While coal is thought to be the most abundant fossil fuel, it is still a finite resource. If current rates of consumption remain constant, it is estimated the world's known coal reserves may be exhausted by the 2140s.
The abundance of coal comes at a high carbon cost when we burn it to generate electricity. The UK Government has decided therefore that all new coal-fired power stations must incorporate Carbon Capture and Storage (CCS) technology to reduce their carbon emissions.
If CCS technology can be proved to be viable, this would remove the greatest constraint on using coal to generate electricity. However it it is currently expensive, and the lack of experience with the technology can mean insurance is expensive. There is only one operating coal-fired power station fitted with CCS (Oklahoma, US) which has been operational since the end of 2014. There are several development projects around the world (including 3 projects in the UK); however at the moment the technology is not economically viable without public support.
If costs can be reduced, CCS may enable coal to remain an important part of the UK energy mix, as a flexible and abundant energy source.