Stove Systems for Winter Backpacking

The article is a good general coverage of stove performance in the winter.  Could you please comment on fuel consumption/volume requirements for your top picks?  For snow melting and such, I would image that pack volume starts to become significant.

I took an Alpinism course with American Alpine Institute last year in late July and it was led by two young guys.  They were very knowledgeable in technical climbing knowledge and skill.  Other things?  Well…

We were talking about how much fuel to bring onto Mt Baker and water availability.  Someone asked, “What if there’s no liquid water readily available and we have to melt snow?”  Their answer was that, “It doesn’t take much more fuel to melt snow than it does to boil liquid water.”

Hmm, someone has never heard of “Heat of fusion”.  I didn’t know the numbers but I knew instinctively, and from college physics/chemistry a long time ago, that it takes significant amount of energy to change frozen water from a solid to a liquid.  Looking up the numbers:

1L of frozen water is 1kg.  It takes 334 kJ to change 1kg of frozen water into liquid water (at 0°C) (according to Google)

It takes 4,180 joules to raise 1kg of water by 1°C.  So to take water from 0° to boiling (100°), it would take… 418kJ

So:  liquid water at 0°C to boiling:  418kJ

Frozen snow to boiling:  752kJ

80% more energy,  i.e. 80% more fuel needed.

I’m going back this year because I got food poisoning on day 1 and had to bail.  (They’ve giving me a significant discount to retake).  Lousy luck of mine…

Jon,

Absolutely!  It gives me new appreciation for when we’d use the MSR Whisperlite stoves and carry a big bottle of white gas.  Sometimes you really do need it if you’re melting a lot of snow.  It’s just too bad the stoves themselves are heavy.

Pretty interesting!

So far fuel pools inside the yellow aluminum block when one opens up the valve. The eventual base will have a cup or maybe just a fiberglass mat, as the stove is so small it preheats readily.

We also think that maybe it is rigid enough as shown and all we need, in addition to the primer mat, is a windscreen with spoke potholders, like this bigger Toaks and Firefly combo:

View post on imgur.com

View post on imgur.com

Dumb Question Department: What happens when you burn white gas in a spirit burner (alcohol stove)?

You create very yellow, sooty flames.  You have to design a passive stove specifically to burn White Gas.  I made one before and it burned a blue flame.  That being said, while the energy density is high, the actual burn rate was low.  It took about 12 minutes to boil 2 cups.  At the end of the day, it did not seem like there was enough of an advanatge to develop it further.  My 2 cents.

Altitude must be factored into equation. Oxygen for flames and stoves differs at sea level versus 3600 meters or about 12,000 feet.

After further investigation, I see that white-gas-in-a-passive-stove has been discussed at length in the past:

Why Isn’t There an UL Alcohol Stove That Burns White Gas?

A simple alcohol stove more fuel effecient than the Jim Wood Super Cat?

Takeaways:

• It can be done fairly easily: Zelph demonstrates it, Dan Y states decent efficiency. (Newbie Question: Are they the same person?)
• Benefits over alcohol are… meh. Overall, alcohol is cleaner and nicer to work with.
• I now understand Jon’s bottom line better (above). The efficiency advantage of white gas is mitigated by an unpressurized stove.
• I also see why Nunatak is doing it the hard way: It may work better in the end.

Nunatuk, prime the stove with alcohol. When I cooked with an MSR X-GK II, I took a small dropper bottle of alcohol for priming.  No smoke or soot. Kept the jet clean.

I like your old-school aluminum Sigg fuel bottle. Just like my old one.

For reference (in furlongs per fortnight, ah, I mean BTU/pound):

Wood 8000-9700

Methanol 9,739

Ethanol: 12,754

Isopropyl Alcohol (the other IPA): 12,960

Carbon 14,104 (as charcoal, not diamonds)

Octane 20,582 (a component of and proxy for white gas)

Butane: 21,282

Propane 21,638

Methane 23,867 (a.k.a. natural gas) can be carried compactly as a liquid at -260°F)

While looking at those reference charts, acetone looked interesting at 13,248 BTU/pound because that’s better than methanol, ethanol or IPA and is available in the cosmetics aisle of any grocery store as fingernail polish remover.  Acetone has twice the vapor pressure of those alcohols, so maybe that’s helpful in some burner designs at lower temperatures?  Also, TSA allows it on planes – the first thing I’ve noticed with some real juice that they allow (alcoholic beverages over 80 proof and even firewood is prohibited).  Limited to under 3.4 oz / 100 ml in a carry-on and 2 kg total in checked bags with no one container over 500 ml / 17 fluid ounces.  Two liters of better-than-alcohol should be enough for any trip.  Experiment at your own risk (due to that higher vapor pressure).  From my Svea and Optimus use in the 1970s I can reassure you that your eyebrows will grow back.

6 fluid ounces of Equate brand “100% acetone” nail polish remover is $1.05 at Walmart!  Same price per ounce as 91% IPA and cheaper than red or even yellow HEET.  For an AT hiker who is at Walmart anyway to resupply, 6 ounces for your next leg would be just right.

In reference to the comments above about whether one could build a passive burner white gas stove, the statement that a white gas stove requires a pressurized container and pump.

My recollection from reading about the Danish, Swedish and Norwegian polar expeditions at the turn of the century is that Nansen worked with the folks who founded Primus who designed a passive burner modeled on the marine alcohol stoves where the burner was on top of the fuel tank.  The Svea123 Safety stove with its cotton wick was a successor to this design.  I would estimate that the Swedish company Optimus and the US-based company MSR introduced stoves with remote pressurized tanks in the mid 1970s.

the minimum is to use two stones, is that right?

and then you put them in the pill bottle, pour in alcohol and let the stones absorb for 8 minutes?

then put the two stones on the gold disk, and put your pot directly on the two stones?

the alcohol evaporates out the sides of the stones and then burns and flames go up the sides of the pot?

how much does two stones and the pill bottle weigh?  how much does it cost?

interesting innovative idea

so the bottom of the pot touching the stones won’t get hot, but the rest of the bottom and the sides get hot?