The Times this morning had a quote from "energy bosses" that a "very strong oscillation in the electrical network" led to disconnection from "the European system" - i.e. France. I have not heard that anywhere else, so either the Times is very good at digging out sources, or it's wrong. Since it's what such bosses would have said if asked in advance what was the most likely cause of a hypothetical transmission grid collapse, perhaps it was basically a guess - by someone.
At a more recent press conference, the start of the collapse was said to be the disconnection of five (I think) nuclear generators, supplying more than half of of the demand at the time. Now, something must have caused that, and oscillation (instability) fits that bill. After that, total collapse was almost inevitable - it could only be avoided if the links from France (and Morocco, much smaller) could supply most of that deficit (15 GW» ), which sounds pretty unlikely.
Those links from outside all overloaded and tripped, though for the south-west of France the split was within France. They had to break the connection at the Pyrenees before resupplying from the French aside. The powering up of Iberia was done starting from the areas that could be supplied from abroad, in he north and south.
That sounds like the process I would expect to see. Starting the generators in a grid involves them following a grid already supplying power, so that was done using the external links. As much of the grid as could be supplied by those infeeds, at the north and south, was turned on and the generators in that area started up. That gives enough surplus power to prime the next areas and get them going.
There is some concern with Grid systems that rely heavily on renewable generation of the lack of inertia that spinning mass generation provides. In the event of a fault on the transition system the Voltage takes longer to stabilise with renewables based generation, Power Factor is also something more challenging the manage.
Black starting power stations ie a power station that has no live Grid takes time even natural gas fuelled.
It will be interesting to see the finding of the instigation[
quote author=broadgage link=topic=30210.msg361041#msg361041 date=1745947316]
I have long held the view that ALL new electric trains should be equipped with either a diesel engine or a battery able to move the train at a much reduced performance for a reasonable distance.
In stating this, I was thinking primarily of
UK▸ conditions, but it looks as though it would be prudent overseas also.
At least affected passengers were allowed off the trains, in contrast to the UK policy of "keep them on the trains no matter what."
On a more general note, there appears to have been a regrettable lack of both battery emergency lighting and standby generation in public buildings.
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In the case of UK electrified railways the loss of traction power results in the loss of power to signalling, normally not a problem as there are independent locally sourced
DNO▸ supplies; however should an Iberian Peninsular type of failure occur there would be no DNO available. And no putting generators everywhere of UPS's large enough to run for hours is not economically practical ................... quite simply the travelling public are not willing to cover the cost for what is an extremely rare event