"ENERGY: Heat generates electricity"

Acoustically coupled transducers can directly generate electricity from heat, researchers reported on June 8 during the annual meeting of the Acoustical Society of America here. The team's so-called thermoacoustic prime mover consists of back-to-back heat exchangers with an intervening stack of materials tuned to a resonant acoustic frequency. When heat goes in, a resonant sound is generated and acoustically coupled to a piezoelectric transducer, which converts the sound into electricity.
Text: http://www.eetimes.com/showArticle.jhtml?articleID=199903412