The 27^th International Conference on Thermoelectrics, ICT2008, drew over 340 thermoelectric specialists from about 27 countries to Corvallis, Oregon USA Aug. 3-7, 2008.  The conference was held on the beautiful Oregon State University campus in Corvallis.   Participants and accompanying persons enjoyed dinner at a local winery one night and an outdoor banquet on the University of Oregon campus in Eugene, a short drive away.  The conference ran exceptionally smoothly thanks to the efforts of conference Chair David Johnson and, of course, all the hard work by the local organizing committee.

I counted about 60 oral presenations and about 153 posters in the conference program, which is available online.   Obviously I cannot do justice here to such an extensive program, but the following highlights caught my eye.

Lon Bell of BSST discussed "Addressing the Challenges of Commercializing New Thermoelectric Materials".  He points out that no new TE material is yet available that improves efficiency at the system level but that a ZT~1.8 could produce sales of about US$2.8B in five years, compared to about US$30M today for ZT~0.7.  He has challenged the TE R&D community to re-organize to produce a faster R&D process.

Cahill of the University of Illinois presented 'Thermoelectric Properties of nanoscale V2-VI2 “soft superlattices”'.  Laminates are now known that have thermal conductivity values below what we once called the minimum thermal conductivity.  It seems we should drop the term 'minimum', since it isn't, and perhaps use the term 'amorphous limit' instead.  The key to really low values, he says, may be the 'anisotropic glass'.

Sang Mock Lee of Samsung discussed "Highly efficient thermoelectric module designs for micro-cooling and green IT applications".  He estimates a US$26B market for cooling and US$16B for power generation and suggests thermoelectrics needs a roadmap for development and commercialization.

Harold Böttner of the Fraunhofer Institute spoke on "Thermoelectrics for high temperature differences may complement renewable energies:  A survey about state-of-the-art of so-called high temperature thermoelectric materials".  He showed a BMW with a 750 W TE generator (not a proposal, a real car with a working TE generator) and indicated a target of bringing these to market in 2011.  He also estimates that the total world supply of tellurium is not nearly enough to put TE generators in all cars, highlighting the need for high ZT materials free of tellurium.

P. van der Sluis of Philips gave a nice presentation and live demonstration of "Thermoelectricity applied in woodstoves for residential cooking".  In this concept an inexpensive TE device is incorporated into a small wood-fired stove to produce just enough power to drive a fan.  The fan improves the fuel efficiency of the stove.  Large numbers of people today rely on woodstoves for cooking, placing a huge burden on local wood supplies.  Philips hopes to produce these stoves cheaply enough, based either on Bi₂Te₃ or possibly Type E thermocouples,  to sell directly to the users.

Jeff Sharp of Marlow Industries discussed "An Industry Perspective on Thermoelectric Power Generation Materials".  Sharp estimates TE modules must cost US$4/Watt to enter the markets they've identified.  Tellurium comes mostly from copper ores and is one of the most rare elements.  Today, tellurium costs about $300/kg, but to meet the US$4/Watt target tellurium must cost less than US$150-200/kg.  Sharp suggests tellurium-based TE materials have become impractical for waste heat, and the situation would only get worse if demand for thermoelectrics increases.

Obviously, there were many more excellent presentations.