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As for altitude as a variable, the boiling point may be a tad lower, but the amount of oxygen for the stove is lowered as well. There is probably a net loss as you gain altitude - just surmising.


I doubt that it would be as significant of a factor. With an open flame, fuel tends to burn just as fast at 5000 feet as at sea level. The amount of energy released is directly proportional to the amount of fuel burned so the rate of energy release is directly proportional to the burn rate.

There is an altitude where the air is so thin that alcohol won't burn, but there is also a point where the pressure is so low that water will boil spontaneously. Not sure which would be reached first.

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When the boiling point is reached is not subjective at all.


Actually, it is. The onset of boiling, referred to as nucleate boiling, is almost imperceptible to the naked eye. It takes a lot of heat to go from that point to the point where the bubbles are large enough to see. The subjective part comes in where the individual doing the testing decides that there are enough bubbles and they are large enough to call it a boil.

The best way to report the output of a heat device is in power conversion units (BTU per hour, Calories per second, watts, horsepower, etc.). It's relatively easy to do by measuring the weight of the water, starting temperature, ending temperature, and time.