Generation at the 2 GW West Burton A coal plant in Nottinghamshire will cease by Sept. 30 2022, the generator said March 22 in a statement.
Over the next 18 months two of the plant's four 500 MW units would be available "purely to meet capacity market commitments, in order to assist with security of supply," EDF Energy said.
"With EDF's power generation strategy firmly focused on nuclear and renewables - and in this key year for UK leadership on climate change - we now believe it is the right time to provide clarity to our employees and all those connected to the site," said EDF's Managing Director for Generation, Matt Sykes.
As Drax's last two coal generation units are also set for formal closure end-September 2022, the UK would then have just one coal plant left, Uniper's 2 GW Ratcliffe-on-Soar.
Until recently West Burton A had been listed in National Grid data as closing in September 2021.
The plant did not win any agreements in the March 2 one-year-ahead capacity market auction for 2021/2022 delivery, but there is a secondary market for the agreements and internal company transfers from one asset to another are possible, said Glenn Rickson, S&P Global Platts Analytics' manager, European Power.
As such, the decision to keep the plant online for an extra year "could reflect the perceived increase in value for flexible plant in light of the extreme price spikes seen this winter, offering the potential for relatively inefficient plants to recoup their annual operating costs over a handful of very expensive hours," he said.
EDF Energy was not immediately available to comment on these options.
Recent system tightness saw one of Drax's coal units called by National Grid in the Balancing Mechanism for GBP4,000/MWh, underlining the potential for UK coal to make money despite reduced running hours.
On March 5, Drax confirmed it had ceased commercial coal operation at its Selby site in Yorkshire, but its last two coal units, amounting to 1.3 GW, remain available under capacity market agreements.
West Burton A began generation in 1966.
