Christophe wrote:http://www.ese-solar.com/ese/produits/prod_absorbeurs.php
?
I find the ESE technology excellent. I was thinking of making tube absorbers + fins copper but I ran into the problem of welding (it is expensive soldering with tin).
That's why I found the ultrasound weld interesting.
For information I compare it to the Giordano technique which is different (copper tube + aluminum fins).
My current absorbers are Martell-Catala (fine copper pipes taken in a weaving of copper wires).