UKH

I’m looking at gas canister stoves for very cold weather, specifically those that can do inverted canister for liquid feed. Does anyone know if there is a comparison of fuel efficiency of this type of stove anywhere online? 

Also interested in people’s experience of using these types of stoves in -20c and below, the good, bad and ugly. 

Thanks

Why not just get a liquid fuel stove?  

I would go for a gas or liquid stove in a Trangia windshield.  Trangia do their own gas burner and there are a couple of other stoves that integrate with it.  Edelrid hexon is one of the cheaper ones.

The enclosed windshield and pot really helps with colder weather but is a bit heavier than some options.  Whether it is worth it depends on how long you are out for.

To celebrate my 21st I went for an over-nighter to Glencoe camping with a mate in January to climb some routes on the Buachaille - after a session in the King's House, an uncomfortable sleep at -25C to find the gas frozen and no brew was a tough lesson. I've done a few, multi-day unsupported trips to the arctic in winter where it was well below -20C - having a non-functioning stove in those conditions isn't worth the risk. MSR multi-fuel stove has worked faultlessly for me.

Next time sleep with the canister in your sleeping bag. (Put it in a sock or similar if you don't want the thing right next to you.)

+1 for the liquid fuel option. I've got a Whisperlite and it's bomb proof in any temps. Gas canisters are really inefficient when its super cold and probably only worth carrying if every gram counts. In which case MSR reactors are the go-to. 

As mentioned already, the canister needs to be in your sleeping bag at night and inside your downie during the day. When boiling water it'll cool rapidly, at which point you plunge the canister in the water it's heating for a few seconds to bring the temp back up.

Even more sketchy but effective is the classic two stove method. Canister stove 1 heating water, while canister stove 2 heats canister 1. Switch every thirty seconds and everything stays warm and the water boils. Try not to die.

If you have a stove with a long hose you only need one.  Not dying is key.

Get a multi fuel stove and take a selection of both types of fuel. Also buy a fire blanket, 1m x 1m will do it. Place this under your sleeping mat at night for extra insulation/protection. When cooking drape the entire thing over everything, pot, stove and canister, leave a small opening. The trapped heat then keeps you canister warmer and keeps the wind out! Haven't tried it in anything below -10, but it made a big difference and its safer!

Not a good place to start...

It was all bad. The only time I used a canister in -25C it was rubbish and almost useless - though to be fair it was also at 6000m in Tibet.

OTOH I used MSR XGK fuel stoves in Antarctica for a decade in temps down to around -38C and never had a problem. I never cracked or broke the plastic pump.

I also have used an early model Primus Himalayan Multifuel, which has a steel pump, and I like it better than the XGKs though it's a bit heavier. It takes canisters, which is handy for Himalayan trips, but I have never used it in lower than -5C or so.

A friend recently aborted a mid-winter Brooks Range AK trip with temps down past -50C and had bad stove problems (MSR XGK and Primus) except with the Optimus Nova, which apparently worked great.

FWIW, I did field test a new (2012) model XGK v Whisperlite v Primus Multifuel in a simultaneous boil test in a tent vestibule in Antarctica in about -20C conditions. There really wasn't much between the XGK and Primus, the latter a tad faster, but the Whisperlite was considerably slower.

For what it's worth, I broke a Dragonfly pump when the bag it was in fell off a low bench. Pump was in the fuel bottle in a side pocket. Can't remember exactly what broke, but it was unusable, so take care and protect your pumps people.

I took my remote canister Primus Spider to Finland in February in temps down to -32c. Providing you can heat the canister somehow it is doable (canister in warm water from a flask is great), but it's not ideal. If you were going on a short trip I'd say just wing it but for prolonged cold weather snow melting get something like an XGK. 

In terms of efficiency probably the biggest waste of fuel is the gas in the canisters you don't end up using because to get the stove warmed up so you can invert the canister you have to run it for a minute or two, and if it's starting to run low the pressure is so rubbish it's not worth the fight so you just grab a new canister. Also even if you can get the stove running, in serious temps (-20/-30) the fuel is so thick the stove just didn't run smoothly. Like a said, feasible with skill but definitely not ideal. 

That doesn't work well at -20 as you still have to take it out of your bag the next morning.

Generally I think the idea is that once you get a remote canister stove hot enough it can then take a liquid feed, and so you only require the gas to be warm enough for the short time whilst you get the stove going.

Old school solution......

http://www.ademiller.com/blogs/climbing/2005/12/gear-the-alpine-bomb.html

I was going suggest exactly the same idea of a home-made heat-exchanger made out of flattened copper pipe. Long ago there was an article on a magazine (might have been Mountain Review?) which described this in detail.

Obviously no manufacturer would recommend their use!

Another vote for XGK

You need to consider what fuels you will likely use if you go down the multifuel route. I've used a MSR Whisperlite, Dragonfly and XGK. Always found myself using filthy kerosene as that's what's easily available in parts of Asia. The Whisperlite blocked by the second or third night, the Dragonfly lasted about a week before blocking, whilst the XGK manages easily a month before cleaning is necessary. I actually lost the needle from my Whisperlite whilst cleaning it in Tibet, which left my knocking on nomad tents asking to cook over their dried dung fires. If you expect to be using dirty fuel in cold temperatures then I would go for the XGK without a doubt. Multifuel is also more environmentally friendly because there are no empty cannisters to dispose of. 

For anyone reading this and considering splashing on a liquid stove... the XGK might seem a winner. But for me the Whisperlite is the favourite for how quiet it is.

While running an XGK in a tent I don't think it's that easy to have a normal conversation. XGKs are loud! Whisperlite you can chat away as you would with a canister stove.

May not be important to some but where the stove is running a lot (anywhere you're melting snow for water) being able to chat while brewing up and cooking is good for morale and worth more (to me) than the slight performance edge of the XGK...

Did you get the answer to your original post Susie?  You know what I would take when its super cold! (it doesnt come in a canister)

This and associated articles may be useful:

https://andy-kirkpatrick.com/articles/view/cartridge_versus_liquid_fuel_sto...

If you are going for the MSR liquid fuel route; upgrade to the 'MSR artic fuel pump', the regular one is not designed for the cold.

(Primus and Optimus do not have different types of pumps).

Personally more fan of the Primus and Optimus options (running the Primus multifuel and Optimus Nova my self). Pumps feel more robust, uses a leather seal (doesn't seem to fold over like the MSR rubber ones and don't tear in the cold when not properly lubed) and even the pot holders feel more solid. Although the shakerjet (cleaning needle) on an MSR is simpler. 

Thanks for all the input ; I’ve successfully used gas in -25 conditions in Alaska and have fought with my XGK so often it’s not funny (maybe it’s just too old) and not impressed with Reactors. Anyone have any comments on the Jetboil Joule or Millijoule or the Primus Primetech?

Somebody asked a question not dissimilar from yours a few months ago, my friend Dave answered with his experience in Alaska of using gas - very good from what I remember, he reckons he wouldn't use liquid fuel anymore.

Looked it up, see: https://www.ukhillwalking.com/forums/gear/lpg_gas_calculations-676788#x8704701 and https://www.ukhillwalking.com/forums/gear/primus_primetech_and_microntrail_sto...

Keep well hydrated. Chris Bonington would stop during the day to brew up on his Himalayan climbs to keep hydrated.

Don't breath carbon monoxide from your cooking stove:

http://zenstoves.net/COHazard.htm

In the mid 70's Off Belay magazine had an article on carbon monoxide production by camp stoves. They all put out considerable amounts. Very dangerous. As the flame contacts the cold pan combustion becomes incomplete and CO is formed. The lower the pot the greater the CO production. By raising the heigth of the pot so little flame contacts the pot CO production is reduced dramatically with only 5-10% loss of efficiency. This is a problem stove manufacturers and gear retailers have not addressed responsibly.

http://www.bushwalking.org.au/FAQ/FAQ_Monoxide.htm

"While backpacking in New Hampshire's White Mountains last winter, four members of our party of 12 complained of dizziness and nausea after supper. The symptoms were the same as as those associated with altitude sickness, but we were camped at only 3400 feet. All four men felt fine the next morning, and the incident passed without explanation. Several months later we found a small winter-stove and cook-kit combination at a low price at a local hardware store. We bought a stove and decided to try it out by cooking lunch in an office at work. After 30 minutes, we noticed we felt dizzy and were experiencing mild headaches. We smelled combustion odors and decided to test for carbon monoxide. Our suspicions were confirmed when we found carbon monoxide levels of more than 100 parts per million (ppm) near the stove. We recalled the complaints of the four men during our winter trip. Unlike the rest of the group, they had cooked supper inside their tent because of severe winds and a low temperature. We decided their discomfort probably had resulted from exposure to a high level of carbon monoxide produced by their mountain stove."

Cold Research Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts.

"Carbon monoxide (CO) poisoning is a common problem encountered in a wide variety of settings, including both suicide attempts and accidental exposures. Fatal CO exposure occurred in two young, healthy mountain climbers who succumbed to fumes generated by a small cook stove in the enclosed space of their tent at 14,200 feet on Mount McKinley. There is the potential for confusing mild to moderate CO poisoning with the signs and symptoms of altitude illness.

One Norwegian study (see Thomassen below) exposed 7 healthy young nonsmoking male subjects to 2 hours of melting snow with an Optimus 111 stove in three different tents at a campsite 200m (650') above sea level . They all ended up with COHb levels of greater than 20%. At that low elevation the subjects were already experiencing signs of CO poisoning from their burning stove and were subject to the possible long term neurologic damage and potentially deadly CO levels. Exposure to similar levels of CO at greater elevations is a sure invitation to a very dreary death."

http://www.spiritburner.com/

Here's a good article from Backpacker Magazine:

http://www.spiritburner.com/fusion/showtopic.php?tid/123/

excerpt:

"Since both altitude and carbon monoxide reduce the oxygen saturation of the blood, their effects are approximately additive. Suppose our winter mountaineers cook in their tent at an elevation of 5,000 feet, instead. The HbO2 saturation in their blood would be 95% (the normal amount at 5,000 feet) minus the 5% reduction caused by the stove, or 90%. They would experience drowsiness, lassitude and mental fatigue,
At 10,000 feet the mountaineers’ HbO2 levels would be 85% saturation. Headache, nausea and euphoria could ensue, and they could be in some danger.
At altitudes higher than 10,000 feet, exposure to levels of CO becomes very dangerous. At altitudes of 17,000 feet, the mountaineers could vomit and collapse.
These effects represent what typical mountaineers might experience under the conditions indicated. But they might vary considerably from one individual to another depending on physical condition, acclimatization to altitude and amount of exercise."

A simple experiment to test ventilation is to light a stick of incense next to the stove. The amount of incense you can smell will give a good idea of ventilation efficiency.

Carbon monoxide (CO) is so extremely poisonous that one needs to totally isolate the stove from the living area. An enclosed vestibule or separate chamber in the snow cave or just put the stove outside. Also a chimney system could take care of the problem and made out of aluminum foil and nylon could be very light weight.

Thanks Toby  , I organised that trip that Dave was on !