Stumbled across this today. Neat concept and the website has a few other good projects

Be warned....the website is feeling the digg effect right now and may be slow loading or unreachable.

Interesting. Who knows, it might actually work.

I wonder if there could be any residue from the coolant used in the refer left in the tubing, and if so, what effect it might have when you drink the water? Or is this thing for washing only???

Interesting, thanks for the link.

The one thing that is invariably missing from all these cute "alternative energy" projects is any economic analysis.

He says he heated five gallons of water from 70F to 110F in "a couple of hours". I calculated that it takes about 415kJ of energy to do that. 415kJ is about 0.12 kHh or about 1 cent worth of electricity.

Just think, if he repeats this twice a day, in just about 250 sunny days from now he'll have broken even on his $5 investment. Not counting the cost ductape for maintenance, of course.

The foil reflector on the solar heater is a bad idea. Better to coat the back of it with a dark, light absorbing material. Otherwise you're just reflecting light back outside your collector.

Also, thseng? this is a 5 dollar water heater. Electricity does not boil water. It requires an investment in a boiler or heater. How much did the boiler in your house cost when it was installed? Bet you 5 bucks it cost more than this solar heater. And if you're going to compare the cost effectiveness of a solar heater to an electric heater, as you pointed out, the electricity for this will cost you one cent, while solar energy is free. So financially we have:

Solar heater: initial investment of heater=$5, cost of energy=$0
Electric(or gas): initial investment > $5, cost of energy > $0

Also, there are reasons to do things besides financial justification. A solar heater heater has no dependence on power lines, or any power source besides the sun. This means it will work with the power off, whether from a blackout or from not paying the power bill. That independence is worth something to me.

His unit really looks too small to be very useful.

But if you were to look through some of the Mother Earth News archive articles...
http://www.motherearthnews.com/article-categories.aspx
...there seems to be some very useful-looking info there (esp some of the older articles).

Sue