American coal-fired power plants were shut down at the second-fastest pace in history last year, despite Donald Trump’s frequent pledges to help the floundering industry out.

That’s according to a study by Reuters analysing statistics from the US Energy Information Administration, which found that power companies had converted or retired around 15,100 megawatts (MW) of coal-fired electricity generation in 2019, a drop that represents enough power for around 15 million homes.

It is the largest drop on record behind the 19,300 MW that was shut down in 2015, during Barack Obama’s presidency.

The decline marks a trend that has been seen for the past decade, as the energy source has been challenged by the production of cheap and cleaner natural gas.

Meanwhile, subsidised solar and wind energy have also cut into the market share of coal, which is a leading contributor of greenhouse gasses and global warming.

Is this the world's most beautiful coal mine? Show all 9 1 /9 Is this the world's most beautiful coal mine? Is this the world's most beautiful coal mine? The former industrial zone is now a green lung near Dusseldorf Jochen Tack/Stiftung Zollverein Is this the world's most beautiful coal mine? Nature has begun to reclaim the land around it Jochen Tack Is this the world's most beautiful coal mine? The land around the mine is now a kind of park Stiftung Zollverein/GNTO Is this the world's most beautiful coal mine? There's a sparse beauty to the mine Stiftung Zollverein/GNTO Is this the world's most beautiful coal mine? Zollverein's main shaft has become the symbol of the area Stiftung Zollverein/GNTO Is this the world's most beautiful coal mine? The exhibition is well laid out inside Stiftung Zollverein/GNTO Is this the world's most beautiful coal mine? The old pool in the mine Jochen Tack/Stiftung Zollverein Is this the world's most beautiful coal mine? Guided tours of a coal mine are more interesting than you'd think Jochen Tack/Stiftung Zollverein Is this the world's most beautiful coal mine? Zollverein's been transformed into an event space for locals Frank Vinken/Stiftung Zollverein

The trend has continued in spite of Mr Trump’s promises to bring “clean” coal back into vogue, and his denial that climate change poses the kind of generational threat that an overwhelming majority of scientists have said could devastate the planet over the next century.

Among those voters who Mr Trump has promised a resurgent coal industry are miners in West Virginia and Wyoming, which have been particularly hit by the surge in natural gas and renewable energies, as well as Obama-era environmental protections.

Despite his repeated promises both on the campaign trail and as president, an estimated 39,000 MW of coal-fired power plant capacity has been shuttered.

If that trend continues, more coal capacity will have been shut during Mr Trump’s first term in office (around 46,600 MW) than during Mr Obama’s second (43,100 MW).