Here are some alternatives nobody else seems to suggest but work great for me.
At level 3 fabrication, with some basic tools and a welder, you can make a charcoal kiln. Fill it up with a little wood and light it up for a 3x3 pool of useful light. You can repeat the process every now and then for charcoal or don’t bother and enjoy the light source forever.
At level 5 electronics you might be able to build an inactive turret. Activate this for a 11x11 pool of light (only 7x7 is sufficiently bright to read with no penalty). You don’t need to provide it with any ammo if you only want to use it as a lamp.
At even higher levels of electronics, blessed with a rare book and a rarer drop, you can create control laptops which can reprogram hostile turrets. Once a turret is friendly you can walk into it and deactivate it, granting you another inactive turret and its cache of ammo. Robbing a lab or military bunker will provide you with enough light sources to light all your rooms and much of the street outside.