Fuel consumption for a new stove setup

[blacklab2020]

I am switching to a hanging stove setup and have always relied on white gas in the past. With the new stove (MSR Superfly ascent system), it runs on butane, isobutane, isopropane, etc. I will be using isopropane for its advantages over butane (higher vapor pressure, burns hotter). The canisters will be warmed by a chemical heat pack.

I am curious about the typical fuel consumption required to melt dense snow to boiling. When using white gas it wasnt uncommon for two of us to use nearly 20 oz of fuel to cook and melt snow to boiling water each day. That was roughly 6-7 liters of water.

I know I cant get an exact answer for many reasons... temperature of fuel, ambient air, pot conductance of heat, style of cooking, etc. I would just like to get a feel for how much I should bring on an overnight or a 2-3 night winter trip... even a 6 day winter trip.

Thanks,
~J

 

[KayakDan]

I generally allow for a cannister of fuel(smaller Primus cannisters) per day for cooking and snowmelt for the two of us. Just as important is bringing a good windscreen tfor your stove,but be carefull not to wrap too tightly as the cannister will heat up rapidly.
As you mentioned,the conditions will make the fuel consumption vary.

 

[blownaway]

I would carry a dependable white gas stove on the first trip or two and just experiment alitte with the superfly. Hanging stove systems sound great on paper but they require some care and attention when used inside a tent....and it sounds to me like that's your intended use...

Ive made my own system but I used white gas.....I rigged up a coleman stove and a household pot using thin wire....Have used it flawlessly at times, and have also dumped pots of water on the tent floor other times....not to mention melting the screen vent in the top of my I-tent.....

The butane/isopropane is much safer inside but from what Ive read...they dont function as well in cold temps....so they require attention...heat packs, pots of water, copper wires...etc....Screw it...I like to put 1 - 2 liters of water on the stove and nap in my bag for 8-10 minutes and buff....boiling water at your service.

Just less hassle to cook outside or in a vestibule with stove on the ground....plus you gotta lugg 2-3 empty cannisters around with ya for 3 days....I'd rather burn up extra weight with each meal...

 

[blacklab2020]

I always carry two winter stoves... i was hoping to use the white gas blow torch for melting water if needed. I am gearing for the hanging setup for more technical ascents... ledges with not enough room etc.

As far as the butane canister is concerned, I will be trying to use chemical heat packs for that.

I was just looking for an initial estimate for the butane/propane... An initial condition if you will, Somewhere I could start experimenting with...

Thanks for the tips.

~J

 

[blownaway]

"I would just like to get a feel for how much I should bring on an overnight or a 2-3 night winter trip... even a 6 day winter trip."

Technical? Ledges? Winter?

You can get the best advice from Chauvin Guides.....But unless I was hanging off the side of Half Dome I would stick with ONE dependable white gas stove with repair kit. Two stoves for 3 or more people...but one should be plenty for two people (although its nice to have your climbing buddy melting snow while you cook/make hot drinks etc.)

Chauvin makes the idea of using a hanging stove sound so romantic, but they are rarely used below 32 degrees in the northeast. I have the superfly but would only want to REALLY depend on it in the warmer seasons...

 

[blacklab2020]

yes... use on portaledges, high sierra trips, british columbia etc.

not entirely in winter, but also when i prefer to be cooking in a tent rather than being being blasted with 40+ mile an hour winds...

its a matter of preference... maybe my mind will change with time.

 

[blownaway]

To get a more concise answer you need to be more specific.....You started out with a winter question and fuel consumption required to melt DENSE SNOW. Now the sierras and not necessarily winter?? Are you melting snow or what?

Spring-like conditions and no snow melting.....1 8oz cannister should last 2 days (2 people) unless your prepping gourmet meals...

Melting snow in winter.....2 people, 3 days/2 nightss, ready to eat mountain house meal and tea.....20 to 0 degree F temps.....I personally would bring 4-5 cannisters on first trip.....prob 3 would do but an extra wouldn't hurt....

******Also, MAKE SURE you test the cannisters before you leave....the threads could be damaged and not thread onto your stove.....

Checkout the weight of each one to verify fullness...

4-5 Cannisters----Just too much bulk for winter.....I would much rather use the space too carry something else.

 

[Miss Margaret]

I tried keeping a cannister warm with a handwarner-in-a-cozy combo last winter - about 0 degrees? In the Dax last winter. Used a piece foam pad under it for additional insulation.

DID NOT WORK. Canister was too cold, couldn't maintain the pressure. Luckily, we had a backup (white gas).

I've also read about Chauvin's hanging set up, but after my experience, not sure I'd trust it (although disclaimer, I wasn't hanging mine). Certainly wouldn't go out without a backup the first try.

Margaret

 

[blacklab2020]

"Melting snow in winter.....2 people, 3 days/2 nightss, ready to eat mountain house meal and tea.....20 to 0 degree F temps.....I personally would bring 4-5 cannisters on first trip.....prob 3 would do but an extra wouldn't hurt...."

Thank you. Thats all I was looking for (fuel consumption). Not a discussion on my choice of gear. If it doesnt work, I will have been forwarned... If it does I can only pleasantly be suprised.

If you really need to know my specific climbing agenda, please PM me.

~Justin

 

[NYBRAD]

Estimating Fuel Consumption
Canister: Difficult — you need to weigh canisters to determine how much remains.

White Gas: Easy — simply turn off the stove and look in the tank to see how much remains.

As you ascend in elevation, atmospheric pressure decreases and water boils at a lower temperature. For every 18 °F drop in the boiling point of water, it doubles the time to cook food. For example, the boiling point of water drops from 212 °F at sea level to 194 °F at 10,000 feet. It takes twice as long to cook raw food at 10,000 feet than it does at sea level. So, if you are planning to cook raw food at higher elevations, be sure to bring extra fuel. For boiling water and rehydrating foods, altitude doesn't make much difference. It actually takes a little less time and fuel to boil water (since it boils at a lower temperature), but rehydration will take a little longer, which balances it out.
Reduced exterior air pressure improves gas flow, even at low temperatures in cans.. Convenience and no need for priming are assets in cramped high-altitude tents, and when people are functioning below par due to altitude effects.
Although canister gas provides really light heat for short trips, on longer trips with more canisters, the weight of the canisters soon mounts up and makes the stoves heavy overall.

Cold Weather Performance

Canister: Not great once temperatures approach freezing, better when fuel contains propane and uses iso-butane instead of n-butane as the main component of the mix. Coleman X series is currently best, Primus Himalayan works fine if canister is inverted carefully as in the instructions to provide a liquid fuel feed to the burner. Work better in the cold at HIGH altitude.

White Gas: Performance unaffected by cold. Coleman/ Peak 1 models need priming with paste or alcohol. Pump pistons can become stiff and seal poorly when cold, but friction during use soon overcomes this, especially with plastic pumps.

Bottom line,
It's hard to guess on consumption and
the only application I can see from a hanging stove is on Big Walls and Ledges at very high elevations.