The Big Headlines From the IEA's Global Energy Review 2026

The world's energy system shifted in a measurable way last year.

For the first time on record, a renewable energy source (namely solar) contributed the largest single share of global energy demand growth.

This earth-shaking statistic comes from the International Energy Agency's Global Energy Review 2026, a report published earlier this month that reflects on the figures from 2025.

Solar power alone met more than a quarter of the world's additional energy needs in 2025, a milestone that would have seemed fairly implausible a decade ago.

The picture of overall global energy demand shifted significantly too. 

While demand grew by 1.3% last year, that rate of growth represents a notable slowdown from the 2% recorded in 2024.

That, in part at least, was a result of a combination of cooler temperatures in key markets, modest improvements in energy efficiency and slower economic expansion in some energy-intensive sectors.

Solar breaks records, but coal and gas still dominate

The headline figure for solar is striking: generation from the technology rose by a huge 600TWh in 2025, the largest single-year increase ever recorded for any electricity source outside of post-crisis recovery periods.

That growth alone covered roughly 70% of the global increase in electricity generation.

However, the broader picture is more nuanced than the success of solar.

Coal remained the largest single source of electricity worldwide in 2025, still accounting for 34% of global generation, and global energy-related CO₂ emissions rose again – reaching a new record of nearly 38.4 billion tonnes, up 0.4% on the previous year.

Natural gas was the biggest contributor to that emissions increase, responsible for around 85 million tonnes of the 185 million tonnes rise in combustion-related CO₂.

Regional splits deepen

The US bucked a decade-long trend in a way that will unsettle climate advocates.

Energy demand in the country rose by more than 2% in 2025 – the second fastest increase since 2000, excluding post-recession years. 

That was caused in part by a harsh winter, as well as strong industrial activity and surging electricity consumption from data centres, which alone accounted for roughly half of all US electricity demand growth.

Higher natural gas prices also prompted a switch back towards coal in electricity generation, pushing US coal demand up by 10% after years of decline.

China, meanwhile, saw its coal-fired electricity generation fall for only the second time since the 1970s, as renewables and nuclear expansion outpaced demand growth.

Elsewhere, India recorded near-flat CO₂ emissions for the first time since the 1970s, though the IEA attributes much of that to a particularly strong monsoon season rather than structural change alone.

EV sales cross 20 million threshold

The world of sustainable mobility saw significant changes too.

Electric vehicle sales exceeded 20 million units globally in 2025, with one in four new cars sold being electric.

In China, that figure crossed 50% of annual car sales for the first time.

In terms of demand, Europe overtook China as the fastest growing major EV market, with sales rising 30% across the EU.

Across the Atlantic, however, the US saw a 2% decline in sales, which is likely a result of US President Donald Trump’s decision to remove federal tax credits in the second half of the year.

Battery storage surges, nuclear steadies

When it comes to climate tech, battery storage emerged as the fastest growing power technology, with 108GW of new capacity deployed globally, representing a 40% increase on 2024.

Nuclear capacity, by contrast, held steady at 420GW after 3GW of new additions was offset by retirements.

That said, construction began on more than 12GW of new nuclear capacity during the year, with several key markets like the UK signalling growing interest in nuclear power.

A structural shift?

The IEA calculates that deployment of solar, wind, nuclear, electric cars and heat pumps since 2019 now avoids more than 35 exajoules of annual fossil fuel demand, a number equivalent to around 7% of global fossil fuel use.

That is a significant number.

But with CO₂ still rising and coal still powering a third of the world's electricity, the gap between the pace of clean energy deployment and the scale of what is needed remains uncomfortably wide.

Meanwhile, it is impossible to read the IEA’s report without thinking of how the situation will appear in a year’s time, given the upheaval engendered by the ongoing conflict in the Middle East and the disruption to oil and gas supplies that has followed.

As Fatih Birol, the Executive Director of the IEA says: "In a rapidly shifting landscape, countries that prioritise resilience and diversification will be best placed to manage volatility and deliver secure and affordable energy ahead."