I keep a small solar/crank generator/USB-powered radio in my car. Which can provide USB power, act as a light, and also, in a pinch, charge my cellphone. You can get these starting at about $13 on Amazon.
That's not quite as good as having one with everyone, but as long as you're within walking distance of your car, you can probably get to it. It also has some benefits:
More power-friendly than a cell phone.
At least a portion of the kinds of things that might take out the cell infrastructure (e.g. cyberwarfare targeting the cell system) may also take out phones themselves, like if someone can push bad updates out to the phones. Your dead-simple FM radio isn't going to have problems unless actual FM radio broadcasters get knocked out.
If you're in the US, there is very little real opportunity for someone to conduct a significant, conventional attack on the country, but being able to find holes in the Internet-connected infrastructure and do damage there has a lot more unknowns and the ability of various parties to disable or destroy it is much more of a possibility. Militaries do build up collections of holes to hit adversaries with. One of the first things Russia did when invading Ukraine was to knock out Viasat infrastructure, using a hole that they'd discovered in that company's network, to degrade communications in Ukraine by pushing out an update to brick satellite modems. I also remember some guy at a think tank in the US that covers cyberwarfare saying that one of the surprises was that Russia didn't try to disable Ukraine's cell network, either via cyberwarfare or via conventional means; taking out the cell network would do a lot to dick up a country.
I saw a YouTube video where someone was testing crank powered phone chargers and they weren't able to get enough juice to ever power the phones. Have you tested it for that purpose?
It charges a battery in the radio, and then that discharges while charging other devices. Now, you may be spending an unpleasantly-long amount of time cranking the thing, but that's another matter.
I haven't used it to charge the phone. I normally carry a number of other devices that provide charge, including a larger set of folding solar panels and another battery bank, in the car, and I've used that, but not this particular solar/crank charger.
When you see how little energy a Tour d'France cyclist can generate, with their legs, over a given period of time, it becomes clear why these crank things are useless.
You could possibly charge a phone with a cycling setup, I haven't done the math in a while. What I recall is the human body makes for a terrible generator.
Humans are efficient, and there are also huge losses in converting the energy from work to electricity, and then further converting this to whatever voltage you actually need, while also likely first charging a battery somewhere so you can use it at a different time than you are cranking/pedaling...
However humans are also strong and can think of mechanisms that help with leverage and whatnot; for example an elliptical machine would probably be better than a bike.
With that being said the power you can generate is still pretty small; around 100Wh is floating around. If you worked out more you'd make more, obviously, but that might not be feasible.
It'd still be more than enough for essentials like charging your phone though.
Fair enough. I'm not too worried about it charging (though I am confident that it will be an enormous amount of work and possibly take multiple passes while leaving the cell phone off). For me, this was more a "throw one more backup layer" on things; when I'm in the car and carrying what I normally lug around, I typically have:
The ~100Wh car battery and USB adapter off the cigarette lighter.
A tank of fuel to charge said battery.
A car jump starter (in case said battery goes dead), with its own battery that can do USB.
A laptop with its own battery with USB output.
A tablet with its own battery with USB output
A small power station.
A second, 100Wh power station.
A ~400Wh large power station.
An unfolding set of solar panels with another small power station.
The aforementioned solar/crank charger with a very small power station.
Having to actually crank anything is going to be about at the bottom of the list in terms of things that I'm going to be doing in any situation, so this is about 9 things that would have to fail subsequent to my cell phone battery dying in a situation where there's an emergency for this to come up.
I did consider a more-serious charger at one point, but that would have been a pedal power station; it's vastly easier to generate a given amount of electricity with your legs than your arms. If having it in the car or house is all you need, that's probably a better choice if you're worried about it (and you can definitely find video on YouTube of people charging phones with it):
There's also someone that sells a tiny thermoelectric camping generator that can run on wood. If you're really concerned about needing power, my guess is that it's probably less-work to find something you can burn in that.
EDIT: I also have an AA-battery-to-USB-and-USB-to-AA-battery powerstation somewhere, but I don't know if that's actually in the car. I think that that's at the house.
Arent you supposed to crank charge a battery for a while, and then charge the phone or other device via the battery? Or do you mean they couldnt meaningfully charge the battery at all
I got one after the crazy storms we had over the summer. Had an old cube Nola radio that ran on a 9volt we had growing up but that has long since been lost
I also remember some guy at a think tank in the US that covers cyberwarfare saying that one of the surprises was that Russia didn’t try to disable Ukraine’s cell network, either via cyberwarfare or via conventional means; taking out the cell network would do a lot to dick up a country.
Russia didn't disable the cell network because they were using cell phones to coordinate their forces (as presumably they didn't have proper radios).