If you're thirsty, one pitcher of ice water is way better than none. But two pitchers probably won't make you twice as happy, and indeed each additional pitcher will be less and less appreciated.
The same thing is true with electrical outlets. We probably don't need every outlet in our home to work, but being able to run one or 2 things at a time is far far better than allowing everything with a cord to become a useless paperweight.
Unlike water, sewer, gas, or the internet, the electrical grid is centralized and electricity is difficult to store in large volume locally. Until recently, it was also hard to generate locally. Luckily, we live in the future now, and things have changed.
Below are what I would consider the 3 best options for quickly and easily solving this problem. They are all highly rated and eligible for free shipping too. You don't need all 3, although personally I have something similar to each of them as well as other redundant backups of all sorts. (Note: affiliate links below, I will donate any theoretical proceeds to the Red Cross).
On the storage side, a simple portable power supply can allow you to charge your phone or other small devices:
A portable jump starter can do everything that the portable power supply does, but can also jump start a dead battery, inflate your tires or air mattresses, and has an adjustable light.
Generation has never been easier either. New small, quiet, light, and low emissions generators are easier to store and move, run on much less fuel, are much quieter than cheap "contractor" generators, and are even CARB certified (California's air quality standard is the toughest in the U.S.) so they pollute less and are safer. You still have to run them outside, but they can be kept closer than a poorly designed cheap generator.
Amazon has an informative buying guide on generators, but if I didn't have one already I would buy this in a heartbeat. Sure it's almost 1000 dollars, but how much would you pay to be able to stay in your house after a disaster? Buy the best and cry once.
This thing won't run your central AC or large heating elements, but it will run things like your fridge, tv, lights and fans, phone chargers etc.,
Solar and other alternative sources are great as well, but beyond the scope of this posting. Still, there are lots of new and surprising things out there, from portable stoves and water heaters, to decent freeze dried food and hand crank lights and radios. This helpful recent guide I stumbled across the other day has a quite few things that I already own and a few things I would like to get.
And finally run through a drill and use this stuff to make sure you are happy with the results ahead of time, so you can be sure you are covered when shit goes down!