I like this concept. I may not be totally understanding how it works. If I'm reading it right, it's just a solar still using hot rocks instead of the sun. I think that's a very good idea.
I'm going to go add about a 4x4 piece of visquine and some surgical tbing to my PSK right now.
Has anyone tried a still this way, and if so, any tips on making them work efficiently?
Luke