• ms.lane@lemmy.world
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    21 hours ago

    10 seconds of rotational momentum stored in turbines, such that if there is a skew in the balance of electrical supply:demand it will ‘sap’ that rotational momentum before the frequency starts starts dropping. Once that energy is depleted frequency will drop, in SA 1hz (from 50hz) is enough to trigger UFLS (‘Ultra fast load shedding’ - not fast enough for .6s momentum though) which will start dropping parts of the grid to try and keep at least part of it alive (restarting from a black system takes a lot longer than sequentially just adding de-energised parts back)

    ‘large spinny things’ - These don’t need to be big generators, they they can just be dyanmos (or better we start to move to a DC grid and just use capacitor banks.)