Hmmm, for indoors during a power outage I go away from anything I'd take for a walk. A single burner butane stove like the Amazon butane stoves are fairly cheap and they work really well.

The basic design seems to be universal, I s'pose the patent ran out or was simply overrun. I have a stainless model from Gas One that simmers well and boils water faster than my stovetop. Iwatani markets a couple that are very nice at over twice the price and also available from Amazon. IME they burn clean, crack the window and don't worry about CO.

I wouldn't consider the other fuels: kerosene, white gas, et al -- for use inside. I never tried Esbit or alcohol because those stoves aren't in the same class for serious cooking.