Great Britain Is Leaving the Coal Age—For a Whole Day

Update: At 11pm BST on April 21, the National Grid announced that Britain had gone 24 hours without coal. 

Gas—with less than half the carbon emissions of coal – was the single biggest source of energy throughout the day, according to the National Grid.

The UK is poised to go an entire day without using any energy from coal sources, according to British electricity network National Grid—the first time Britain will have done so since the late 19th century.

Britain's reliance on coal has been falling steadily since the 1950s and peak coal production, some 287 million tonnes, occurred way back in 1913. But at around 11pm tonight, the UK is expected to witness an entire 24-hour period passing without electricity generated by coal, as alternative power sources such as wind, solar, and nuclear become more popular and the warming months reduce electricity demand in the country.

The 24-hour milestone came very close to being reached on April 20, when there were at least 19 hours without power from coal, the National Grid said on Twitter, but tonight should see the first working day the UK hasn't needed coal power since the Industrial Revolution.

This isn't the first time coal has dropped off the map in terms of the UK's energy mix. The amount of electricity generated from coal fell to zero at various points last year. These periods amounted to a total of 200 hours when no coal was used for energy production in 2016, Dr Iain Staffell, lecturer on sustainable energy at Imperial College London, told Motherboard.

"We have retired half of the country's coal capacity in the last three or four years," explained Staffell, pointing out that the government plans to phase out coal power altogether by 2025.

"Even without that policy intention, probably nearly all of [the power stations] would have been retired anyway because we haven't built any new ones in a long time," he said.

Read more: Remember, Coal Spills Can Ruin Everything Too

The latest government figures also reveal a startling drop in the amount of coal being produced in Britain. In fact, production halved between 2015 and 2016. Imports are falling, too, and coal stocks at the end of 2016 had reached "a record low".

The importance of coal in the UK power economy may have dwindled quickly of late, but it may still have a part to play in the future, Staffell suggested. It's likely that for several years to come, coal could be useful as an on-demand energy source to help the National Grid deal with peak periods.

"You can turn [coal power stations] up when we need more, down when we need less – you can't do that with nuclear, you can't do that with renewables," said Staffell. Still, as renewable sources like wind power continue to rise in terms of electricity production in the UK, a largely coal-free future seems to be approaching.

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