I have been wondering about the differences in fuel consumption (by weight) between white gas and canister gas stoves, especially for winter use. So, I did a little testing on the stoves I have in hand. Since my typical usage for snow camping is to fire my stove up in the evening once and the morning once, running it continuously until I have melted enough snow and heated enough water for my needs (or for mine and my companion’s needs if not traveling solo), I wanted to test fuel consumption for a longer burn than just boiling a liter of water. So, I got out my largest pot, an aluminum 4 liter, and filled it with 12 cups of 50 degree water for each run. Air temperature was about 40 degrees. I would have liked to run this test at a colder air temperature but these were the conditions when I go the time free to do it, and anyway I don’t see temps much lower around here anyway. I weighed fuel containers before and after each run to get the weight of fuel consumed. I measured the temperature of the water and turned off the stove when it hit 200 degrees. I picked that temp because on my thermometer, there’s a clear marking there but not at 210 or 212, so it was easier to get a clear, consistent reading. I did not measure time, since it’s only fuel consumption that I’m interested in.
MSR Simmerlite – 43 grams
MSR Whisperlite – 43 grams
Coleman F1Ultralight – 34 grams
Bulin B5 – 42 grams
Note that the Bulin is the stove that is now notorious for its poor quality fuel line, so I wouldn’t use it in the field, I just tested it since I do have it. Interestingly, it ran poorly this time as compared to the only other time I have tried it out, and that time I ran it with the canister upright, this time inverted. It sort of sputtered to varying degrees for most of the time it was running. Perhaps I was getting some of the jet clogging that others have experienced with this stove.
The Coleman is not really suitable for winter use without employing tricks to keep the canister warm that I would rather not get into. But again, it’s what I had, and I figured I could extrapolate a little from its performance – to wit: BPL measured the coleman at 10.4 gms/liter boiled. It also measured the Primus Express Spider (the current remote canister stove of my dreams) at 11.7 gms/liter boiled. Assuming (boldly, I know) that the percentage difference would be the same for this type of usage, that would mean 12.5% percent more fuel usage for the Spider than the Coleman, so that in theory it would burn 38.25 gms if I ran the same test with it.
Now the fun begins. My average fuel usage with my Simmerlite for 2 people snow camping in Sierra Nevada springtime conditions has been a little over 86 gms/day of WG. That means for an 8-day trip, 690 gms, or 32.5 fluid ounces of WG. I use a pint Sigg bottle and then plastic bottles for the balance of the fuel. I’d need 2 plastic bottles at 42.5 gms each, plus the fuel bottle at 142 gms with the pump, plus the fuel weight, plus the stove at 266 gms (with windscreen& lighter, and in silnylon bag), for a total of 1183 gms.
Now the Spider – as extrapolated – would need 613 gms of fuel to do the same burn time. That would mean either 3, 220 gm canisters – a little more fuel than needed at 660 gm; or 1, 450 gm and one 220 gm canister – even more fuel, but lighter. So, going with the 450 & 220 combo, that’s a net weight of 880 gms fuel and containers, plus the stove, windscreen,lighter at 285 gms for a total of 1165 gms.
That’s at the start. At the end, the Simmerlite and empty bottles are 493 gms, while the Spider and empty cans are 495.
Well, shoot. That’s pretty darn close, both starting and finishing. Now, I realize this is partly guesswork, but I think the guesswork is reasonable. What’s more, since by dumb luck the fuel usage for my tests was almost exactly half of my average daily usage, and I do two burns per day, it seems like a fairly realistic simulation in terms of amortizing the priming of the WG stoves.
I should stress that this is only applicable if you do as I do, and only light your stove once at night and once in the morning, and don’t so much cook as heat water and rehydrate stuff. If you light your WG stove several times, for different courses or whatnot, this will change in favor of the canister, as you’d have more priming.
Also worth noting is the fact that I had earlier tested the Simmerlite vs. the Whisperlite for fuel efficiency when boiling 1 qt at a time, and the Whisperlite was slightly more efficient – about 8% better. So it looks like that may have been due to the Simmerlite using a little more fuel to prime, but it apparently catches up over a longer burn time.
Well, interesting. And this conforms to some other testing and calculation I have done other ways that suggest the two fuels are so close, for my style at least, that the choice should come down to other reasons than weight.