"Thermoelectrics Make a Comeback" was the title of a recent C&EN article (June 20, 20110, pages 33-35). We previously reported how nanotechnology is providing new thermoelectric technology which could be used for solar. This latest C&EN article confirmed (1) the vital role of nanotechnology in developing thermoelectrics, and (2) the applicability of thermoelectrics to cleantech. The gist of the article is that, after being dormant for decades, thermoelectric science and technology is becoming much more widely recognized as a topic of important interest.
Nanotechnology is woven throughout the article. For example, one of the key events which helped to reawaken the thermoelectric field was a theoretical paper in the 1990's (MIT Professor Mildred Dresselhaus) in which the critical ZT thermoelectric property was shown to increase with thinner and thinner films. Then the concept was applied to one dimensional nanowires. The concept of nanoscale confinement was born, and verifying experiments were carried out. Discussion is found in the article about nanoscale materials, nanowires, nanometer-sized crystallites, and the like.
The Department of Energy is sponsoring a multi-year project funded by the DOE, according to the article. General Motors is developing prototype devices that use automobile exhaust heat to produce electricity for onboard use. Thermoelectrics are needed which can work at high temperatures.
Patent filings are also apparently rapidly increasing in the thermoelectric field. Since 2001, 1,865 US patent applications have published which mention thermoelectric in the abstract. In those ten years, the annual number has risen steadily - and first doubled and has now almost tripled (data are below under read more). If 2011 continues in the second half as in the first half, a record number of patent applications will publish in 2011, clearing 300 per year for the first time. In addition, 31 of these are classified under 977 nanotechnology, with most of those being in the past three years.
Annual U.S. Patent Publications Reciting "thermoelectric" in the Abstract
2011 - 155 patent publications (projects to 310 for the year, 2011)
2010 - 278
2009 - 230
2008 - 213
2007 - 202
2006 - 211
2005 - 182
2004 - 135
2003 - 126
2002 - 110
2001 - 23 (incomplete year as US patent publication just started)