in case of global powerotage btc would be the last to think of. I would be more concerned with the hundreds of nuclear plants melting down because the cooling would stop. Global power outage is an extinction-event. Btc is not relevant in that scenario.
I hate nuke plants but on most the backup generators should kick on
Wish it were so but not sure it is. Backup generators (if they were not fried by a EMP/solar flare) can sustain for awhile but they need a lot of fuel. All fuel runs from and to the refineries by the grid power. One would hope the powers that be would find a way to keep them all running indefinitely but it is a leap of faith, there are a lot of them.
I live near the largest one in the US, just outside of Phoenix. Not much water so they run the city's sewage through the reactors to cool. Clever (and kind of the nastiest place on earth if you add it all up) but I can't help but think if the grid was down for a long time there is no way they could run the whole plant and the sewage pumping and everything attached to that without a weak link somewhere.
Hope we never have to find out. We are very much dependent on the grid, but elsewhere I saw a thread that they are launching cubesats for bitcoin transactions so that is a good start on redundancy.
