Cold Weather, Hot Meals & The Science Behind Gas Canister Stove Performance in the Cold

Article by MCN Ben

It's a cold fall morning as you muster up the courage to get out of your warm sleeping bag to make that fresh cup of hot coffee or oatmeal to get you going. You fire up the stove and notice the tiniest blue flame. You open the valve more and more, yet your little blue flame doesn't change, or worse, it goes out and won't light at all. Why! ? It worked great last night!

As temperatures fall across the US some new challenges arise for cold weather camping. Cooking meals or making hot beverages to keep you warm is one of them. The reason, canister stoves do not work as well in the cold because the liquid fuel inside the canister is at a temperature so low that it cannot boil or vaporize to it's gas form fast enough for your stove to burn efficiently, or at all.

So what's the boiling point?

Butane = 31F

Isobutane = 11F

Propane = -44F

Yes, propane boils at -44F.

The chart below shows the temperature and pressure relation to different mixtures of n-butane and propane.

Photo sourced from The Engineering ToolBox https://www.engineeringtoolbox.com/propane-butane-mix-d_1043.html
Follow the link or click the picture to see more charts and information.

All brands who make these have their special blend, but generally it's a mixture of n-butane (normal butane), isobutane (i-butane), and propane. 

If the temperature of the liquid fuel is below it's boiling point, then there's no vaporized gas for your stove to burn off. If you are looking for a winter specific mixture, look for ones that have a higher propane ratio or more isobutane. At the store we carry the olicamp brand that has 25% propane and 75% isobutane.

Most unregulated stoves were designed to operate best at 70F with around 40-50PSI. Temperature and pressure are proportional so as it gets colder, you'll have less pressure in your canister and a weaker flame. I know that both MSR and Jetboil make stoves with regulators on them. This will let them burn efficiently at lower pressures and give you the ability to fully control your flame from boil to simmer.

Pro Tip: Keep your cans warm! All of them...well...not the drinks.

Keep your canister warm by putting it in your sleeping bag with you at night. This will keep the fuel warm enough to vaporize/pressurize the canister to provide a good efficient burn to cook with or boil water. If you forget, you can warm it up with your body heat or even use one of those air activated hand warmers, carefully! They shouldn't generate enough heat to over pressurize the canister, but monitor the progress as it heats up. Don't overheat the canister. If they get too hot and over pressurize, they pop. Ask me how I know...

Photo courtesy of @strykerADV

Other alternatives would be using a liquid fuel stove like the MSR WhisperLite Universal Stove. You can actually still use the isobutane canister, but upside down so you're getting the liquid instead of the gas vapor feeding the stove.