The rapid expansion of renewable energy is being used to meet rising electricity demands rather than displacing fossil fuels, according to new research by the University of Sussex.
Energy-hungry artificial intelligence data centres and greater use of air conditioning in a fast-heating world are among several factors threatening to undermine the climate gains made by renewables, according to the paper published in Nature Reviews Clean Technology.
Researchers from Sussex and Vienna's Central European University found record growth in solar power in the first three quarters of 2025. For the first time this rise in clean electricity outpaced global growth in electricity demand, yet the researchers warn this fragile balance is now starting to tip back the other way.
Since the 2015 Paris Agreement, which aims to limit global temperature rises, global wind and solar power generation has grown rapidly, yet emissions from the power sector have continued to rise as electricity demand has grown even faster. Analysis of global energy demand in 2025 found artificial-intelligence data centres are a major driver, alongside increased use of air conditioning as people struggle to cope with hotter temperatures.
Electrification of transport and consumer trends such as bigger cars were also highlighted as culprits. The report found these pressures are eroding efficiency gains made by individual countries. Projections to 2030 warn that increases in electricity use could consume most new renewable supply unless proactive measures are taken to limit demand.
"Renewables are scaling at record speed, but demand growth from data centres, cooling and transport is running just as fast," said Professor Felix Creutzig, Bennett Institute Chair at the University of Sussex. "We need policies that curb unnecessary energy use and shape demand so that clean electricity can have the intended effect of cutting emissions from fossil fuels."
The report cites evidence from the European Union and major cities showing that demand reduction isn't necessarily a matter of human hardship, and can coincide with economic growth and wellbeing for citizens through efficiency measures and urban planning that reduces dependence on cars. The authors conclude that aligning renewables with demand-side strategies is now central to meaningful decarbonisation.
The University of Sussex's Bennett Institute for Innovation and Policy is hosting its annual Research Symposium on 19 February. Under the theme Zero Hour for Energy Policy: Researching the Race to Net Zero delegates will explore pressing issues that underpin the acceleration of climate change policies. Attendance is free, but registration is required.
