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 bul