in ensuring Britain fully capitalises on its renewable energy sources.”
To access the full report, visit Drax Electric Insights.
