Just over a decade ago, coal was the backbone of the UK’s energy system, supplying nearly 40% of electricity in 2012. Today, it’s gone, replaced by cleaner, greener alternatives.

In 2012, the UK generated 143 terawatt-hours (TWh) of electricity from coal. By 2023, that number had plummeted to almost zero. In its place, wind and solar power surged, growing from just 6% of the energy mix 2012 to 34% last year.

Wind power was the star of this transformation, with output increasing by a staggering 315%. The result? A cleaner, greener, and more resilient power system.

Power sector emissions fell by 74%, avoiding an incredible 880 million tonnes of CO₂.

This transformation wasn’t just about shutting down old coal plants. It was about building a new system.

Policies like a rising carbon price made coal uneconomical by 2015. At the same time, government support gave renewables a significant boost.

Programs like the Offshore Wind Sector Deal and Contracts for Difference ensured investors backed wind and solar projects. Meanwhile, big investments in the grid helped new renewable projects come online faster and more efficiently.

The work isn’t over. The UK is now targeting a fully clean power system by 2030. That means quadrupling offshore wind, tripling solar power, and doubling onshore wind. By then, natural gas will provide just 2% of electricity as a backup.

But challenges remain. Electrifying homes and transport will push the demand for electricity higher.

Delays in connecting new renewable projects are holding things up. And the UK needs more battery storage to balance the growing renewable grid.

In just over a decade, the country went from relying on coal to leading on renewables. Along the way, it cut emissions, reduced costs, and proved that cleaner energy doesn’t mean weaker reliability.

“This is a huge milestone,” said Frankie Mayo, a senior energy analyst at Ember. “The UK has achieved something incredible. But there’s more work to do.”