What would it take to set it up so that a battery charges itself when the power is on, and then will provide power when the grid is down? I googled it, but didn’t seem to find anything helpfull to me.
Probably not too much. My grandparents lived out in the sticks and had no services. They used a gasoline-powered generator (5 hp Briggs & Stratton, as I recall; but they also had another one plus a Willys jeep engine attached to a generator) for their 120v power. They had a 12v battery attached to a charger, and the house had 12v lights in it as well as the 120v. Grandpa would fill the B&S with gas and turn it on around sundown, and turn on the 12v lights. The generator would power the 120v stuff, and when it would run out of gas the 12v lights would already be on.
You could do the same thing with the mains. Hook up a charger and a battery, run a few wires, and there’s your 12v lighting.
Me? I have flashlights and Coleman lanterns. If I need electricity I can fire up the Honda generator.
If you don’t want to provide too much power for too long, you can just simply use a UPS like you would use for your computer. Even if you want more, you can buy heftier versions of the same sort of appliance from those companies. Getting surge protection and so on is overkill if you’re just going to be running lights off it, but it would work.
Depends what you want. If you’re just looking for emergency lighting, search amazon for “emergency light.” They just plug into an outlet and come on automatically when the power goes out.
If you want full 120v power, a generator and automatic transfer switch will bring you to full functionality, but costs a lot. I’m sure it could be done with a battery bank and inverter, but I have no idea how to set up such a system.
Me: I’ve got an emergency light so that I’m not stumbling in the dark looking for a flashlight, and a portable generator with a manual transfer switch powering the essentials: fridge, well pump, a lighting circuit, and a few outlets. The power from cheap generators like mine is not clean enough to run TV’s or computers, as they’re made to run construction equipment.