I maybe wrong but what I think is Blockchain ledger exists as long as there are active nodes in the network. So can a blockchain can be shutdown by shutting down power supply across the globe? What would happen in such a case?
I think the transactions that were not added to the ledger would definitely be lost and they would have to be reinitiated. I think power shutdown would create inconsistency between different instances of the ledger at different nodes and even if the power is back we wouldn't be able to pick a safe state of the ledger.
What are the possible ways to shutdown a blockchain without having to go to each and every node and taking it down?