A few good points are brought up here.
They are basically a peltier junction idea that has a thermal seperator between them
to tame the losses that occur with current peltier devices reducing their efficiency dramatically.
The electrons must now traverse the junction through a nano layer via thermionic emission instead.
So the side your trying to keep cold by removing energy from it,
requires far less maintained energy transfer to keep it so.
Or the side your trying to introduce energy to instead, to recycle said energy,
wastes far less of it via thermal conduction to the cooler side.
Nice idea really...
Think about the curent solar panel color and the intense heat going to waste from them,
this could salvage that waste energy if what they report on the website is true.
Either way, we are surrounded with potential thermal differences in many forms daily,
but the thermal loss across a standard Peltier device tends to want to destroy that potential difference.
Thought about in the opposite direction,
Peltiers have a basic plotted curve of maximum potential difference from one side of the junction to the other
due to this same thermal coupling issue inherent in the Peltier's design.
By breaking that link like this,
I would suspect that absurd potential differences in temperature could be achieved with an applied voltage/current.
I have written them directly about a few points not covered,
like are the two working surfaces also electrically conductive as well as thermally conductive.
20-Amps is wonderful (per square centimemter),
but at a single junction's voltage of about a half a volt nominal,
it will need to be arrayed in series-connected block arrays
to be of any practical application value with todays electronic and electromotive devices.
Currently, insulators need to be used with peltier's to eliminate them from shorting out
when mounted on conductive surfaces like aluminum heatsink material and connected in series arrays.
That adds to the loss of using them to an additional large degree too.
Basic Overview:
http://www.powerchips.gi/technology/overview.shtml