The system survived the partitions, there was no widespread blackout.
Further, the system is not organized by the EU, but the ENTSO-E and contains e.g. countries from North Afrika.
According to the German Bundesnetzagentur (the equivalent of the FTC/EIA), the number of times where they have to intervene with the grid due to grid instability is constantly rising due to Germany shutting down nuclear and coal plants.
> https://www.bundesnetzagentur.de/DE/Sachgebiete/Elektrizitae...
It's perfectly possible to have a stable grid even with solar and wind.
The problem is that neither nuclear nor coal power stations are load following and "base load" has lowered over the years (industry has moved to Asia, devices became more efficient, etc.).
Stand-by power (like natural gas powered generators) hasn't been built up the way the way it should have been. Same goes for smart grid technologies and buffer storage; not to mention the maniacs (especially in South Germany) who basically protest everything - from nuclear power, to wind power, to required infrastructure like north-to-south high-voltage transmission lines.
It's way too oversimplified to reduce the issue to just wind and solar.
Where do you get that from? None of the sources reported a close blackout, as far as I understood it there was a lot of emergency capacity left. We weren't even in the emergency frequency range, as the other commenter pointed out.
Even the linked article just states that those interventions got more often after shutting down coal+nuclear, but it's not critical, it _only_ costs money to compensate the operators: https://de.wikipedia.org/wiki/Redispatch_(Stromnetz)
It's probably much less money than all the nuclear subsidies.
https://energy-charts.info/charts/installed_power/chart.htm?...
Nuclear power went from 20GW to 10GW. Hard coal went from 28GW to 22GW.
Ok, but gas went up from 23GW to 29GW. Brown coal stayed the same.
Renewables went up by by 50GW for PV and 50GW for wind. Consider that wind often hits a 50% capacity factor. That is 25GW in additional power just from wind alone.
Some of those plants may not be running continuously but they are still useful for emergency responses.