Following up on our discussion in January about a propane burner for hot-water dyeing outdoors and possible alternatives, I've just acquired an electric portable induction burner. It's 1800 watts, the highest I could find, for fast heating.
I tested it outside with one gallon of water in it, on the highest temperature. I started with tap water at 81°F (that's 27°C). After eight minutes, the temperature reached 140°F (60°C); after five minutes more, it was at a high simmer, 201°F; and after a total of eighteen minutes it was at a full boil, 212°F (100°C). This was all with the lid on the pot. That's pretty quick!
It's easier to set up than a propane burner. All I had to do was plug it in and turn it on. I happen to have a stone bench that's big enough to give the required four inches of space between the burner and the wall (which is made of non flammable concrete siding). The outlet is right next to the bench, by a happy coincidence. I'm all set to go. No more problems with dyeing polyester with stinky and possibly hazardous dye carrier/color intensifier chemical, something I did inside my house exactly once and swore never to do again.
Since it's an induction stove, it works only with pots that a magnet will stick to. Fine for me since my 33-quart enamel dyeing pot and my 12-quart stainless steel dyeing pot are both magnetic. Not so great if my husband wants to borrow it for brewing beer, since our stainless steel beer brewing pot does not attract a magnet. We could put an iron heat diffuser on to use it with the brewpot, though.