We are beginning to recover power in the north and south of the peninsula, which is key to gradually addressing the electricity supply. This process involves the gradual energization of the transmission grid as the generating units are connected.
I see load dropping to zero on that graph, or rather, load data disappears an hour ago.
If the grid frequency goes too far out of range then power stations trip automatically, it's not an explicit decision anyone takes and it doesn't balance load, quite the opposite. A station tripping makes the problem worse as the frequency drops even further as the load gets shared between the remaining stations, which is why grids experience cascading failure. The disconnection into islands is a defense mechanism designed to stop equipment being too badly damaged and to isolate the outage.
Interesting, but in terms of load I think think the data may just be delayed by ~1 hour. Switching to UTC, to avoid timezone confusion, it's currently 13:10:
Everything dropped to zero except wind and solar, which took huge hits but not to zero. I expect those have been disconnected too, as they cannot transmit to the grid without enough thermal plant capacity being online, but if the measurement at some plants of how much they're generating doesn't take into account whether or not they were disconnected upstream they may still be reporting themselves as generating. You can't easily turn off a solar plant after all, just unplug it.
Either that, or they're measuring generation and load that's not on the grid at all.
Probably they are estimates of not grid metered generation assets based on wind speed and solar production, at least in the UK nearly all solar is 'estimated' because it is not measured directly (apart from larger sites), at least in real time.
Rooftop solar for example just shows as a reduction in demand, not 'generation' per se.
This also true for private wind power. Britain has a measurable amount of hill top farms where it just makes good economic sense to install a wind turbine and get free electricity. But we don't meter it, it shows up in charts as an absence - on a windy afternoon maybe Britain is seemingly consuming 4GW less electricity than it "should be". If the wind drops that load reappears on the grid and must be handled by existing infrastructure.
None of this gear is suited to a black start. If you had total grid loss for a month you could doubtless rewire it to power the farm when it's windy despite no grid, maybe even run some battery storage for must-have services like a few lights so they keep working on still days but you could not start the grid from here.
Would this suggest the grid hasn't snapped apart, or is it just not possible to tell from the data?
Coal, pumped hydro, and nuclear generation all went to 0 around the same time, but presumably that's those sources being disconnected from the grid to balance demand? https://transparency.entsoe.eu/generation/r2/actualGeneratio...