I think you misunderstood. I had electricity just fine during the storm due to the wonders of working infrastructure and thus not being in a blackout.
But, for those without power due to a blackout, you can’t simply spend money and instantly turn the lights back on. You can either have already spent money to have backup power, or you have a problem. It’s like breathing, if your drowning spending money to be able to breath in 2 hours is useless you need air now.
Which is why electric grid operators need infrastructure not money to avoid causing blackouts.
Perhaps an equally good "battery", this is the principal of fungibility as a currency. Given the built-in halving structure of bitcoin, in the long run bitcoin may "store" or buy more electricity relative to the dollar that has inflationary pressure (USD tends to lose 3%/yr in real value due to inflation).
Then Bitcoin stores no energy whatsoever. If I purchase the same amount of electricity with $, or with gold, or with seashells instead of Bitcoin, there will be no difference on the side of the electricity supplier. Aside from, of course, Bitcoin potentially affecting electricity prices.