Done with stoves, no more

[Tom Lyons]

I have a little esbit stove to boil water, and I also make wood fires.

I have read some comments here which seem to imply that people who make wood fires are somehow "automatically" woods pigs who will also throw garbage everywhere and make all kinds of mayhem, and probably burn down 3/4 of the northern hemisphere while making coffee. And also that they are inconsiderate boors who can't put out their coals, or do other "heinous" activities.
I have seen people who use stoves be woods pigs too, and throw their crap everywhere, etc. This is not restricted to people who make a fire. Not by a long shot.
Just a heads up.

Most people who enjoy going to the woods are pretty decent about taking care of things.
The ones who are likely to leave a trail of debris are often the city dwellers or suburbanites out on a day trip or a camp-out, who really don't do this often and have no clue about most of it.

And just to show that I'm serious, I even invented a very portable solar water heater that weighed less than 12 ounces and only a foot long and rolled-up to 2" diameter, and could heat a small cup of water for tea or coffee in less than a half-hour in most cases. In winter, it took about 45 minutes. It could also pasteurize water to kill bacteria, and had a small thermometer in the cap to know the temp.
I then made one with 12-ounce water capacity for making Mountain House meals and such, but that weighed more and was about twice as long. But interestingly, it was just about the same speed for heating, so it was quite fast and it gave a more useful amount of hot water. Only problem was that it was about 2 feet long and weight a pound and a half or so, which was heavier than most here would like. But still only about 2" diameter. Just a long tube shape.
It has a roll-out reflector which wraps around the outside when transporting.

No fire needed of any kind to heat water, and in summer it could get hot enough for most purposes in about 20 minutes. It was very fast for a solar water heater.

However, people weren't interested because they would hike in the woods where there wasn't enough reliable sunshine, or they only stopped at night and left in the morning when the sun was still very low. So, it didn't catch on.
But it did very well if you put it out in the sun.
I gave about 4 of them to friends, and I still have one in my bug-out emergency bag.

[Justin Baker]

I have never heard of something like that tom. That sounds amazing. I think it could be very useful for living off the grid so you don't have to use as much fuel.

[Tom Lyons]

Justin, I have lived off the power grid for 14 years in a log home that I designed and built myself with my own two hands, and use a surface water purification and pressurization system of my own design(but using known concepts).

This portable water heater design is basically a very small version of the commercial solar water heaters seen on some building rooftops. A parabolic trough design which heats copper tubes along their axis, and are usually seen in a large array. I use a scaled-down model, with some portable design features.

Essentially, this is how you build one.
Go to Lowe's Hardware store and buy a 11" copper pressure-bulb(anti-hammer chamber) which comes closed on one end, from the plumbing supply. It is NSF safe copper plumbing. Go into the light bulb section and buy a thin polycarbonate clear protector for a fluorescent light tube. They are cheap.
Get 2 PVC plumbing end caps which fit tight over the clear protector tube. These are also NSF safe plumbing, but the caps won't touch the water anyhow.

The copper chamber is your heating reservoir. Copper is an extremely good heat conductor. The size of the copper chamber you pick will determine the water capacity of the heater. I used the 11" long one because it held 4 ounces of water which was what coffee makers consider a "cup" in a coffee machine, and it was short enough to be portable and it wasn't too heavy.
While the copper conducts heat well, it isn't dark enough color to absorb alot of heat quickly, so I sprayed the OUTSIDE ONLY with a black coating called "Thurmalox Solar Collector Coating. This is a "solar selective coating" which absorbs solar heat at 98% efficiency, but only emits IR heat out at ~20%. So it acts like a "thermal diode" and absorbs heat quicly but doesn't give much up. Perfect for what we want on the coating of our pipe.
So next, we build the housing.
The clear polycarbonate tube provides wind protection so that the wind doesn't pull heat off the copper tube during heating. And, polycarbonate has over 90% light transmission ablity, so it is one of the best plastics for that. And, it is virtually unbreakable unless you really try to break it, so it is durable for our use.
We cut this to length so that it will be about as long as the copper tube, which it will cover, leaving a small dead air space between the copper tube and the outer polycarbonate tube for insulation purposes. The PVC end caps are then put on the ends, tight enough to hold the copper tube rigidly in the middle. If you need to glue the copper tube at the bottom to hold it, that's ok. Just make sure that the open top of the copper tube extends thru a hole you drilled for it in the middle of the top PVC cap.
Buy a rubber stopper that fits, and drill a small hole in the middle, and put a meat thermometer with metal probe thru the rubber stopper. This allows temp monitoring of the actual water temp inside, and the rubber stopper will pop out if any pressure builds up inside, so it's a safety valve.This completes the basic structure.
For the "parabolic trough reflector", we use a parabolic "approximation", which we get by cutting a piece of aluminum roof flashing to a size that will cover our heater when we wrap it around it as a cover. Then we drill holes in the back of the PVC caps and the sheet aluminum to attach it to the PVC caps so it is held to the outer body of the water heater in the middle of the reflector, so that the reflector is equal and symmetrical on both sides of the heater body. We polish the aluminum up shiny, and curl it by hand, so that when it is laying there on its own, it has a sort of parabolic curl to it. You can work with this by shining a light at it, and seeing how well the light is focused onto the tube longitudinally by the reflector. When you are satisfied with that, you can just wrap the aluminum reflector around the body of the heater, and put a couple large rubber bands or o-rings around it to hold it, and it is rolled for transport, and protected by the outer covering of the aluminum reflector curled around it.
This size model weighed 10.2 ounces total weight for me, without the thermometer. The thermometer adds weight and isn't necessary unless you want to monitor temp for water purification by pasteurization process. This small model only holds about 4+ ounces of water. It's very small capacity.
Doesn't cost much to make one of these, and you could do it in a fairly short time.

I timed the heating, and in the first 10 minutes after you put it in the sun with water in it, the temps climb about 4 degrees per minute. So, it will go from room temp water to about as hot as your hot water tap(125*F) in about 15 minutes, and then it begins to slow down. A Mr. Coffee machine puts out coffee into the pot at 140*F, even though it boils to percolate, it ends up at 140 when it gets to the pot. So, that is hot as a cup of coffee that you pour out of your coffee machine. I measured the temp. My heater will give that temp in about 20 minutes or so. To pasteurize for bacterial purification, you need to hit 160+degrees, which will take you at least 45 minutes or more, depending on how warm/cold the weather is outside. You monitor this with the thermometer in the cap, and you need to do several minutes above this temp to pasteurize. Boiling is NOT needed to purify water, but it is used as an easy to see indicator that the water is over the necessary 160*F for pasteurizing bacteria.
I did all this at about 34 degrees N Latitude. Higher latitudes will take longer, and lower latitudes nearer the equator will take less time. Aim the device directly at the sun for best results. I lean mine against a rock or my pack to get the right angle aimed at the sun.

So, there you have it. It is a very small capacity(4 oz) portable solar water heater under 3/4 of a pound carry weight, about a foot long and about 2" diameter O.D., and it fits into just about any backpack, and it's very fast heating for a solar water heater device. Perhaps the fastest known. I have never seen figures for any other small solar water heater that were as fast. Most are WAY slower.

[Nick Gatel]

Don said,

"Time for a different opinion. When I started backpacking, we always cooked on open fires – there was no other option. I first started using stoves on winter high altitude climbs, and eventually carried a liquid stove when in rainy conditions.

Over the years, my use of a stove has become more and more routine. Cooking is quicker, the chance of starting a wildfire is lessened considerably, and the weight is inconsequential, especially considering the convenience of canister or alcohol stoves.

To each his own, I guess. But open campfires, other than emergencies, are a giant step backwards. And, indeed, I do carry the tinder and means of ignition so that I can do an open fire if required."

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Agree. When I discovered stoves I switched because fire blackened pots were hard to clean and got everything dirty. Plus stoves were quicker and easier to use. I never build a campfire, it cuts you off from the environment. Those are my reasons.

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