Performance Of Alcohol Stoves in the Cold

[Odd Man Out]

I see many threads here asking about alcohol stoves vs canister stoves. From the posts it seems there are many myths about alcohol stoves, especially about cold weather performance. I thought that since we were in the midst of a polar vortex, it would be a good night for some testing. I ran two tests - one in my kitchen on one on my deck. For those not interested in all the technical data below, the executive summary is as follows. At room temperature, my system boiled 2 cups of room temperature water in 4 minutes using about 14 mL of alcohol. Outside with the air, fuel, and stove all at 2 degrees below zero F, the power and efficiency of the stove was unchanged. The only effect of the cold was that it was hard to light (I just dropped the match into the stove) and it took about 50 seconds longer to get started).

Technical Stuff:

The system is a DIY easy Capillary Hoop Stove (1.5" tall), an Olicamp XTS pot with lid, an aluminum flashing cylinder wind screen (4.5" tall with radius 1/4" larger than pot, lots of air holes around the bottom), a stainless steel hardware cloth pot stand (3 1/8" tall - bottom of pot is 1/2" higher due to the pot's heat exchanger), everything sets on aluminum foil (for protection) and a plastic cutting board a table. The volume of fuel to boil the water was calculated from the formula: mL to boil=total mL fuel x time to boil/time to flame out. Both tests used 2 cups of water and 25.0 mL of fuel (50:50 ethanol/methanol). For the outside test, the stove and fuel temperature was -2 F. At this temp, alcohol doesn't "poof" into flames when you light it, so I just dropped the match into the alcohol which worked fine. I can't see the flame during the test, but based on the sound and the water condensing at the top of the wind screen, it seemed to take about 10 seconds for the stove to get going in the kitchen and about 60 seconds outside. The volume of fuel to boil calculation assumes a linear burn rate which I know to be a reasonable approximation inside, but it probably isn't for the outside test due to the delay in priming. Since the time to flame out, the time to boil, and the time to prime were all delayed by about the same amount, I conclude that the power of the stove (inversely proportional to boil time) and the efficiency of the stove (inversely proportional to volume of fuel to boil) for both tests were about the same once the stove got going. If I subtract 10 seconds from the inside times and 60 seconds from the outside times to adjust for the time to prime, then the power and efficiency of the stove running outside were both 96% of the inside test. Thus the only effect of the cold (72 degrees F colder than room temperature) was a 50 second delay in starting the stove.

Here are the data.



Test

Kitchen

Outside



Ambient Temp (deg F)

70.0

-2.0



Wind Speed (Furlongs/Fortnight)

zero

negligible



Initial Water Temp (deg F)

70.0

68.0



Initial Fuel Temp (deg F)

70.0

-2.0



Time to Boil (Min:Sec)

4:00

5:00



Time to Flame Out (Min:Sec)

7:15

8:05



Volume of Fuel Needed to Boil (mL)

13.8

15.5



Sanity of Tester


Questionable

[Mags]

Alcohol stoves are terrible water boilers in cold weather and take much too much alcohol to melt snow..so much that the weight savings is lost.

That is not a myth. The fact that warm water was used is not very realistic for true winter backpacking conditions as well.

Canister stoves are only marginally better than alchie stoves in cold weather UNLESS an inverted and remote canister stove is used.

Even those stoves start showing performance decrease around 0F..esp if very cold water is heated and/or snow is melted.

Setting up a stove on your back porch, while using warm tap water, is probably not the best demonstration of winter backpacking conditions.

If warmed up in your jacket, alcohol will work somewhat even in frigid weather...but, again, for any extensive melting of snow or even heating of a lot of water...forget it.


[1] Yes, they use alchie stoves at Iditarod aid stations. But these are essentially huge, ginormous buckets of alcohol. Who cares about efficiency when the fuel is not carried? :)

[MuddyWaters]

Alcohol works fine in cold. It doesnt light off as well due to lower vapor pressure, but heat output (burn rate ) depends on heat feedback from flame, and 30 degrees or so of ambient temp really doesnt affect that much, as you saw. You want methanol for higher vapor pressure than ethanol, it will light better. Keeping it warm will help too.

However, winter conditions usually result in more camp time, more desire for hot food and drinks, colder water. Melting snow or ice might also be necessary. These things can alcohol poor choice. Its time for the whisperlite for many, or an inverted cannister. All depends on trip length and conditions.

Im an alcohol fan, but it wouldnt be my first choice for a week of snow camping in sub-freezing conditions. Cold nights, warm days, no problem.

[Connie]

There is a great deal of information and discussion on these matters over at bplite.com forum, by the way.

The Companion stove zelph built melts snow. I have done it and I am impatient about hot water in cold weather.

I never start with 70 F water, even in Summer. I start with 50 F water or colder mountain water.

My recent acquisition, the Cobalt Blue alcohol stove has a strip that heats all layers of the alcohol, a design feature that works very well in Montana cold weather. I set it directly on the snow, just for fun.

I don't usually go into all this detail. It never comes up in an ordinary conversation.

This stuff works.

zelph has the time to boil 2 cups water, the time to flame out, all that stuff for comparisons.

I like having options: I can use whatever heat source at a time that pleases me.

I find I am not desperate for hot water or hot food.

[CarlZ993]

I had trouble a time or two lighting my alcohol stove (Zelph's Fancee Feast Stove) during the cold, early parts of my AT hike. I had to either use a hurricane match or dip a stick into the fuel & then light the stick to light the stove. But, I did get it to work. I didn't time it. But, it seemed slower than when I tested it back in TX.

If I needed to melt snow for drinking water, I'd pass on an alcohol or canister stove. I'd go w/ a white gas stove. I don't have any scientific data to back up my biases. :)

[Traveler]

I had trouble a time or two lighting my alcohol stove (Zelph's Fancee Feast Stove) during the cold, early parts of my AT hike. I had to either use a hurricane match or dip a stick into the fuel & then light the stick to light the stove. But, I did get it to work. I didn't time it. But, it seemed slower than when I tested it back in TX.

If I needed to melt snow for drinking water, I'd pass on an alcohol or canister stove. I'd go w/ a white gas stove. I don't have any scientific data to back up my biases. :)

I would say experience is the best guide in winter use especially. I use white gas fuel stoves in the winter months pretty much exclusively. Though I am sure there are conditions that I could fuss with an alcohol stove in near 0 weather in the wind, or my canister stove would work, the risk and consequence of failure pretty much makes the decision easier. The weight difference is worth the relative reliability in my view, especially if you are cooking/heating water for two people.

[SteelCut]

If I needed to melt snow for drinking water, I'd pass on an alcohol or canister stove. I'd go w/ a white gas stove. I don't have any scientific data to back up my biases. :)

I think your biases are well founded. I've melted snow for 6 clients on multi-day winter mountaineering trips in the CA Sierras. There is no way that I'd use anything but white gas for this. Even then, it's alot of work.

[LoneStranger]

It all depends on what you are trying to do. Making tea for a day hike is a lot different than melting snow for six days of water supply. AT hiking with a resupply every three days is a lot different than a two week back country loop with no resupply. There is a tipping point where alcohol becomes too inefficient both in terms of temperatures and number of days. You can still use it, but that doesn't mean there aren't other options that would be better.

I was happy to see this thread though because I could hear a stove fight getting ready to break out in that other thread yesterday and a good stove fight is usually even more entertaining than a hammock/tent fight :)

[russb]

No matter your choice of stove (really we are talking fuel choice) in winter, be sure to have a backup plan. A few years ago on a winter mountaineering trip my buddy's white-gas stove had a failure. My alcohol stove became both of our stoves for that evening. In general all stoves are back-ups for me as I will use a wood fire as my primary (even if it is just a small twig fire).

[The Solemates]

well thanks for posting your results. i perform tests like this all day every day. i think there were several flaws in your DOE, but I dont really care....I prefer real life experience. All I know is that this past weekend I was finished drinking coffee and eating a warm meal after using my liquid fuel stove before my buddy even finished cooking. It was 9 degrees and 20 mph winds.

i have several stoves, and pick the one I want to maximize efficiency based on my trip. sometimes this is a pot on a bed of coals.

[Connie]

For me, sometimes it is a JetBoil.

I have also been known to carry a thin and light thermos for hot water in the morning.

I like to get moving early in the morning.

[Odd Man Out]

I had trouble a time or two lighting my alcohol stove (Zelph's Fancee Feast Stove) during the cold, early parts of my AT hike. I had to either use a hurricane match or dip a stick into the fuel & then light the stick to light the stove. But, I did get it to work. I didn't time it. But, it seemed slower than when I tested it back in TX.

If I needed to melt snow for drinking water, I'd pass on an alcohol or canister stove. I'd go w/ a white gas stove. I don't have any scientific data to back up my biases. :)

My intent was not to suggest that alcohol stoves were the best choice for melting lots of snow, cooking for lots of people, etc.. The test was just to demonstrate that alcohol stoves (at least certain ones) can function pretty much normally in very cold conditions. As always, the best choice depends on what you are doing. If you were going out for a weekend when springs are running but weather may be below freezing, then this kind system might make sense.

Also, the type of alcohol stove makes a difference. Most alcohol stoves function by thermal feedback to heat the pool of fuel in the bottom. Putting this type of stove on a cold surface or putting a pot of cold water directly on top of the stove will act as a big heat sink and cut down on stove performance. However an eCHS stove doesn't have these limitations. It doesn't require vaporization of the fuel in the bottom of the stove and the pot does not rest on the stove.

[Connie]

I also think people missed the point made zelph has an added metal strip in many of his alcohol stoves that help heat the layers of alcohol that occur in really cold weather. He also have larger capacity alcohol stoves. His spill-proof Companion stove has 4 oz. capacity. He has added another 4 oz. capacity spill-proof alcohol stove, now.

[Slo-go'en]

The main trick to using an alcohol stove in the cold is to insulate it from the ground. I've had good luck by making an insulted stove holder out of a tin can like a Dinty More beef stew can. It also doubles as the pot stand. I drill 1/4" holes all around the top edge of the tin can and some around the middle for air flow. I then set the stove into the tin surrounded with fiberglass insulation.

[Mags]

My intent was not to suggest that alcohol stoves were the best choice for melting lots of snow, cooking for lots of people, etc.. The test was just to demonstrate that alcohol stoves (at least certain ones) can function pretty much normally in very cold conditions.

..with warm tap water on the back porch. ;)

Being serious, I do not see the validity of this test or similar ones.

The Solemate's example seems a bit better of a world real world example.

Alchie stoves can, and have, been used in colder weather esp for a quick boil and cook meal. But that's atypical of winter use. For deep winter, there are better tools to use for something beyond "lab only" examples.

[Fireonwindcsr]

I'm using HEET and a metal recept

[QiWiz]

I have used alcohol fuel to heat 2-3 cups of water for solo cooking down to an air temperature of -5 deg F and water temperature of just above freezing (from a mostly frozen stream or water container buried in the snow) with no trouble other than lighting the stove (tip: dip a twig in the alcohol, light twig, hold near surface of alcohol or side of stove until stove catches; insulating stove from ground helps too) but agree that it takes too much alcohol if you have to melt snow. In that situation I would either use a wood burner (if that were an option) or a white gas stove.

[Connie]

I prefer my zelph Companion alcohol stove for melting snow. It holds 4 oz. alcohol that will not spill out, so I can't tell you how much is left over.

I don't want the hottest flame there is for melting snow because I want to minimize the chance of scorching the snow. Scorched snow has a horrible taste and odor. The pan takes on a horrible odor.

It is necessary to start out with water in the cookware and get it hot, before dropping in snow, to avoid scorching the snow as it is.

zelph has a more horizontal aspect 4 oz. alcohol capacity stove now I might like even better.

I have been using the alcohol fuel Companion stove with his folding wood stove.

This is so I could ho either way: twiggy fire or the Companion alcohol stove.


Mags, we don't have the altitude you have in Colorado but I assure you in Montana we have COLD.

[300winmag]

IF YOU MUST USE ALKY IN WINTER:

Use a Caldera cone for the greatest thermal efficiency.

OR
Use a Tri-Ti or Sidewinder titanium Caldera cone with the Inferno gassier wood burner. VERY hot and good for melting snow. Use ESBIT tab chunks for tinder.

For 3 season use I use a Sidewinder, mating hard anodized aluminum 3 cup pot and Brian Green modified fuel tab holder for greater efficiency and lower fuel weight than alcohol. This is THE most efficient ESBIT system available. Believe me, Iv'e tested a lot of them.

[zelph]

Shug demonstrates the Companion Burner used for melting snow with the BushBuddy wood burning stove.


https://www.youtube.com/watch?v=KiPp2ZvL3h8



Shug uses the Fancee Feest alcohol stove in -40 degree weather.


https://www.youtube.com/watch?v=CTuGJgka1qc

[Another Kevin]

Alcohol stoves are terrible water boilers in cold weather and take much too much alcohol to melt snow..so much that the weight savings is lost.

That is not a myth. The fact that warm water was used is not very realistic for true winter backpacking conditions as well.

Canister stoves are only marginally better than alchie stoves in cold weather UNLESS an inverted and remote canister stove is used.

Even those stoves start showing performance decrease around 0F..esp if very cold water is heated and/or snow is melted.

Setting up a stove on your back porch, while using warm tap water, is probably not the best demonstration of winter backpacking conditions.

If warmed up in your jacket, alcohol will work somewhat even in frigid weather...but, again, for any extensive melting of snow or even heating of a lot of water...forget it.


[1] Yes, they use alchie stoves at Iditarod aid stations. But these are essentially huge, ginormous buckets of alcohol. Who cares about efficiency when the fuel is not carried? :)

Mags, my answer is 'maybe'. If I did the sort of winter travel that TW does, I'd want a white gas stove - they win, hands down, for melting snow and extended winter use. But I don't do extended winter backpacks. Weekend trips and peakbags are more my thing.

For a weekend, I'm fine with alcohol. Never had my Penny Stove fail to light, and I've melted snow on it before. I do have to use a priming dish to get it going well, and a wisp of alcohol-soaked TP sometimes even to get the primer to light, but light it does, and the water boils. I cooked a couple of meals on it just a month ago in subzero temps with water that had frazil in it when I poured it in the pot.

For a winter weekend, I might go through 12 oz of alcohol instead of the 3 I might use in the same time period in summer, partly because I'm doing a lot more boils, for soup and tea and suchlike. Oh well, alcohol is lighter than water, the 12 oz volume is about 9 oz weight. How much weight would I add carrying a white gas stove and fuel bottle, or a remote canister? At least a few oz. For longer than a weekend, yeah, the weight penalty would start to add up rapidly. But I don't do that.

(And I'd also argue that most hikers don't. For most of us, even a thru-hike is a succession of long weekends strung together.)

So: You're right. And I think I'm right, too, but I'm answering a different question.