I'm still sticking to the opposite of ice 9. Ice 6?

JD wrote:

96avs01 wrote:Define cold...

It's interesting to hear that you found it useful in Alaska, presumably in the height of summer when the sun is higher in the sky than in the Sierra winter. I wonder though, how much did it really save you in fuel or time?

Didn't have a comparable stove setup to quantify the savings (fuel or time) simultaneously. The time saved was noticeable (vs. other trips without using a bag, or days where we were moving and couldn't leave a bag sitting in the sun all day), so one could propose using time as a surrogate that fuel savings would've been somewhat proportional. At sunup we'd put the sealed bag (loose overhand knot) on top of a staked closed cell foam pad. When we returned from our day's activities several times we gleaned over 1L of melted water and always significantly more consolidated snow than we left in the morning.

Melting snow is a big chore for climbing Rainier. My son and I had to stay at camp Muir for three days, waiting out a storm that lashed the peak with 100 mph winds. I wish that I had a black trash bag to melt snow since that would have saved a pound or two of fuel, along with the tediousness of tending the stove and worrying about CO poisoning while doing stuff in the vestibule. I almost had a tent burn down while camping on a January Mt. Washington trip. Wisperlite stoves have some fuel valve issues! In that case solar energy would have been useless for melting snow.

Honestly I wouldn't buy any specialized snow melter unless I was planning a 10 day+ expedition like Denali. I estimate 8 oz of fuel per person per day. The survey could use a bit of tweaking to get meaningful market information.

That makes perfect sense, Spiderman. Are you sure you're not running for President

96avs01 wrote:The time saved was noticeable (vs. other trips without using a bag, or days where we were moving and couldn't leave a bag sitting in the sun all day)...

I was hoping for something a little more quantitative even if it were a rough estimate. But "noticeable" is something. And there isn't much cost to doing it other than the time spent shoveling some snow into the bag.

Any idea what the ambient temperature was?

ExcitableBoy wrote:I'm still sticking to the opposite of ice 9. Ice 6?

They actually both exist, although they go by Roman numerals, e.g. ice VI and ice IX. And they don't have the properties you're hoping for.

Although I'm not sure you'd really want them to. If you recall from the Vonnegut story any water that came into contact with an Ice 9 crystal transformed into Ice 9, kind of like with King Midas. Or certain prion proteins. So it wouldn't be such a great idea if your plan were to climb snow or ice. Or to have a margarita.

JD wrote:

96avs01 wrote:The time saved was noticeable (vs. other trips without using a bag, or days where we were moving and couldn't leave a bag sitting in the sun all day)...

I was hoping for something a little more quantitative even if it were a rough estimate. But "noticeable" is something. And there isn't much cost to doing it other than the time spent shoveling some snow into the bag.

Any idea what the ambient temperature was?

When I get home next week, I'll see if I can find my trip journal (it's got some measurements we took on the trip).

JD wrote:

ExcitableBoy wrote:I'm still sticking to the opposite of ice 9. Ice 6?

They actually both exist, although they go by Roman numerals, e.g. ice VI and ice IX. And they don't have the properties you're hoping for.

Although I'm not sure you'd really want them to. If you recall from the Vonnegut story any water that came into contact with an Ice 9 crystal transformed into Ice 9, kind of like with King Midas. Or certain prion proteins. So it wouldn't be such a great idea if your plan were to climb snow or ice. Or to have a margarita.

Ice 6 or Ice VI would have the opposite properties of Ice 9/IX. It would be liquid and would de-crystalize snow and ice when it touches it. Obviously the issue is if it is spilled on the glacier, the entire glacier would instantly turn to water creating a lahar that would destroy everything down hill of it. Eventually it would reach a river, which would drain into Puget Sound, then the Pacific Ocean then it would melt the ice caps. I can definitely see the downside. Perhaps just improving the efficiency of stoves would be a potentially less global catastrophe inducing approach.

The MSR Reactor and their ilk are incredibly efficient compared with non stove system stoves. I have an MSR Pocket Rocket and I created a simple heat exchanger by crimping an MSR windscreen, switching to a black anodized aluminum 1 liter pot that is relatively tall. These minor changes seemed to improve efficiency by around 25 percent, gauged in terms of melt/boil time and fuel used.

ExcitableBoy wrote:Obviously the issue is if it is spilled on the glacier, the entire glacier would instantly turn to water creating a lahar that would destroy everything down hill of it.

You wouldn't have to spill it. If you drank any then a single drop of sweat or the condensed moisture from your breathing would have the magic properties. And since, unlike Ice 9, the magic wouldn't be due to a particular crystal form (Water 6?) it would also likely be present in the vapor phase. So just uncorking a vial of it would quickly transform the entire world.

ExcitableBoy wrote:The MSR Reactor and their ilk are incredibly efficient compared with non stove system stoves. I have an MSR Pocket Rocket and I created a simple heat exchanger by crimping an MSR windscreen, switching to a black anodized aluminum 1 liter pot that is relatively tall. These minor changes seemed to improve efficiency by around 25 percent, gauged in terms of melt/boil time and fuel used.

I'd love to see a picture; and also have some more details about how you measured the improvement and under what conditions.

I've measured 55-60% efficiency indoors with just a plain pot on a stove. I've tried windscreens and also one suggested homemade heat exchanger and they didn't have any effect in indoor tests. But where fuel efficiency really matters most to me is outside in the winter where heat loss is greater and fuel needs are higher. I don't know what my canister stove's fuel efficiency is when melting snow at 10°F. But a 25% improvement in those conditions would be worth some extra weight, at least on trips longer than a few days.

Looks like the guy with the opening post has abandoned this discussion since about day one.

mrchad9 wrote:Looks like the guy with the opening post has abandoned this discussion since about day one.

He/she/they didn't abandon it. The OP was never part of the discussion. They just wanted people to take their survey.

JD wrote:I'd love to see a picture; and also have some more details about how you measured the improvement and under what conditions.

I've measured 55-60% efficiency indoors with just a plain pot on a stove. I've tried windscreens and also one suggested homemade heat exchanger and they didn't have any effect in indoor tests. But where fuel efficiency really matters most to me is outside in the winter where heat loss is greater and fuel needs are higher. I don't know what my canister stove's fuel efficiency is when melting snow at 10°F. But a 25% improvement in those conditions would be worth some extra weight, at least on trips longer than a few days.

I will have to take a photo of the setup, I thought I had one, but it must have been on my laptop, which met a premature demise.

My 'measurements' are purely anecdotal. I think you hit the nail on the head, the setup definitely makes a bigger difference in cold and/or windy conditions, as the heat exchanger tightly wraps the pot and fuel canister, very effectively blocking wind and also channeling heat back to the canister to keep it warm. The manufacturer says that is a big no-no, but the canister never gets above barely warm to the touch, as it naturally cools off from the gas leaving the canister.