Britain’s electricity demand has risen for the second consecutive year after two decades of decline, marking a turning point as electric vehicles, heat pumps, and AI-powered data centres reshape energy use.
Provisional figures for 2025 show electricity consumption climbed by 3%, the fastest annual increase since 2001, according to analysis by Imperial College London for Drax Electric Insights. Electricity use reached an estimated 273 terawatt-hours (TWh) this year, up from 266 TWh in 2024 and 262 TWh in 2023. Demand had previously peaked at 347 TWh in 2005 before steadily falling due to more efficient appliances, declining heavy industry, and deindustrialisation.
“We have reached a turning point after 20 years of demand falling,” said Iain Staffell, associate professor of sustainable energy at Imperial College and lead author of the analysis. “Electric vehicles, heat pumps and the data centres powering AI are now pushing up electricity demand.”
The increase reflects rapid electrification across transport, heating, and digital infrastructure. Installations of heat pumps rose by around 20% in 2025, while electric vehicle sales jumped 28%, with roughly one in three new cars sold now fully electric. Meanwhile, electricity use by data centres has doubled since 2020, accounting for 3–4% of national consumption, with projections suggesting it could exceed 10% within a decade.
The rise in demand comes amid government efforts to decarbonise the energy system. The Climate Change Committee has warned that electricity demand may need to at least double by 2050 to meet net-zero targets, prompting plans to expand generation capacity and upgrade the national grid at a cost of tens of billions of pounds.
The extra electricity in 2025 was supplied entirely by cleaner sources. Renewable generation rose sharply, led by a 35% surge in solar output following the sunniest year on record and the commissioning of new solar farms. Solar contributed 7% of total generation, while wind remained the largest source at 31% for the second year running. Gas-fired plants provided 28%, while nuclear output fell to just 12%, its lowest share since 1980, after extended maintenance and unplanned reactor shutdowns.
“Our power system got cleaner at the same time as growing,” Staffell said. “Renewables met all the extra demand placed on the grid.”
Carbon emissions from electricity generation fell to their lowest level since 1938 following the closure of the last coal-fired power stations in 2024. However, wholesale electricity prices rose 12% over the year, driven by higher gas costs and rising carbon prices.
The data highlight a fundamental shift in the UK energy system: rising electricity demand is now being driven not by inefficiency, but by the transition away from fossil fuels. Analysts warn that the key challenge will be scaling generation, networks, and storage fast enough to meet demand without sharply increasing costs for households and businesses.
