I found a very interesting page about water treatment by solar means . They have a section on pasteurizing water which takes a lot less heat than boiling. Anyone have any experience with these techniques? The puddle technique sounds very interesting.

Link to Solar Water Pasteurization page.

I read some info on the web that there is a reusable temperature sensor you can put in the water to determine if it has reached the temperature for pasteurization using a solar heating system.

It is some sort of wax in a glass container, and when it liquifies you have reached the temperature required. At that point, you leave the water in the sun for a specified time (I forgot how long.) and then it is safe to drink. You can then take the temperature sensor out and it will cool down and solidify until the next time you need it. The sensor eliminates the "by guess and by golly" method of determining proper time passage.

If anyone on the forum has tried it, I would be interested in knowing if it worked or if you ended up running for the throne.

Bountyhunter

No, but I have tested this method:

http://www.sodis.ch/

and it is effective. Pete

Hey Pete that's pretty cool! Now if only I corrugated steel roof handy. <img src="/images/graemlins/grin.gif" alt="" /> I wonder if another metalic, reflective surface would be as effective.

Other metal surfaces should work as well. The main reason for the emphasis of the corrugated roofs is the common use as roofing material in rural areas and that it will hold the bottles so they do not roll. Pete

So it doesn't have anything to do with that fact that this type of metal generates more heat than many others? If this could be done with something as portable as foil that would be quite useful.

There are two aspects to why this method works. The first is the intensity of the UV rays from the sun in the middle latitudes. The second is the increase in the temperature of the water while in the bottles. The underlying metal, may have some effect on the process, as to the rate and intensity which the water is heated, but the key, to the process is the passing of UV rays though the clear plastic bottle. Pete