Commentary

A Kansas state regulator denied permits to build two new coal-fired thermoelectric power plants ('thermoelectric' because they convert heat to electricity, but this type of plant does not involve Seebeck or Peltier devices) based on their carbon emmisions.   The Kansas legislature passed a bill allowing the plants to go forward, then late last week the Kansas Governor vetoed the bill and halting the project.  For now, at least.  Here's a link with the full story:

    http://www.kansascity.com/679/story/541098.html

See the 20080116 f the LA Times article "Inquisition at JPL"

Prof. Kin-ichi Uemura of Yokohama, Japan (organizer of ICT93 in Yokohama, Japan and long time contributor to thermoelectrics through his previously employer, Komatsu) informs me he has retired as a Patron of ZT Services.  Prof. Uemura's ITTJ ( Institute for Thermoelectric Technologies Japan ) was a charter sponsor of ZT Services and his support these many years has been much appreciated.   At age 85 he maintains his passion and interest in Thermoelectricity and hopes to see further development of the field.

Two remarkable articles on the thermoelectric properties of silicon nanowires (and an accompanying News and Views piece by me) appear in today's issue (Jan. 10, 2008) of Nature:

1.    Hochbaum, A. I. et al., Enhanced thermoelectric performance of rough silicon nanowires. Nature 451, 163-167 (2008).
       http://www.nature.com/nature/journal/v451/n7175/abs/nature06381.html
 2.   Boukai, A. I. et al., Silicon nanowires as efficient thermoelectric materials. Nature 451, 168-171 (2008).
       http://www.nature.com/nature/journal/v451/n7175/abs/nature06458.html
3.    Vining, C. B., Desperately seeking silicon. Nature 451, 132-133 (2008).
       http://www.nature.com/nature/journal/v451/n7175/full/451132a.html
4.   see also Editor's Summary: http://www.nature.com/nature/journal/v451/n7175/edsumm/e080110-07.html
     
Long believed useless for thermoelectric energy conversion groups working independently at Stanford and Caltech have measured ZT values near 1 for silicon nanowires at and below room temperature.  Both groups find dramatically lower thermal conductivity values and the Caltech group, working on somewhat smaller nanowires, finds a greatly enhanced Seebeck coefficient due to a 1-D phonon drag effect.

Perhaps we've come to expect thermal conductivity reduction in nanostructures but to see such a large effect in silicon is still new and interesting.  But to see a really large ZT value attributed to phonon-drag is a first and sure to stimulate further work along these lines.

I'm afraid you'll have to get the full articles either from Nature or through your library, but the above links will show you the first paragraph.

Prof. Anatychuk, Director of the Institute of Thermoelectricity,  has compiled a remarkable graphic to celebrate the New Year and Holidays.  It includes graphics of thermopiles, mostly from patents, going back to 1843.  With his permission and for your pleasure here it is:

MIT issued a press release Nov. 20, 2007 briefly describing some of Dr. Mildred Dresselhaus's thermoelectric work and drawing attention to her invited talk Monday Nov. 26, 2007 at the Fall MRS Meeting in Boston (Symposium U, Thermoelectric Power Generation, paper U2.4, 2:30pm).

At the ECT2007 I had conversation about the discovery of Bismuth Telluride as a thermoelectric material and Mr. K. Fukada of Komatsu pointed out that Maria Telkes mentions Bi₂Te₃ years before Goldsmid reported high ZT values in her brilliant 1947 paper:

 Telkes, M. (1947). "The Efficiency of Thermoelectric Generators. I." Journal of Applied Physics 18(12): 1116-1127.

Eighty Nine thermoelectricians from 21 countries gathered at Black Sea port of Odessa, Ukraine to enjoy ECT2007, the 5th European Conference on Thermoelectrics.  Attendees represented countries including Russia (17), France (12), Germany and USA (7 each), Italy, Poland, Ukraine (6 each), Japan (3) and Korea (2).   Everyone was treated to a banquet, a walking tour of Odessa and an evening excursion by boat on the Black Sea.  The center city of Odessa offered an excellent and inviting location for ECT2007.

A reader has brought to my attention the following remarkable paper:

A. Bentien, S. Johnsen, G. K. H. Madsen, B. B. Iversen, and F. Steglich, "Colossal Seebeck coefficient in strongly correlated semiconductor FeSb₂," Europhysics Letters (EPL), pp. 17008, 2007.

Aparently due to strong corellation and d- character of the bands, FeSb₂ exhibits at 12 K perhaps the largest electrical power factor ever reported:

While I was unable to attend ICT2007 I have had news from several who did. Here I shall attempt to summarize a few highlights.  As usual, all errors are my own.

243 scientists, engineers and business leaders from around the world attended ICT2007 on Jeju Island, Korea June 3-7, 2007.  By all accounts the conference was a great success.  The program (authors and titles) is available online at:

   http://www.ict2007.net/english/main.php?p=information&sp=p_schedule