Why pay for coal?

Coal is the dirtiest fuel we have. Coal burning produces more pollution than other fuels and more than twice as much CO2 per killowatt-hour than gas,

So why does the UK government subsidise coal? A recent Overseas Development Institute (ODI) report shows that the UK provides subsidies of £356M per year to the UK coal sector. That's despite its stated commitment to phasing out coal-burning no later than 2025.

This makes no sense. It ought to stop.