Solar changes the who and where, but really not the what significantly. Solar is far more distributed and less concentrated, and options for distribution are potentially more diverse (cables, direct power beaming, synfuel production and distribution) in ways that an oil-based economy hasn't been.
Even within national borders, power production and distribution are sufficiently centralised and choke-pointed that they are vulnerable to significant disruption, even by non-targeted accidents and natural disasters. Major national and regional power outages are not especially frequent, but neither are they unfamiliar: <https://en.wikipedia.org/wiki/List_of_major_power_outages>.
During periods of conflict, national and irregular forces routinely target power infrastructure, with significant but rarely absolutely crippling effect. For the past three-and-some years, two major eastern-European adversaries have been directly targeting one anothers' energy infrastructure. Though the results are costly, neither has been bombed back to the stone age, or even the pre-electrical era:
"Resilience Under Fire: How Ukraine’s Energy Sector is Adapting – and What It Means for Europe"
<https://rasmussenglobal.com/wp-content/uploads/2025/06/REPOR...> (PDF)
For the past 100+ years, the US has been spending a significant amount of money on protecting oil supplies to protect its oil billionaires and its economy. It's the #1 budget item, outspending the combined military spending of the next 10 economies. This can be reduced to zero, and ultimately, the $ 39 trillion deficit can be eliminated.
The EU is actually extremely special because its souvereign member states collaborate in almost all areas on a level that is unmatched anywhere else. But the ideological foundation is getting eroded by propaganda and if that assault is effective, Europe will balcanize again and end up experiencing many more armed conflicts.
Most in depth analysis I’ve seen of these Russia - Ukraine conflicts cite this as one of the top factors in why Russia invaded both a decade ago and the most recent war that is ongoing.
That is to say - mutual cooperation agreements like that have enough teeth to keep conflicts to a minimum as the repercussions are severe
Also another ultimate irony is that Russia didn’t completely cut the rest of Europe off from its oil and gas. That symbiosis continues albeit not the same way. Perhaps electricity would be the same