Carbon-nanotube strips harness waste heat
Where work is done there is waste heat, but research is making progress toward ways of harnessing heat so that this energy is not wasted. Devices for converting heat into mechanical energy and then into electrical energy have attracted particular interest because they produce higher voltages that can outperform Seebeck thermoelectric devices, which convert heat directly into electrical energy. However, thermal-to-mechanical energy-conversion devices have so far been large, heavy and required bulky heat baths and operating temperatures significantly above room temperature. Now, Takashi Ikuno, Tatsuo Fukano , Kazuo Higuchi and Yasuhiko Takeda have developed a simple 'bimorph' strip just millimetres in length, which converts heat into mechanical energy at temperatures below 100℃, and under a temperature difference of as little as 5℃.