[KennyBlanken]

Emergency capacity is provided by natural gas turbine plants, which can go online in ~10 minutes, and respond to capacity demand in less time.

Coal takes hours and is not suitable for grid stabilization.

Grid stabilization in the UK is largely provided by hydro like https://en.wikipedia.org/wiki/Dinorwig_Power_Station

...which can go from 0 to 1.7GW in seconds. The UK has long used hydro to help with the "tea kettle" effect every time the BBC was between programs or went to commercial.

[toomuchtodo]

And where this is no hydro for grid services, batteries are taking over as they’re deployed (providing synthetic inertia vs that from spinning thermal generation).

[dralley]

Some former coal power plants (not sure if this is true in the UK, but it's true elsewhere) are being converted into flywheels for grid stabilization services. So real inertia is still an option even without thermal generation.

[toomuchtodo]

Any examples? I am interested in learning more!

[dralley]

https://www.siemens-energy.com/global/en/home/stories/irelan...

[toomuchtodo]

Ahh! Synchronous condensers, makes sense. I didn't make the connection when you said flywheel but should've. Thank you!

https://en.wikipedia.org/wiki/Synchronous_condenser

[Dylan16807]

> Coal takes hours and is not suitable for grid stabilization.

That's fine, because winter emergency capacity is not the same as grid stabilization. You need some amount of fast-reacting emergency power, but not all your emergency power needs to be fast-reacting. How to build the rest comes down to what's cheaper: extra peaker plants, or extra coal plants that are only used for a week every couple years.

[dmurray]

> the "tea kettle" effect every time the BBC was between programs or went to commercial

This effect is famous, although of course the BBC does not show commercial content in the UK. I wonder if the effect has diminished with the increased variety of entertainment. Coronation Street now peaks around 5 million viewers, down from 20 million in the 90s [0], and is on a channel that does show ads. Perhaps half time in England football games still creates a big power draw.

[0] https://coronationstreet.fandom.com/wiki/Viewing_Figures

[tialaramex]

It's known as TV Pickup.

Half time of a pivotal England World Cup game, shown only on commercial TV. I'm pretty sure finals (and maybe semi-finals) are always simulcast on the BBC so it's unlikely to have that commercial break element. There were a few big ones (>1GW) this century for big England games, and a notable one during COVID responses when people put a kettle on and then went outside to clap thank you to NHS workers.

But the other types of events, soap character's murderer revealed, long running drama ends, that sort of thing, are casualties of modern viewing habits - no longer a single identifiable (and potentially disastrous if not allowed for) bump.