Not a rocket but cool none the less.

Chad Ellis wrote:http://www.youtube.com/watch?v=P_EKTLnKjfs

Umm.. no ex-spert here? But I believe it is about “No Smoke & No Heat” out of the exhaust?
That Video doesn’t show enough about what is going on in it?

I built an incinerator many years ago, it still exists, I get no smoke out of it too. Sometimes though, you can see the flames coming out of the pipe. Dan has a point.

Ok, now I have seen it in person. Traditional wood stove outside. Heat exchanger on top. It convects cool air in on the low side and hot air out on the high side. He plans on adding a solar charged 12v fan to force more air through the heat exchanger. Not the most efficient on the wood but does a good job keeping the plastic on the greenhouse from melting due to a wood stove inside.