EDF Energy is to close a coal-fired power station because of “challenging market conditions” and the drive to decarbonise electricity generation.

The company said it was proposing to cease generation at its Cottam coal-fired power station in north Nottinghamshire on September 30.

A statement said the site has played a critical role in keeping the lights on for more than 50 years.

The Prospect union said the closure was “premature”, describing it as a “huge blow” to workers and the local economy.

Cottam plant manager Andy Powell said: “When the power station was built it was designed to operate for 30 years. It’s a credit to our people, the engineering and EDF Energy’s investment that it has operated for more than 50 years.

“There has been an aspiration to move away from coal for a long time now and we have prepared thoroughly for the closure.

“We have a highly skilled and experienced workforce and we’re determined to support our people throughout this process.

“We are conscious of the need to support a just transition to a low-carbon energy system. Our ambition is to close the station safely and responsibly by managing people and the environment properly and continuing to be a good neighbour.”

EDF said it would honour commitments under the Government’s capacity mechanism to pay for back-up power to continue operating another coal-fired power station at nearby West Burton until the end of September 2021. It will review the future of that station beyond that date.

Prospect said 300 jobs will be lost as a result of the closure.

Mike MacDonald, the union’s negotiations officer, said: “The premature closure of Cottam power station will be a huge blow to workers and to the economies of Worksop and Retford.

“We had been led to believe the power station would be wound down by 2025, which would have given plenty of time to mitigate the £60 million which will be lost from the local economy as a result.

“That lead time is now gone and we need reassurances from the company and from the Government that they will do all they can to minimise the impact of this closure.

“Prospect has been working hard with employers, including EDF, to secure a just transition to low-carbon generation ever since the Government indicated that it would wind down coal-fired generation by 2025.”

Coal has been making up a shrinking share of electricity generation in the UK, ahead of the Government’s deadline to phase it out by October 2025.

In October, the Business Department said the UK was on track to get less than 5% of its electricity from coal for the first time since the Industrial Revolution, and to take polluting coal power off the grid ahead of the 2025 deadline.

On the international stage, the UK and Canada have launched a coalition to encourage countries and states to move past coal power, called Powering Past Coal.