Stove choices

Hi Reginald

There are MANY articles on the BPL web site covering canister stoves and their use in cold weather. There are also quite a few articles here on alcohol stoves. Have a browse.

The bottom line is that white gas (and kero) stoves are the heaviest option of the lot, and of no merit under most any circumstances.

Alcohol or canister? Ah, the debate rages!

Cheers

Actually, alky stoves are affected by winds more than either canister or white gas. However, I've used my alky in high winds and altitudes with great success. Supplementing my windscreen with a couple of well-placed rocks to further block wind was a no brainer.

I usually bring a bit more fuel than normally needed — but at elevations of 11k or 12K — I did not notice any significant increase in alcohol fuel requirement. If anything, winds are a greater determining factor — but as above, winds can be managed.

3-season trip – short duration – alcohol stove.
3-season trip – longer duration – canister stove.
winter trip where snow melting is required – white gas stove.

Hi Ben

> winter trip where snow melting is required – white gas stove.
I am curious as to why you say this. White gas stoves are heavier than canister stoves, even winter ones. White gas fuel weighs more than butane/propane. You always use more white gas than butane/propane for any task.

Yes, I used to use a kero stove for many years. Before that, a LONG time ago, I used white gas, but friends had a few accidents with it which burnt some of MY gear. I gave up on that fuel. Now, even when melting snow, I prefer a canister stove these days.

cheers

Hi Roger:

I find it very inefficient to use a canister stove in cold temps — with cold condensation building up quickly on the fuel canister. Maybe the detachable ("remote line") canister stoves work better because they can be positioned upside down, but I have no experience with those.

With appropriate windscreens alcohol or the standard canisters should be fine for you. Altitude has no negative performance impact on the canister. I haven't seen a significant performance impact to alcohol due to altitude.

I typically use alcohol on my solo three season trips… and not had a problem, though I have found them too slow when cooking for more more than myself or when I have to melt snow.

Upright canisters work great down to about freezing. I have had luck down to around 10F with care to pre-warmed the canister (keep it inside my jacket for awhile, sleep with it). I had troubles when colder than that or when I needed to run the stove for an extended time to to melt snow: because the the pre-warming lost it's effect as the air temp + the release of pressure cooled the canister.

If you are really worried about cold conditions and need a lot of power I would go with one of the discontinued Coleman powermax extreme stoves which you can still find around or go with one of the stoves that using the more common canisters turned upside down to run on the liquid + vaporizing tube rather than the vapors strait from the canister.

I wouldn't recommend white gas. It is the heaviest solution and they are fairly temperamental from a flame control / servicing the stove perspective.

Hi Ben

How did your trips go this summer? I'm gearing up for another possible trip in the near future, so I'll be frequenting the forums a bit again.

I've always stuck with cannister stoves (recall my PocketRocket vs. LiteMax tests?), but now I'm considering alcohol stoves. I'm curious to know which design you are using.

Shoot me an email some time.

David

Hi Ben

> I find it very inefficient to use a canister stove in cold temps — with cold condensation building up
> quickly on the fuel canister.

Yes indeed. You are talking about 'upright' canister stoves here, and they are NOT intended for use in cold weather for this very reason. You can use them, but it takes several tricks which may not always work well.

> Maybe the detachable ("remote line") canister stoves work better
Trust me, they DO! Experienced winter/snow campers do this all the time. I have written several long articles for BPL about doing this. Go on, buy a subscription and read them!

An explanation: many stoves can burn both white gas and liquid canister fuel. There is very little difference between these fuels apart from their boiling point. Modern multi-fuel stoves are all heading this way. Yes, alcohol is a *different* fuel.

Cheers

Roger — makes a lot of sense! Thanks.

David — I just sent you an email.

Reginald,
My wife and I were in the Winds mid August this year and we used a
caldera cone with the gram cracker and esbit. It worked great. I don't see why alcohol shouldn't work just as well. We used a sul 1100 and averaged less than 1 1/2 tabs per meal. The only addition I would have made is possibly a little gel for starting. My lighter didn't work real well on cold mornings.

IMHO, white gas stoves get a bad rap.

Look, the reality is that there's a 4-ounce difference between the MSR remote-canister Windpro and the WhisperLite. You will have unquestionable service with the WG stove. Regarding safety and ease of use of WG stoves: I've used them for twenty years without a single accident, without any equipment damage, or burns, or spilling of hyper-cooled fuel in winter. I don't accept those as significantly valid arguments against WG stoves. Any forum other than BPL would suggest the WG stove. There is the 4 ounce weight difference–your decision on how significant that is.

Compared with an alcohol stove, I think you'll find that the WG would be much more efficient and hassle-free for melting snow, etc.

Remote canister definitely the only way if you want to go canisters. It/they will work for you, with inverted canister and (preferably) a preheat device of some sort. Are you willing to modify a stove to make it work optimally? Or are you looking for an off the shelf approach?

To be clear, I'm working on a UL remote-canister Frankenstein stove myself. I do like them and find them viable alternatives. But I think we're too quick to dismiss anything WG when, really, the WG stoves are optimal for winter conditions. I think it comes down to a ratio of cold weather performance: heat output/efficiency: weight. Which of those variables is most important to you?

Some statistics for the record:

An 8oz/227g empty canister weighs ~138g
An 11oz empty liq. fuel bttl weighs ~90g
The empty liquid fuel bottle is 48g lighter than canister.

The canister has ~227g of fuel.
8 fl. oz. of WG weighs < 227g (don't know density- .85?)
The liquid fuel is nominally lighter. (If density:0.9, then WG weighs ~204g).

75g weight savings w/WG fuel (2.65oz)
then
113g (4oz) weight penalty of stove minus
75 g (2.65oz) weight saving of fuel equals
38g (1.34 oz) weight penalty for WG system

Under ideal conditions, per manufacturer:
227g canister: 15L boiled
8fl oz WG: 12L
Seems like edge to canister for efficiency–except canister efficiency affected by fuel temp, whereas WG basically isn't

And from Snowpeak, Isobutane "can be ignited at 14 deg. F" With a 30% propane mix, not sure how low that can go. (And not sure why they don't say. I have observed performance declines in upright canister systems at ~38F. Obviously different w/inverted canister.)
WG will ignite at whatever temp you have.

It seems to me that w/30% Iso/Pro mix at temps below 14F you'd be burning the propane, but not the butane. Is this accurate?

At any rate, for a roughly 1.34oz weight penalty for a WG system to a non-aftermarket remote canister, I feel that the utter reliability of WG is superior. (Yes, this makes the assumption that the boil times are a wash. I'd be pretty surprised if they're not…)

To conclude, what I think we need–and what has been discussed in other threads at some point–is to develop a UL WG system.

Thoughts?

Brad – at less than 14 F at sea level, you would indeed be burning mostly propane. At higher elevations the mix that actually boils off in the canister with have more iso-butane than at sea level, but it would still favor the propane at those temperatures. This is with a new canister.

A half empty canister of MSR fuel (80% iso-butane, 20% propane when new), if burned at a constant 35 F, will be 91% iso-butane. And when only 25% of the fuel remains in the canister, it is 97% iso-butane. So performance drops off as the canister level drops.

With inverted canisters this is not true – the composition remains constant throughout the life of the canister, and since there is no significant evaporative cooling in the canister (no vaporization) performance remains constant.

Brad, what about going to the Simmerlite instead of the Whisperlite.

True, it doesn't simmer any more than the Whisperlite whispers, but it does save you 65g and mine has been just as reliable as my old Whisperlite.

> 8fl oz WG: 12L

This may be so if you turn the stove on and leave it running. But when you take into account the hassles of priming each time, the real figure might be closer to 8 L in my experience.

> except canister efficiency affected by fuel temp, whereas WG basically isn't
True for upright canister stoves. False for inverted canister stoves down to about -20 C. Below that you need to use a couple of tricks – which are quite possible. See
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=13468&skip_to_post=123612#123612

> WG will ignite at whatever temp you have.
Oh NO it won't! You have to vaporise it before it will ignite! And it takes a higher temperature to vaporise white gas than canister fuel.

> It seems to me that w/30% Iso/Pro mix at temps below 14F you'd be burning the propane, but not the butane. Is this accurate?
Completely wrong, thank heavens, for any inverted canister stove. You get the mix as stated on the canister.

The somewhat unknown truth is that white gas and butane/propane fuels are extremely similar. It is just that the butane/propane mix vaporises at a far *lower* temperature than white gas.

Just don't try to use an upright canister stove in winter conditions – but there are plenty of technical articles on this web site about proper use of winter stoves.

Cheers

Hi Don!

Cheers
Roger

With my old Whisperlite no matter how slow I could get the flame I could not make it use less fuel than a canister stove (See graph below).

Stoves used: MSR Whisperlite, Trangia and MSR Pocket Rocket. These test where done at 20C. I get similar results from Inverted canisters as with upright canister stoves.

Roger’s FAQ fuel mixtures has some good information on canister pressures and temperatures.

Tony

Hey, Roger! I haven't been around much of late.

As for efficiency, I use significantly more fuel when using white gas than when using a canister stove – twice as much by weight. It's not a completely fair comparison, since I often use an Outback Oven with the white gas stove in addition to my normal cooking, but even when doing the same cooking I use less fuel with the canister stove.

The fuel, as Roger said, has a very similar energy content on a weight basis, so the efficiency comes into play with stove design and priming.

Roger-

I haven't measured how much fuel I use to prime, but it's very little, and in my experience it certainly wouldn't account for 4L less boiled. That's huge!

I'm familiar with cold-weather canister tricks. Don't like sleeping with them; need the stove to light to warm the water. Too much hassle for me.

Perhaps I'm using the term incorrectly, but WG will certainly ignite at whatever temp I've used it, down to about -30C. Vaporization occurs after the priming process, certainly not right when it's lit. But it has always lit, whereas my canisters haven't always.

Don, if I understand properly, also believes that the propane/isobutane will separate at those temps–obviously remaining in the canister at given percentages, but only some burning. I seem to have observed this separation in uprights. Does the simple process of inverting the canister somehow change the physics of gases in the canister? Like I've said elsewhere, I'm an English major! :P

Rod, yeah, a SimmerLite would be ideal IMO. If my calcs were anywhere near close, you could actually end up net lighter than the WindPro winter setup! I'd like to try to make a lighter SimmerLite somehow, maybe get rid of legs by using combined windscreen/pot support. Don't know about other metals to use…

>"An 11oz empty liq. fuel bttl weighs ~90g
The empty liquid fuel bottle is 48g lighter than canister."

???What about the weight of the pump needed to pressurise white gas??

I have been terrified many times by other folks white gas stoves. It's especially scary when you are in a wooden hut!! You may argue that it's because they don't know how to use them properly, but it's amazing how many people fit into this category. Ergo I conclude that white gas stoves are a hassle and potential hazard compared to cansiter stoves. I often hike with some friends who use a Whisperlite, which is identical to our WindPro except for the fuel source. We always have a boil long before they do, mainly because we don't muck around with pumping, priming, and flare control. We just turn the knob and light with a match. Voila.

Hi Brad and all

> I haven't measured how much fuel I use to prime, but it's very little, and in my experience it certainly wouldn't account for 4L less boiled. That's huge!
Yes, that's huge. But I have records of fuel used, weighed to 1 g each time, going back maybe 10 years and covering both kero and butane/propane canister gas (b/p). I have been budgeting on 30 g/day of b/p for years for the two of us. Before that I was using 50-60 g/day of kero, and white gas is very similar to kero.

Part of the reason people don't realise how much white gas they are really using is that it is so easy to just 'top up the fuel bottle' before a trip. I know – I used to do that too, except that I then weighed the fuel bottle and kept records.

> WG will certainly ignite at whatever temp I've used it, down to about -30C. Vaporization occurs after the priming process, certainly not right when it's lit.
Oh, sure, it will light AFTER the priming process. The same can be said for b/p of course, only priming it is even easier imho. Liquid water over the canister is enough to prime it.

> the propane/isobutane will separate at those temps–obviously remaining in the canister at given percentages, but only some burning.
This is not exactly correct, as Don will confirm. What happens is that the propane will continue *boiling* off long after the butane has stop boiling. The two gases do not actually 'separate'. It is a fine point I realise, but there have been many passionate arguments on the subject!

> Does the simple process of inverting the canister somehow change the physics of gases in the canister?
YES, YES, YES!

With an upright stove the fuel in the canister boils and the vapour goes up to the stove. At -20 c there is very little butane coming off the liquid inside the canister, so the vapour going into the stove is maybe 95% propane. You could call that 'preferential boiling' if you wish. The propane runs out after a while, leaving mainly butane.

With an inverted canister the propane in the canister pressurises the fuel (like pumping a WG stove) and the pressure pushed the original butane/propane mix down the hose. The composition of the fuel in the canister stays constant. There is no 'preferential boiling' in the canister.

This is EXACTLY the same as what happens with a pumped white gas stove. EXACTLY the same. White gas is a mixture of hydrocarbons just like butane/propane.

This is all spelt out in far greater detail in the Winter Stove articles already published here at BPL.

Cheers

What Roger said.

There is no physical separation of butane and propane in the canister. It remains a mix.

Mole fraction in the vapor = mole fraction in the liquid * vapor pressure (in an ideal mixture, which is not too far off for a butane/propane mix). As the liquid vaporizes, the fraction of the vapor that comes from the various fuel components is a function of each component's vapor pressure.

Propane has a much higher vapor pressure than butane, and this difference becomes more significant as the temperature drops (the ratio of vapor pressures increases). So you end up with mostly propane molecules vaporizing, and the butane mostly stays behind. The fuel actually fed to the stove is higher in propane than the liquid from which it came. The result with an upright canister stove is that the fuel enriches in the heavy component (butane in this case) as you consume fuel, which makes performance drop as the canister level drops. Exacerbating this is the fact that vaporization in the canister cools it off (lowering vapor pressure), further reducing stove performance unless you use tricks to keep it warm. I have done this – using almost pure butane at about 20F, but you have to do things to keep it going.

An inverted canister feeds liquid fuel that is pressurized by the mixture's vapor pressure. Since there is no vaporization (or very little, only enough to make up the volume of liquid fed), the composition of fuel fed to the stove is the same as the composition in the canister. The composition thus does not change as the fuel is consumed, and the performances stays the same throughout the life of the canister – and the canister is not cooled by vaporization.

As Roger pointed out, this is the same as a white gas stove, except the inverted canister uses the vapor pressure of the fuel to get it to feed to the stove, while the white gas stove uses air pressure created by pumping the stove (white gas vapor pressure is not sufficient to do this on its own).

As for priming, unless you measure it you are probably using more than you realize. And the stove design makes a difference. Stoves that prime easily (Optimus Nova or MSR Dragonfly) require less fuel to prime than the Whisperlite (I have a DF and Whisperlite, and I have seen the Nova in use).

White gas can be ignited down to its flash point, which is normally pretty cold. But it has to be heated to its boiling point before the stove can burn it – only the vapor burns, not the liquid. As long as you can ignite it you can prime the stove and get it hot enough to run.

Roger, Don- Thanks. I now have the vaguest recollection of vapor pressures and such from some long-ago class. I think I get that part now.

Don,
"White gas can be ignited down to its flash point, which is normally pretty cold. But it has to be heated to its boiling point before the stove can burn it – only the vapor burns, not the liquid. As long as you can ignite it you can prime the stove and get it hot enough to run."
Yeah, that's what I was ineloquently trying to say.

Allison, the weight calculations include the weight of the pump with the stove weight. Come on, now! I'm not going to count the weight of the pump twice!

Cheers-

>the weight calculations include the weight of the pump with the stove weight. Come on, now! I'm not going to count the weight of the pump twice!

>75 g (2.65oz) weight saving of fuel

???Where did this number come from??

>38g (1.34 oz) weight penalty for WG system

I'm just not understanding how you only get a weight penalty of 38g with the WG. The base weight of a Whisperlite is 305g plus 90g (395g) for an empty bottle. The Windpro is 193g plus 138g (331g) for a difference of 64g, not including differences in fuel efficiency.

You and many others ae quite happy with your white gas stoves, and that is great (please don't burn down the hut I'm sleeping in though). But as a forum focused on lightening up, it is difficult for me to see how a heavier, less fuel efficient stove that needs priming and often flares, would be preferable to the same stove running off of canisters.

For those of you that shy away from the Windpro because it can't be inverted, think again. The cable is long and flexible enough to turn the canister upside down. I do this every time I use the stove.

>what I think we need–and what has been discussed in other threads at some point–is to develop a UL WG system.

I'm waiting for the commercial production of a UL remote canister system…soon!!!

Thanks Alison.

I'm very interested in the Windpro, as a safer/easier option for when I'm walking with the family, and for the ability to run it as an inverted cylinder in the snow.

However, as I posted earlier, I think it's a bit erroneous to compare it to the Whisperlite. The Simmerlite is essentially the same stove as the Windpro, and probably offers the best option to compare WG to cylinders.

I finally pulled mine out of the shed and put it on the scales. Mine is nice and sooty (another problem no-one has mentioned, meaning it's not really viable to NOT use a stuff sack) and there's probably some fuel in the pump. The stove weighs 183g plus 60g for the pump, for a total of 243g. Add 90g for a bottle is 333g, or a 2g penalty.

Now we start to come into decisions based on efficiency, cost, and convenience. (And safety, if we want to go there)

EDIT:
Okay, since I had the stove and scales out, I also tried priming it.

Outside temp is 16C, 62F. There's a slight breeze. I weighed the bottle, pump and fuel at 371g before starting.

I pumped about 8 pumps into the full 11oz bottle. The Simmerlite tends to push liquid fuel onto the burner head rather than directly into the priming cup. I allowed the WG to wet the burner head, and then lit it. No flare up, although the breeze pushed the 5cm flame around a bit. This burnt off but the fuel was still not vapourising. I let a bit more out, but this time it also dripped down into the priming cup. I lit the head and cup. Again I wouldn't call this a flare up, but flames were now about 7-10cm above the burner head.

This preheating vapourised the fuel to the extent that I was able to light and burn for approx 20 sec with the familiar choofing as the preheat tube comes up to full heat. I prefer to allow this to heat using vapourised rather than liquid fuel to prevent flareups.

I then turned out the flame and reweighed the bottle, pump and remaining fuel. It was now 369g. I have to admit I was a bit surprised by this. I would have expected to burn more like 3-4g to prime.

I do know that it's much easier to prime the Simmerlite than my old Whisperlite, probably because the flame is directly under the preheat tube. Weather conditions are very mild, and I know I have to use more fuel in the snow, and this is a once off, not measured over a number of years as Roger did, but I have to admit it has made me more impressed with the Simmerlite, rather than less.

It wasn't supposed to work this way!! :^)