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Evaluating what stoves to use for what lengths of trips
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Randy Nelson
(rlnunix) - F - M

Locale: Rockies
Re: luxury on 07/31/2013 23:16:49 MDT Print View

"Funny how we fret over a couple ounces in a stove system, then bring "luxury" items that can weigh over a pound."

That's why I fret over those combined ounces Nick. So I can bring along the 18 oz Slinglight that doesn't feel like a burden to carry but feels oh so good on my old, aching back. :)

Jake D
(JakeDatc) - F

Locale: Bristol,RI
Re: Re: Re: Evaluating what stoves to use for what lengths of trips on 08/01/2013 06:59:57 MDT Print View

"Hard to argue with that line of reasoning.

Funny how we fret over a couple ounces in a stove system, then bring "luxury" items that can weigh over a pound."

Yep, I have tried a cat stove on a few trips and it was not worth the effort and waiting. I used 1oz of denatured and it took quite a while for water to boil, even worse when it was windy with a windscreen that wanted to blow away. I can go from pulling out my cook kit to 1.5-2c water boiled in 4 minutes. Entire 280mi LT... zero resupply. Efficiency means different things to different people :)

Nick Gatel
(ngatel) - MLife

Locale: Southern California
Re: Re: Re: Re: Evaluating what stoves to use for what lengths of trips on 08/01/2013 10:07:51 MDT Print View

I normally use a Caldera GVP with Esbit set up. It works for me.

However, on the few times I have hiked with others, I was jealous of the handmade burritos made over a Giga Power, to include warming the tortilla over the flame before assembly.

I have used (and own) just about every kind of stove made. The Esbit works for me on most trips. My favorite stove is a Svea 123, which I rarely use these days. I would jump on a titanium version if it was light enough.

It is hard to argue the merits of some of the canister stoves. Light, convenient to use, and many options for types of cooking.

Bottom line, IMO, is to use what works for you. There is no BEST stove. For most people, a canister is going to be the best choice.

Harald Hope

Locale: East Bay
reminder of OP of thread on 08/01/2013 11:59:26 MDT Print View

"Alcohol stoves are light, but require 3x more fuel weight than canister stoves daily. I need 3.5 oz of fuel/day to boil the needed water for meals."

I want to remind, the original point of this thread was weight, primarily. That was the question.

As we've seen, this person was using a very bad stove setup probably with a bad screen, then comparing that to a commercial product, not a homemade tube with a crude valve attached. Since he's using a starlight, there has to be a massive error in either his screen setup or something else, the starlight is quite efficient, but not without the right screen setup. It sounds like significant user error to me, but it's hard to say without actually seeing the person setup the stuff and use it.

The point here is to compare roughly apples to apples, for example, a cat stove, jim wood style, is easy to make but very inefficient, just because it's easy to make doesn't mean it should be compared to a device that costs between 30 and 100 dollars, you should be comparing similar things, ie, a heavy canister setup to a heavy alcohol setup (say a brass burner, very heavy screen, etc), a medium weight canister setup to a medium weight alcohol setup, and, as MB pointed out, there is actually no option to compare a true UL alcohol/esbit setup with an UL canister setup because there is no UL canister setup due to the pot issue.

As I noted, this boils down to, heh, convenience, nothing else. It's sort of the difference between choosing a tarp or zpacks hexamid instead of a free standing tent.

The efficiencies in weight/fuel consumption are real, but they keep getting obscured because people use inefficient stoves with bad wind screens, then comparing those to manufactured stoves for canister containers, there's plenty of well made stove options out there, well, a few, that yield good boils, but the odds of you randomly coming up with such a setup yourself with no work or study or testing is not particularly high unless you very closely copy the designs for good systems.

The OP stated that alcohol stoves (an abstraction that does not exist in the real world, there are different setups that do different things) require 3x the weight of a canister stove, this is a false statement based on error, if he had gone out and bought a nice setup for alcohol, just as he did for his canister, then his efficiency / fuel consumption would be in the area of 8 gm gas vs 12 gm SLX per 2 cup boil, hardly 3x, in fact, only 50%, which is why the weight advantage does not exist, the container weighs that exact 50%.

I am ordering a remote canister stove so I can test the real world non fantasy efficiency of a gas setup, just out of curiosity, and to have one stove if high fire danger exists, I may also order a light firemaple top mount to see what wind does to these canister stoves.

I personally find it odd that UL backpackers preach endlessly about learning to subsitute technique and skill for heavier tools, then decide that doesn't matter at all when it comes to one component of their system, but this isn't religion and liking certain things to be 'easy' over other considerations is what I believe most backpackers do, you might also consider this next time you criticize a regular weight backpacker, who in general have decided, quite simply, they want it ALL to be easy, comfortable, and convenient, at the campsite.

I'll be updating the actual efficiency list however on my site so I can point to it whenever the false claims of less weight for canister stoves is raised here, just admit you like the convenience is my suggestion, and stop trying to rationalize it with false weight claims.

I believe, but I won't state it for sure until I test it, that some setups of canister may yield 6 gm boils, but I believe that will be roughly as difficult to achieve as a 10gm SLX boil, ie, that's the very maximum that can be achieved with a perfect setup. At 6 gm, or 8 days of 2x2cup boils, I believe you gain a tiny advantage of starting weight, but that vanishes the first day, and it's only going to be a few grams over alcohol.

It would be nice however for an apple to apple comparison to be made, ie, if you are going to compare a homemade inefficient super cat stove with a home made screen, with little efficiency testing etc, then please compare that to a home made canister burner, with little testing done, I think you'll find the results revealing then.

The key is to realize that these problems actually were solved a long time ago, the issue I believe is that there simply is not central collection of actual test results for most alcohol stove setups, and a lot of the testing done was simply bad, incomplete, and without enough information to test the results yourself.

I found this of personal interest because it's interesting to see how myths form around testing/engineering, and then how they propagate onwards, taking on a life of their own.

Nobody in general would argue against the convenience of using a canister stove, but oddly, many here argue against the convenience of using other gear that is comparably heavy and inefficient, if weight is the primary concern. It's probably just the faddish nature of gear stuff I would guess. Personally, I'm happy I did the work to test this, I had long suspected that there was exactly zero weight advantage to using canisters, now I realize, of course there cannot be, due to the canister weight, and I believe, the actual lower efficiency of the gas burner, which at 8 gm boils is I believe a touch worse than a 12 gm alcohol boil.

Edited by hhope on 08/01/2013 13:48:26 MDT.

Harald Hope

Locale: East Bay
Posted full table, more complete on 08/01/2013 17:52:26 MDT Print View

I created a more complete table of backpacking fuel consumption/stove weight/pack weight.

That table covers 1 to 13 nights, and two types of alcohol stoves, an Ion type very efficient setup, at 60gm, and a penny type stove, at 70 gms, the penny type uses roughly 20ml to boil 2 cups, so I thought I'd that as another option, that's for faster boils, and should reflect a fairly wide range of stoves that boil faster but less efficiently.

I also added another canister weight category, 220 gm, and also compared using 2x100 on a trip longer than 6 nights.

The first time the starting weight is greater for an alcohol stove is for the penny at day 12, but then only for the first day.

Of course, always you return with less weight with alcohol since you bring what you need, and use it mostly up by the end of the trip, so the only time you ever will see any weight advantage over a less efficient alcohol stove is on trips greater than 11 nights, and then only on the first days, after that you carry much less.

I'm curious to learn a few other facts, like the actual fuel consumption of canister stoves for simmering, I saw some really bad numbers online, but I am interested to see what realworld use shows. I'll run some tests once the stove I ordered arrives, and also see if I can nudge down the per boil consumption of a canister stove in real world conditions, to my eyes the initial note of 24 boils of 2 cups per 100 gm canister, for 8 gm/ 16gm per day seems very realistic and in line with the relative consumptions of alcohol stoves. In a sense, to be truly fair, I should also create a 20gm per day canister boil, since that's a number I often see, to compare to the 32gm per day penny boil, ie, a not particularly efficient but probably common outcome.

I'll update this table as I get real data, but I don't think there's any actual doubt about the weight issue, the convenience is whatever it means to the person using it, silence to me is golden, so nothing could possibly improve on a silent stove.

Edited by hhope on 08/01/2013 17:59:54 MDT.

James Marco
(jamesdmarco) - MLife

Locale: Finger Lakes
Re: reminder of OP of thread on 08/01/2013 20:52:48 MDT Print View

Actually, it isn't even 1/3.

Wikopedia has the heat values for common fuels.

Butane is listed, but not n-Butane, one of the isomeres.

Anyway: (Note: all values are appriximate)
Methanol is 9800BTU/lb
Ethanol is 12800BTU/lb
Butane is 20900BTU/lb
A typical alcohol fuel is SLX. It's about 50/50 so I will just average the heat values. This is rough and could be off a much as 50BTU.
For the Alcohol Fuel: 11300BTU/lb.
For Canister fuels(butane): 20900BTU/lb
For carrying a usable quantitity, most use a small plastic bottle (8floz)that weighs an ounce.
For carrying a canister, it is the can. It weighs about 3.3oz (it varies by manufacturor up to about 3.8oz.) So for 100g of fuel we have about 94gm of container. So,by simple proportions, we have about 53% of the total weight as fuel.
Multiplying .53 * 20900BTU/lb gives us the total heat value: 11077BTU/lb after adding in canister weight.
After adding in the one ounce bottle for 8oz of alcohol (or 1 ninth of the total weight, we have 90% * 11300BTU/lb or about 10700.
The difference is only 377BTU/lb.

Comparing to canisters (377/11077) or about 4%. Not the 1/3 you had posted.

Roughly speaking, the carry difference is only a bit under 10%, not 33.3% as you stated.

alcohol on 08/01/2013 22:51:43 MDT Print View

The most important aspects on alcohol to me are:

1) carry only what I need
2) simply and easily, visually see how much fuel I have
3) Silent operation

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: alcohol on 08/01/2013 23:18:22 MDT Print View

" 3) Silent operation "

The leak is silent also.


Nick Gatel
(ngatel) - MLife

Locale: Southern California
Re: Re: alcohol on 08/02/2013 02:18:36 MDT Print View

"The leak is silent also."

Not to mention it is hard to see the flame and spills can happen easily with some alcohol stoves. Esbit doesn't require a container, other than a large Ziploc bag. Doesn't spill. Not sure of the weight of Esbit versus Alcohol, but it might be less per boil. Only problem with Esbit versus Alcohol on a long trip is availability. A Graham Cracker Esbit stove weighs less than an alcohol stove.

Maybe Harold can add Esbit to his chart.

James Marco
(jamesdmarco) - MLife

Locale: Finger Lakes
Re: Evaluating what stoves to use for what lengths of trips on 08/02/2013 04:48:16 MDT Print View

Zen Stoves is fairly good. It will take a full day to go through that site, though.
Note that it uses the lower heating values. Roughly the same proportions, though.

Harald Hope

Locale: East Bay
esbit and maybe white gas on 08/02/2013 11:31:41 MDT Print View

James, I'll add the zenstoves link, I forgot about them. The key however with contained energy is that that number, as I learned when testing stoves/fuel extensively, then finally rereading the sgt rock stuff on testing/results, is almost but not completely irrelevant, because what actually matters is the efficiency of the cook system. As you can see in this thread, due to some unknown user/operator error the OP is using far more alcohol than he should be using.

The alcohol fuel consumption numbers I'm citing are quite precise, measured, reproducible, and fairly heavily tested, and include moving air because I use a fan. I'm going along with the numbers cited for canister stoves because I believe people know when they get 12 2 cup boils out of 1 100 gm net canister, that's easy to track, so that gives 8 gm. I've also seen routine reports of 10gm boils with canister stoves, and I know that in theory you can get better efficiency. Ethanol gives a 100% efficiency of about 7gm / 2 cup boil, with best ever reported 10gm, I can duplicate and repeat 12 gm easily, so that's the number I use. For faster boils, you drop efficiency but sometimes speed matters more, yet as you can see from the chart, you still basically never carry more weight except the first day(s) of > 12 day trips.

Nick, if you provide me with true esbit numbers for a measured 70F water start true measured 2 cup boil I will update the chart. Obviously, as you note, there will only be the stove/screen weight, and toss on a ziplock bag to keep it fair. Keep in mind I am using mid weight setups, so be fair in the stove/screen weight, if yours is the lightest possible, that only competes with an MB type UL alcohol setup, so give the weights of a decent screen at 15gm and a reasonably robust stove. The trick though I believe with esbit, correct me if I am wrong, is that you will usually pick either an amount of water to boil that works with one or two of the tabs, or you will break a tab in half, or something. To be fair it has to be 2 cups, and then note the weight of each tab, and how many you use for the boil, that's what you would use in the field. Obviously esbit is easy to cite efficiencies for since the only weight is the fuel. I'd use for the middle case that type of stove that keeps in the liquified esbit as it burns as the middle case stove myself since that is clearly efficient but not strange.

While you can measure water temp, it's not truly necessary, just burn what you need to raise a rolling boil, that's close enough to 212 to not matter. If you post the results here I will update the chart. I will also update using my whisperlight because I believe the numbers are way off for that too.

Now that I have all the night 1 to 13 rows, it's fairly easy to update the chart, but do make sure your data is not total best case, be realistic since this is about what you carry, not what happens in your kitchen.

MB, I agree with your 3 pluses, majorly. Another thing I'd add to that is the ability to also gauge quite accurately extra fuel requirements. If I assign 1oz per day of consumption, that is precisely what I will use, and if the water does not fully boil, that's fine, it's hot enough. There's no way you can get that accuracy with gas, it's just going to be a guess each time, though experience certainly would show over time roughly what you can expect, but you will not know for certain. I could see the last days of a long trip being quite nerve wracking, heh heh.

While I am ordering a canister stove to further test, can anyone here do a 30 minute simmer test on a gas stove and let me know how much fuel that consumed by weight? I believe that you can basically toss your gas stove out the window once you start simmering, like a whisperlight, in comparison to alcohol, but I'd like to be sure.

I can add another table with simmer data, that would be useful, but do make sure to actually weigh the fuel. esbit clearly cannot simmer unless there is some setup I haven't seen that does permit that, maybe there is.

BobG, I have in fact spilled alcohol by accident on a trip, but that was due to a stupid design error I had made, I had inserted an o ring onto the bottle to 'prevent leaks', not realizing that created a gap where if you did not jam the top on super tight, it would leak, and it did, but that exposed the MB noted advantage, I was able to note how much fuel I had left, and then use that much per meal for the rest of the trip. You'll note in the charts that you end with zero fuel at the end of the trip.

In real world use of course I'd bring an ounce or two extra, something you cannot do with canisters, which is another advantage, say 6 days, you want a cup of hot tea in the evening? no problem, add 6 gm per day fuel, or a bit less.

Nick, I'll trust any results/weights/consumption you give me, but I have found the stuff online is not very reliable, in fact, some of it seems completely removed from reality, so I'll wait for your results to add that. Remember, stove/stand/screen weight plus storage bag, then tabs/weight of esbit per day. If the tabs include packaging include that weight to be fair.

Harald Hope

Locale: East Bay
MB, re pots on 08/02/2013 11:51:34 MDT Print View

MB, by the way, it's irrelevant what pot is used in this chart, because you can assume it to be a constant, however, you are also totally right to note that no high heat gas system can use a true UL pot because it will destroy it, so there is a level of UL that only esbit and alcohol can reach. I'm not going to cite that however because it would not be fair (since the system then would include the pot weight, and the pot weight used is not knowable in any chart), I am not counting the pot weight in these systems because you can more or less exchange those, with the exception of white gas, that requires a wide pot, a penny type side jet too really benefits from a wide pot as well. Personally I would not use a plastic lined aluminum beer can for a pot, but that's just my personal feeling on that matter, I do also see the attraction. I'm just noting this because you had written that using a heavier pot invalidates using alcohol, it does not, basically you cannot go heavier than canister unless you go with a white gas whisperlight type setup, the pot does not matter.

There is one further variable of course, wide pot vs narrow pots, and that will matter on probably most of the systems listed, but it also depends on the stove type. I may test on that too but it's a fair amount of work to do it so I'll hold off for now.

It's also worth noting that if you reach the max efficiency possible with canister gas, the real comparison then has to be the max efficiency with alcohol, so those proportions will not change all that much, what would change is possibly the range you can go with a canister, ie, the number of nights, but if you also go more efficient on alcohol stove setup, that difference should not matter much.

peter vacco

Locale: no. california
Re: Posted full table, more complete on 08/02/2013 12:08:28 MDT Print View

at one time in bpl past of long ago, we had a chart .. no .. a matrix of data about this issue. it had weights, atomic mass, use rates of boil, a zipstove, ambient temperature of the environment, and it all corrilated to How Long it was going to take for a given system to pay back itself. this electronic document was an edifice to Clear Thinking. it was a thing of analistic beauty. and it was just about useless too. because it did not include the Coolness Factor, a figure vastly more important than any lack of weight ever could be.

ie : how can we ever rate the rush of burning powdered coal found on an arctic gravel bar in a bushbddy. (well, you could rate it -$129, because it ruined my BB)


Harald Hope

Locale: East Bay
so true on 08/02/2013 13:15:17 MDT Print View

Peter, it would not be fair to include the coolness factor, that simply would raise the bar too high against all white gas and canister products. I mean, you walk into camp, whip out your ion, set it up, in a few seconds, fill it, light it, and sit back, content, looking up at the stars, or early morning sunbeams piercing the fog that will lift in a few minutes, if it's breakfast.

Another camper wanders by, and cannot help but wonder why you are sitting in front a of a silent screen with a pot on it, which then after a while starts to bubble merrily, but silently. The camper asks, where did you get that? and you reply, somewhat nonchalantly, I made it.

So best to leave the coolness factor out I think, otherwise the tests simply would be too skewed towards the alcohol setups. I'm trying to be as fair as I can possibly be here, to avoid bias and other factors.

stoves on 08/02/2013 23:11:50 MDT Print View

I do think its fair to include the weight of a UL pot, because the difference is equal to 4 days fuel for me, not inconsequential.

I have never had an alcohol leak, but I primarily use flip-top nalgene bottles. I dont suffer any noticeable loss of alcohol stored in it in a closet for months either so its fairly vapor tight. If I use a PET bottle to carry extra fuel, I tape the lid on with a wrap of electical tape.

Of course I do try to keep it always stored upright in my pack, just in case. No sense tempting fate.

My alcohol stove (tealight cup) , weighs 0.07 oz. I dont know of anything lighter. Yep, that is LESS than the graham cracker at 0.1 oz.

I dont need to see flame, I know where it is. Its in the cup. BTW you can see alcohol fine if its dark. If in doubt, just place palm above cup a few inches and feel for heat, its not rocket science.

I think you can get slightly better efficiency with esbit than 0.4 oz alcohol boils for 2 cups, its obviously a hotter flame and boils slightly faster. I have gotten about 0.3X oz I recall. But saving the little fuzzy bits, and trying to reuse is kind of messy. Always a tradeoff. Some of the weight that is left may not qualify as fuel anymore.

Edited by livingontheroad on 08/02/2013 23:14:48 MDT.

Harald Hope

Locale: East Bay
heh, no, you don't get it on 08/03/2013 12:36:32 MDT Print View

MB, you can't include it because it's not fair, as I noted, there is no canister/white gas setup that will support that pot weight, and the pot weight is constant in any case. It is worth noting the full weight of the basic cookset however, at a minimum, maybe I'll add some tables for that, but that won't change consumption weights/carry weights for fuel, so that would make a decent table on its own.

Fuel Consumption / Carry weight table

Pots differ in size and capacity, by not including the pot weight you allow for that, but it is certainly worth noting and also is correct that you cannot get as light as a fully UL beer can cook pot, but to me that's not a pot, I can't eat out of it or cook in it, so it doesn't have the same functionality.

With freezer bag cooking, by the way, you must include the full carry weight of the freezer bags as well, since that is an integral part of the cook system.

However, this is a fringe area, and doesn't impact the efficiency of the boil beyond the actual differences in pot/stove setup efficiencies, which are real ( could improve the alcohol numbers for wide pots, for example, my tests are all with narrow pots), the fact remains that alcohol is virtually always lighter, and it makes no difference what pot is used to make that determination. The pot weight is a constant, as is the stove etc weight, so you simply add/subtract that weight to the listed weights and there you have it.

But I am also glad you brought that point up, because it shows that there is a category below, ie, less than, in weight, all the listed categories, that only esbit/alcohol can support, let's call that a SUL category. ie, There are only esbit/alcohol SUL setups (and wood, of course). That's a fair thing to note. But don't forget the freezer bags in the weight.

While this is, as Peter noted nicely, a bit anal, the fact is, trying to do something resembling science, with empirically verifiable results, is always boring in the end, it requires a lot of tedious data collection etc. Some of the tables I found online, including from bpl, are so far removed from reality that I didn't even link to them, whatever they were measuring, they did it wrong. For canister results, the info online is pretty easy to confirm, because it's so easy to weigh/setup a canister, you buy the burner and the canister light it, boil, weight. However, Ryan Jordan, in a review of I think a fire maple UL burner, noted clearly that wind is a huge factor, just as it is with alcohol, so people who try to claim some advantage re canisters and wind are kind of cherry picking the case. I tend to trust Ryan's findings in general, so I won't question those. Makes sense afterall. I suspect the whisperlight however has a powerful enough flame and a good enough wind screen to not have to worry as much about wind, I know I cannot remember ever having even given wind issues a thought when I used xgk/whisperlight, nowhere I ever used it, in any climate, and I was in pretty bad weather with that thing.

I'm going to test white gas next, because I suspect that white gas may actually be the lightest weight on a super long trip, not positive, but it may be, but we're talking very very long, 3, 4 weeks. Well, actually, because I have it sitting here, heh. But again, only on the first days. I also just want to see what it does if I treat the testing like any other weight/efficiency testing, full boil, stop, weigh consumption.

Edited by hhope on 08/03/2013 12:44:29 MDT.

Paul McLaughlin
(paul) - MLife
Re: Posted full table, more complete on 08/03/2013 12:36:49 MDT Print View

Harald, thanks for the work on the chart.
So all of this seems predicated on solo use. Am I right? Curious to see how things look for two, with double the fuel usage per day, and assuming a single larger pot to accommodate boiling 1 qt at a time.

Ken T.
(kthompson) - MLife

Locale: All up in there
Re: Posted full table, more complete on 08/03/2013 12:55:33 MDT Print View

Here is one from 2006

Harald Hope

Locale: East Bay
it's all linear on 08/03/2013 12:58:32 MDT Print View

Paul, one of the things I had to painfully relearn from high school chemistry is that the energy required to raise x weight of water y degrees F is a constant once you calculate the efficiency of the stove/fuel type/screen/pot setup. So, if .8gm SLX raises 2 cups of water 10F, which is about what it does, it makes no difference what the starting temp of the water is, for example, as long as it's liquid. So if you are boiling 4 cups, it's going to take 1.6gm SLX to raise that water 10F. The issue however then will be boil times, it's just going to take a long time to boil it (20min or so), and I think that's one reason people go with gas in that case.

If you go less efficient, like a side jet burner type stove, or a penny jet stove, or a variety of other types, then you need about 32 gm to boil 4 cups from 70F, and it will take about 12-15 min depending. I don't think I'd try to use an ION type efficient stove for non solo use, except for morning coffee or whatever with more than one person. But note that even with the less efficient category, you still do not exceed the first day carry weight using alcohol until the 22nd or so 2 cup boil.

This difference is part of the 'convenience' aspect of canister/white gas stoves, and it's certainly valid, but it has zero impact on the weight carried numbers of fuel, as with everything, you get to pick things, weight, convenience, speed, and picking one will nullify another.

However, I would suggest to people who have come up with fairly ridiculous stove efficiency numbers for their alcohol setup, like 3x more fuel required, or 1oz to boil 2 cups, that they take a look at their alcohol setup and either go out and support one of the fine stove / screen vendors out there, or figure out what they are doing wrong, to my eyes it's like me turning on the canister jet and letting it burn a few minutes before putting the pot on then complaining about its efficiency, or burning it in a high wind with no screen. As sgt rock told me, focus on the screen, not the stove, though the stove type does matter as well. Alcohol setups should be sold as a unit, and fitted to the pot diamater/height, that's I think the main reason cone setups get the efficiency, they are sold as one, same for the flat cat gear stuff.

Steve Martell
(Steve) - MLife

Locale: Eastern Washington
Re:Evaluating what stoves to use... on 08/03/2013 12:58:54 MDT Print View

Nice work Herald. Like many other hikers, I've noticed it's hard to beat the many advantages of alcohol stoves--

*Silent operation
* lightweight
*no stink (vs. Esbit)
*no residue (vs. Esbit)

About the only time canisters win the weight advantage is when snow melting is needed, for larger groups (>2) or more complex cooking (simmering, etc.).