there are some ways to do it. but they require technical knowhow and at least some offgrid infrastructure. the bitcoin economy as a whole is largely dependent on the nation state powergrid, and an internet connection. two vulnerabilities that quite a few bitcoiners dont like discussing.
the way i personally view it, is bitcoin is a legitimate system alternative that is still tethered to the system. meaning, its very good in a variety of economic and geopolitical upheaval scenarios. but i wont be relying on it as a means of exchange in a grid down scenario.