DIY: Build a solar water heater for under $5

from Lifehacker by Adam Pash

DIY site Instructables details how to build a solar thermal water heater on the cheap using parts from a recycled refrigerator grill and a few other bits and pieces. So how well does it work?

I let this guy run for a couple of hours one hot sunny day and heated up a five gallon bucket of cold water (measured at 70 degrees F) to over 110 degrees F. The temp that day was about 76 degrees F. If the water is allowed to sit in the panel for several minutes and then forced out (by blowing in one of the hoses) the water was measure at 170 degrees F.

The actual device isn't currently the most practical way to heat water for an entire home (it's more of a prototype), but it's a very cool idea. As for the price, you're going to have to do some salvaging to hit the under $5 mark, but even if you don't the materials should be rather cheap.

Solar Thermal Water Heater For Less Than Five Dollars [Instructables]