Lightweight Stove Systems for Group Cooking Part 1: Basic Framework for Selecting A Cooking Pot and Predicting Fuel Needs

[Ryan Jordan]

Companion forum thread to:

Lightweight Stove Systems for Group Cooking Part 1: Basic Framework for Selecting A Cooking Pot and Predicting Fuel Needs

[Roger Caffin]

Hi Gary

> I'd love to have one of you physics types to tell us about partial pressures and how
> fast each type of gas gets used up.
Been there, done that, you must have missed that article. :-) Try
http://www.backpackinglight.com/cgi-bin/backpackinglight/effect_of_cold_on_gas_canisters.html
for all the info you need.

Cheers
PS: some of the graphs in that article seem to have gone viral around the web.

[Stuart R]

Gary, to learn about partial pressures, read the Cold Canisters article

In short, 25% propane is good to start with but performance quickly drops off.
For more consistent performance with an upright stove, look for a canister with a high % ISO-propane, like Jetboil or MSR Iso-pro.

But to be honest, any upright stove is going to struggle at sub-zero F, you need to look at an inverted canister stove at these temperatures.

[Bob Gross]

"Hey, you hiking this week?"

I was hiking just yesterday. The temperature on my patio this morning was -1 C. I'll let you ponder that number in your heart. That was almost as cold as it ever gets around here.

–B.G.–

[Gary Dunckel]

Jerry, the fuel consumption of each test only varied by a single gram, so each boil was essentially the same. But this was for only 2 tests of each flame level–hardly scientific, but functional (in the interest of saving some fuel).

Roger and Stuart, thanks for that link. I somehow missed the article when it was published here. I'll read it now.

Tomorrow morning I'll try the higher temperature hand warmers (and I'll closely monitor the heat output, Roger, I assure you).

Edit–I guess that I did read that article before. I remember that I found it a bit hard to follow (physics wasn't my strong suit when I did my pre-med), and I got tired of converting temps from C to F while reading it. So I took the general concepts, and let it go. Definitely a good article though.

[Ethan A.]

How do these inverted remote stoves compare for heat output and CO?

[SAM LAMBERT]

I did my own patio test with a small alcohol stove (Trangia) one cold morning at zero F (32 degrees F below freezing or -18 Celsius). The cup of water, the alcohol fuel and stove had been kept indoors at about 65 degrees F before I lit the stove in the snow (they could have been kept inside the sleeping bag with me all night if I had been camping). No wind, no windscreen. I did not record the time it took to boil the water, but it did not take too long.

The point is alcohol is not completely useless in severe cold — it heats a small amount of water OK for UL type cooking, perhaps as useful as it would be in warmer weather. I did not try melting snow.

I would try some more thorough testing and careful recording of results if I still lived in a cold winter climate. Maybe someone else who does live there could do it.

[Bob Moulder]

Hi, folks!

I am new to the forum and this is my first post. However, for about the past 25 years I have participated in and led quite a few multi-day winter trips in the Adirondacks, Whites, Catskills and Katahdin in temperatures of -10 to -33degF. Our rule of thumb that worked uncannily well all the time with XGKs and Whisperlites was 1 pint of fuel (Naphtha… Coleman 'white gas') per person per day. This sufficed for cooking and snow melting, and if running water could be located we would sometimes end up with a little fuel surplus.

Bob Moulder

[Roger Caffin]

> 1 pint of fuel (Naphtha… Coleman 'white gas') per person per day.
Ahhh … let's see.
1 pint is approximately 0.5 L. White gas density is ~0.78 g/cc.
So that's roughly 390 g per person per day.
Oh My God!

Typically I would budget ~60 g of canister fuel per day for the TWO of us, and typically I would double that for kero or white gas, to 120 g/day for TWO. That's 60 g per person per day for white gas. If I could find running water a lot of that came home. (Summer use was about half of the above.)

Welcome to BPL. I hope we can get your pack weight down a few kilos!

Cheers

[Jeff McWilliams]

I recently read over the ADK Winter Mountaineering School student handbook and noted this same fuel recommendation that Charles mentions. I assume, Charles. that some of the trips you led are WMS trips?

I was mountaineering with a group on Mt Olympus and Mt Rainier two years ago. The group leader insisted on an inefficient group cooking system, and making group meals that required simmering for 5-8 minutes. Dinner meal ingredients included stuff like cheese tortellini. Picture a huge aluminum pot containing food for 10 people. Three MSR Dragonfly stoves were running simultaneously under the pot, and they all had to be tended in case one ran low on fuel or air pressure.

Breakfasts were instant oatmeal type stuff. Lunches were usually no-cook foods that were easily consumed while walking or during short breaks.

We still didn't consume 0.5L per person / per day, and we were also melting glacier snow for water. For four days on Rainier, that would have been 20 liters of fuel!

The WMS handbook specifies freezer-bag-cooking type meals only, so I can't fathom why so much fuel is being used per day.

Does the ADK/AMC WMS use heat exchanger pots?

Both the AMC Mountain Leadership School and ADK/AMC Winter Mountaineering School appear to be very traditional, heavy pack type classes.

[Gary Dunckel]

I'm not sure if this is the right place to post this, but I suppose it will do. I contacted JetBoil CS to ask about the exact proportions of the gasses in their fuel canisters, and this was her reply:

24.87% Propane
71.97% Iso-butane
3.16% Butane

Wow–this is some serious canister fuel for winter usage! I couldn't find this information anywhere on the web, so it was great of JetBoil's CS to provide it to me.

The drawback to JB fuel is that their small canisters contain just 100 gm. of fuel, as opposed to the 110 gm. that most other brands do. But the gross weight of a full canister is lower, around 6.85 oz.

Does anyone have an empty JB 100 gm. canister that he/she could weigh (include the protective cap, please). I'm curious as to whether the JB canister has been beefed up like the MSR and Optimus ones. I have assumed that it is necessary due to the increased internal pressure from having a greater % of propane inside. But maybe this isn't true, and that MSR and Optimus are over-engineering their canisters (thereby adding unnecessary weight).

[Kevin Buggie]

Page 26 of the ADK WMS handbook states to bring 10 oz. fuel per day if water from streams is available, and to consult trip leader on additional fuel required for melting snow.

Like Roger said, YIKES!

My Optimus Vega canister stove, inverted, might weigh twice the Caffin Evolution stove but is still a BPL dream snow-melter compared to white-gas stoves of my past.

[Roger Caffin]

> I contacted JetBoil CS to ask about the exact proportions of the gasses in their fuel
> canisters, and this was her reply:
> 24.87% Propane
> 71.97% Iso-butane
> 3.16% Butane

What she did not tell you about was the 5% dirt.

To explain: I have seen and tested these generic canisters. They come from China and have been branded in several ways. Yes, they cost less than the 'western' ones – even if the retail price is no different. The contents is unfiltered raw gas: dust and all. The dust blocks up a winter stove very smartly. Been there, suffered that.

Reality check: do you REALLY believe the Chinese control the propane content of the gas to that accuracy???? Two decimal places???? I will stick my neck out and say they could not even manage 1%. I doubt they even KNOW what the composition is today. Most Western companies will quote something like 70%, and hope to be within 5%.

In the case of the Chinese canisters, I suspect that they did ONE lab measurement at ONE time and got those figures by calculation, with absolutely NO regard for the accuracy of their measurements, and have blithely been quoting them ever since. Very clearly they have absolutely NO idea of measurement accuracy – or scientific integrity. Very Chinese.

If Jetboil are now buying cheap gas canisters from China and happily claiming those specs, then very clearly Jetboil has gone down the tube (technically speaking) and has NO idea of what they are talking about. Should you buy canisters from them under those conditions? I leave deciding that question to you. Just do not (ever) invert the canister!

Cheers

[Gary Dunckel]

Roger, I'm so glad that you responded to my comment. I'm trying to figure out the best performing canister mixture that works for various ambient temperatures. For temps at/above, say +32*F (0*C), at 8000-10,000' evevation, do you think that a pure iso-butane content would be optimal? I mean, why bother with either propane or the lowly butane in those conditions? If so, why hasn't anyone marketed one?

And finally,

What brand of canister fuel do you respect the most, considering most mild conditions and moderate altitude?

[Roger Caffin]

Hi Gary

Well, I returned the two Chinese 'Primus' canisters I had bought and got a full refund. I don't remember what I said in the shop (no, I did not shout), but they seemed happy to refund me and get me out of the shop!

My favourite canister for summer use – not fussed as long as it works. I use Kovea canisters a lot, and they (so far) seem honest. The MSR iso-butane ones should be pretty good too, ditto the Coleman ones if you can get the 30% propane version. Don't buy any 100% butane canisters unless you are desert walking in the summer.

For winter use I love the Powermax ones. Seriously. The French Campingaz ones also seem very reliable, along with the ones mentioned above if used inverted. But I have gone off the Primus brand after that incident, and I would not touch the Jetboil ones now either.

How to judge? If the gas composition is something like 30% propane / 70% butane, fine. If the canister quotes the gas composition to one or two decimal places it is likely Chinese, and forget it!

My 2c.
Cheers

[Kevin Buggie]

@roger. Do you know by fact that Jet boil is using unfiltered gas? Or are you kinda ranting and conflating brands (Chinese primus)?

If the former, that would be significant for many users with the big JB designed for remote inverted use. Doesn't seem plausible. My JB canisters purchased in north America are labeled ' made in Korea', and never clogged my Vega, though I've only burned 5 canisters (inverted) worth of fuel in it this season.

Is there a different production model of JB canister you're referring too? Or only relevant to eastern hemisphere purchases?

Please clarify

[Gary Dunckel]

Thanks for your response, Roger. I always appreciate your learned insights. I happened to buy a JetBoil canister yesterday to try out. On the can, it says "Made in Korea." It happens that the JetBoil, MSR and Optimus canisters all are made in Korea, and they all have identical protective caps (maybe different colors). Hmmm…maybe all made by Kovea? Snow Peak doesn't mention where their's are made, maybe Japan? Their protective caps are different, and are stamped with "Snow Peak." My 10-year old CampingGaz and Primus Power Gas canisters were both "Made in France," so they're probably OK. All of my 4 ounce canisters appear nearly identical dimensionally, with the only apparent difference being the color of the metal as viewed from the bottom of the canisters–Optimus and JetBoil are a light gold color, the Snow Peak a bit darker gold, and the MSR is silver. Do you suppose that this is due to some sort of brass/steel composition differences?

I'm certain that I am over-thinking all of this, Roger. But that's what some geeks do to help pass the dark, cold days of winter. I'm just trying to study the canister weight/number of boils/ambient temperature performance of these various fuels. Maybe I should move on to dehydrating/vacuum sealing next summer's food supply instead?

Thanks again, Roger.

[Jerry Adams]

I've used a couple Jetboil canisters. 8.1 oz/230 g. Upright. Worked okay.

I don't think it matters which canister you use if you're upright. They're all mostly isobutane. Get cheapest or whatever's available. Just based on my experience in U.S. at REI – Jetboil, MSR, Snow Peak.

The Burton canisters from Fred Meyers are $2.50 or $3 for 8 ounces which are cheaper. Made in Korea. Same lid as Jetboil except different color. Same size as Jetboil.

The Snow Peak that I bought a couple years ago is from Japan, slightly different weight, different cap,…

If isobutane, upright works fine above 25 F or 30 F.

If you find a butane canister then maybe 40 F (based on theory). That would be 6 months out of the year in most of the U.S. and year-round in a lot of the U.S.

If it's too cold for upright, and you can invert, then you need to be more careful about filtered canister or you'll clog? But maybe you really need to be able to clean your stove regardless?

I agree, no need for propane in the mix. But, I think it's easier for them to produce fuel that has a mixture of propane and isobutane. More difficult to refine it to have just isobutane.

If it just happened to be really cold one night (less than 25 F or so) then the propane would be pretty useful.

So, yes, you're over analyzing, just pick any canister. Unless you're inverted…

[Rick M]

del

[James holden]

jetboil fuel comes from korea …

as does MSR and snowpeak these days …

you can see it here …

http://www.mec.ca/shop/fuel/50495/?h=10+50035+50491

when in doubt just buy MSR … its 80% iso, 20% prop

and generally available

;)

[Roger Caffin]

Hi Kevin and Gary

Actually, I don't think Kovea actually make their own canisters – or rather, fill them. There is another company which does that, as I mention in the bushwalking FAQ:
'For instance, Dae Ryuk Can Co in Korea makes canisters for Kovea, MSR and many others.'

It gets more complicated that that: one company might make the canister while another one fills them. The Coleman Powermax canisters were made by … a USA company which makes (millions of) hair-spray canisters etc. But I don't think that company filled them.

If the canister says "made in Korea" or "made in France", it probably was. But companies sometimes change their suppliers, and that is what I suspect has happened here. The Primus Power Gas canisters were quite OK, but then they came out with these Chinese-sourced ones. These ones had 'Primus' and a couple of other brand names on them: very generic! But they had those crazy 2-decimal-places percentages on the cans, and afaik only the Chinese-sourced ones do that.

Sometimes it can take 6 months for the retail supply chain to reflect a switch, as shops usually buy canisters by the case load. They have to, as the canisters require special transport arrangements which are expensive. So in some areas you might not see the later Chinese ones for quite some time. Eh, if the retail market does not like them, some shops may never see them.

Cheers

[Bob Gross]

The cheap ones… would they be good as targets on the target range?

–B.G.–

[Jerry Adams]

"The cheap ones… would they be good as targets on the target range?"

Maybe throw in fire and see what happens?

I want someone else to try this. Set up video camera first. Make sure life insurance is paid up.

[Roger Caffin]

> The cheap ones… would they be good as targets on the target range?
You would need tracer for the best effects.

Cheers

[Aleksi K]

Replying to an old article, but this question has not been discussed so far…

The article starts with: ‘Liquid gasoline stoves are out – these systems are the realm of what we call “traditional” backpacking, or “just plain heavy”. With the new wave of integrated canister-heat exchanger systems and inverted (liquid-feed) canister systems, liquid fuel stoves are all but obsolete in our community.’

Then the article proceeds to report empty canister total weights for a three-person cook group in the range of 0.77 kg – 1.08 kg. Liquid fuel stove with a pump weighs 383 g, as said in the article.

What I’m missing here?

[Author]

Posts