Re: it can only take the output of about 15 Dogger Bank turbines
"Looks like you'll need about another 200+"
If I read this correctly, you're saying we need to build 200 more of these here to store the output of 'Dogger Bank' as a whole.
We appear to be talking about 196MW of storage per multi-unit site...so say 200MW, for a few percent of the peak load period Each 200MW site appears to be able to store and supply (later!) circa 92-94-% of one fifth of the older '1GWe' 'power stations' or one fifteenth of a modern (i.e. nuclear fission) UK electricity generation facility at about 3GWe.
One can't store something unless it is generated in the first place. The last thing we need at the moment is a large increase in load (1000s of electric vehicles @ e.g 15KW/h) combined with more bias towards electricity as natural gas becomes rarer/more expensive*) at the same time we're loosing generation capacity.
So call me back when there is something to replace the short, medium and long term loss in generation capacity we face due to eliminating fossil fuels and decommissioning the 'nuclear fleet', combined with the increasing loads involved with everyone plugging in their EVs etc...
* I have two elderly relatives who are already switching to electric fan-assisted convection heaters or plain old 'fan heaters' used in one room only to avoid heating the rest of the house. I know of at least one family-of-four who use a 10KW electric shower in an attempt to keep the gas bill down (Without doing anything about the overall energy bill - talk about 'Borrowing from Peter to pay Paul'!).
Mine's the one with the extra-heavy-duty thermal insulation.
Biting the hand that feeds IT
