Panasonic Corp started to test the power generation capability of its "thermoelectric tube" at the Northeastern Clean Center, a waste disposal plant in the Sakyo Ward of Kyoto City.
The thermoelectric tube is made by alternately stacking a thermoelectric conversion material having a low thermal conductivity and a metal having a high thermal conductivity in a diagonal direction to form a tube-like shape. Electricity can be generated by, for example, flowing hot water in the tube to create a temperature difference between the inside and outside of the tube.
With a simple, compact thermoelectric unit using the tube, it becomes possible to generate electricity by using a low-temperature (200°C or lower) heat source such as a heated water discharge in a plant. With the unit, an electric current is extracted in a direction perpendicular to the heat flow.
In the test, Panasonic prepares hot water whose temperature is about 90°C by using low-temperature steam, which is generated by incinerating waste in the plant but was not utilized in the past. Then, the company flows the hot water inside a prototype of the thermoelectric tube and cooling water (about 10°C), which is used in the plant, outside the tube.
Panasonic generates electricity by creating a temperature difference between the inside and outside of the tube and tests the power generation capacity of the tube. It aims to achieve a capacity of 400W/m3 or higher.