The secret to these is still, IIRC, reaction time. For some circumstances, the expense per GWh of siphoned stockpiling is as yet practically identical to enormous battery exhibits like the Tesla cluster in (South?) Australia used to settle the network. In any case, the reaction time is requests of greatness longer. Really useful for foreseen changes in burden or putting away vitality for wind/sun oriented droops, yet at the same time needs blending with things like generators or battery clusters with speedy reaction times for the shorter transient practices on the lattice.
+2 1. charliehars commented 5 years ago on video Britain's Largest Battery Is Actually A Lake
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