As more research goes into alternative energy sources, people have started looking at ways to generate more power by using waste created by other processes. One such effort is the tornado turbine we previously covered on Engineering on the Edge. Now, Panasonic has devised another such innovation that could find a use for hot water waste.
Panasonic has developed thermoelectric tubes that can generate 1.3 W of electricity by running hot water inside and cold water outside the tube. This isn’t kitchen sink style hot water, however. The water must be around 194 °F (90 °C), while the cold water needs to be at a more reasonable 50 °F (10 °C).
The system isn’t viable as a primary energy source, considering some power needs to be expended to heat the water, but it could provide a boost in power savings as a secondary source. Another possibility is plugging the tubes into geothermal sources of extremely hot water.
The tubes are a mere 10 cm long, which, according to Panasonic, makes them the most compact thermoelectric device to be found on the planet. The fairly simple design also makes the tubes one of the least intricate devices around. Most thermoelectric generators are highly complex, which makes scaling difficult.
From Panasonic’s website:
Panasonic’s thermoelectric tubes … [use] unconventional phenomena called transverse thermoelectric effect, which takes place in tilted multilayer made of thermally-resistive thermoelectric materials and thermally-conductive metals. This effect makes it possible to control heat flow and electric current independently in materials, and realizes quite simple structure without complicated electric junctions and planar substrates.
Below you’ll find a video about the tubes.