For how long would it need to be mothballed before you’d be comfortable demolishing it? Important to be conservative wrt grid stability, but at some point, burn the ships so there is no going back.
Mothballed plants don’t really contribute to grid stability. They need to be kept in a pretty active state, ready to spin up at a moments notice in order to be any use.
The fuel (coal) left onsite is also an environmental liability and really needs to be gotten rid of by burning it, necessitating a carefully planned shutdown schedule.
Realistically, there is no going back: once the last coal-fired plant is closed (in September 2024), it will be gone for good.
Meh we're down to 1.1% of generation being coal in the last year; low enough to stop worrying about. Lets worry about how to get rid of the 33.5% of gas!
We've gone over a month without burning any coal, but then the Ukraine war happened and we were at risks of blackouts. That 1.1% is likely heavily concentrated as a much higher percentage on a relatively small days over winter and/or where wind levels were low.
We probably want to be sure if gas imports are heavily hit again or a major interconnector goes down we'll be fine before entirely demolishing it.
There was an issue with gas in the 2022/23 winter as the Russia-Ukraine war affected supplies and caused prices to skyrocket. More coal than usual was burnt because of this. But it's a moot point now: coal-fired plants have continued to close in line with UK government policy, and the last remaining one is scheduled to close in September.
I suppose gas and coal are sourced from different places and that may give some resilience to the system. They also serve very different functions in the grid. Coal is for baseline and gas is for peak.
Coal is very much used only for peak in the UK in recent years. The remaining plants (in fact, there’s only one still in service now) are kept on standby during winter and activated only when demand is forecast to exceed supply (plus a safety margin).
Gas is now more of a year-round flexible baseload, taking up the slack whenever demand is high and/or renewables production is low.
Nuclear is now the only true baseload in the UK - always generating more-or-less the same output except when they have to be shut down for maintenance, refuelling, or decommissioning!
These days, it's nearer the other way around in the UK - gas is closer to baseload (sort of) and coal has a profile closer to a peaker (especially when turning up/down rather than on/off).
