I came across this and it sounds like an interesting technique.

http://survivaltactic.com/
Making water in winter. 7/31/2007
Roll up a 48oz NALGENE Cantene and stuff it in a survival kit. When out in snow country, fix a neck strap to the Cantene, wear it under your parka and refill it with a little bit of snow each time you drink. The small amount of snow will melt while not making the rest of the water too cold, and you'll always have fresh water. Drink water often: if your tongue hits your knees when you walk, you haven't been drinking enough.

Anyone tried it?

I've been doing something similar for many years, especially on day hikes when I don't carry a stove. It works even better if you start off with a hot drink in an insulated flask or a water bottle with an insulating cover. Coffee is not a good idea unless you like lukewarm weak coffee! Hot fruit juice or similar (I like ginger cordial)is excellent as it's still tasty even when cold.

When camping collecting snow in a black stuffsack or pack liner and leaving it in the sun is a good way to produce water without using fuel.

Good find - that sounds like info ripe for the Wiki.

I think placing it under your jacket while walking (when you probably have an excess of body heat) is likely even better than the other method I've seen -filling up a canteen with snow and sleeping with it in your sleeping bag. The latter sounds like a great big heat thief when you're probably at your coldest, but I haven't tried it so I may be overestimating the effect.

Thanks Chris. That is encouraging.

>I think placing it under your jacket while walking (when you probably have an excess of body heat) is likely even better than the other method I've seen -filling up a canteen with snow and sleeping with it in your sleeping bag. The latter sounds like a great big heat thief when you're probably at your coldest, but I haven't tried it so I may be overestimating the effect.

Certainly. Infact the opposite should be done i.e. sleep with your canteen filled with hot water.

"When camping collecting snow in a black stuffsack or pack liner and leaving it in the sun is a good way to produce water without using fuel."

I tried this several times and never got it to work at all. I used a black garbage bag, filled it with snow and left it out in the sun all afternoon. When I returned, I had a big bag of snow. My guess was that it was too cold for this technique...have you done this successfully? What were the weather conditions?

I've done it successfully - meaning mostly water in the bag- and semi-successfully - meaning wet rather than dry snow in the bag. Success was on ski tours in the High Sierra in April with the bag left in hot sun all day sheltered from any wind. Semi-success was in cold, windy conditions in various places where the sun wasn't hot enough to melt the sun. However the fuel saved due to having wet rather than dry snow to melt still made it worthwhile.

Some people suggest using a clear plastic bag over the black plastic bag. Also, put the bag on an insulated surface like a stove pad.

I've tried melting snow in just a black plastic bag here in the Coast Mtns in winter - I got wet snow that was a lot quicker to melt over the MSR than chunks of snow grabbed from nearby. I did it more to save time melting snow than to save fuel.

Insulating the bag from the snow is definitely a good idea. I should have mentioned that. I usually put the bag on a foam pad. Once I hung it from a branch.

Steve,
It worked like a charm for our crew at Plummer Hut on a climb of Waddington some years ago. Weather was sunny and cool to warmish(~50 degrees) by mid afternoon, but mostly not windy. We set the bag on a platform of exposed rock, not on snow, and started with wet snow. We didn't try it up higher when we were totally on snow at around 10,000', so I can't vouch for how universally applicable the technique is. I've also seen people use the technique in early spring conditions in the Cascades. I think the trick is to insulate the bag from the underlying snow, flatten it out to provide maximum surface area facing the sun, and keep it out of the wind.

We've used this trick as well - even when we have stoves.

Load snow into a black plastic bag, spread it out into a reasonably thin layer, and put it out in the sun; you'll have water and slush in a matter of hours, and even if you have a stove, it saves quite a bit of fuel.

(Also makes it more convenient to have the slushy water at hand to add to the pot.)

Well, you guys have convinced me to give it another try. I definitely never tried to insulate it from the ground (which is usually snow) or from wind...I just figured that because the temps were so low, the snow just wouldn't melt on it's own. We'll see...thanks guys!