Take a browse around this website, especially push the red button.
http://www.hi-z.com/...did you get the "first impression" that I did -- that this is a bunch of bodgers slapping together what is most likely a rebrand of someone else's thermoelectric modules?
So imagine my surprise when I found a full PDF of a slideshow for one of their papers in the materials for a national 2005 conference on thermoeletrics:
http://www.eere.energy.gov/vehiclesandfuels/pdfs/deer_2005/session6/2005_deer_krommenhoek.pdfSpecial attention to pages 11 and 28.
So much for garage bodgers... these guys are actually pushing the state of the art.
So what's the signifigance of a high-efficiency, low cost peltier thermoelectric? Well they have a niche -- thermophotovoltaics are very efficient but require high temperatures. Thermoelectrics can handle the low-end -- places where there is an abundant supply of not-quite-so-high-temperature heat. That's exhaust pipes, for example. Even with only 10-20% efficiency, if the heat is easy to collect the economy of converting it will likely be there.
Current thermoelectrics are about $8/W from the best online source I can find. If the raw materials cost translates in a signifigant way to post-production cost, these would be one tenth the cost of Hi-Z's modules (also in the $8/W ballpark) that would be near that magic sweet spot of cost-competitivity with fossil generation equipment.
FWIW.