Scientists at the University of Limerick (Ireland) and the University of Valencia (Spain) have succeeded in generating environmentally friendly energy from body heat. Under the leadership of Muhammad Muddasar, they are continuing the work of a team from the Technical University of Darmstadt (Germany).
The research uses thermoelectric generators (TEGs) made of semiconductor elements, which can generate electricity with the help of small temperature differences. Previously, cadmium, lead or mercury were used for this purpose. Muddasar and his team have now developed a sustainable variant in which the semiconductors are based on the wood waste material lignin. These semiconductors consist of tiny channels that are filled with a highly concentrated salt solution. If one side of the TEGs is then exposed to a heat source, the negatively charged ions move towards the heat source, while the positively charged ions in the solution migrate to the cooler side. This generates an electric voltage.
TEGs made from lignin are not only suitable for portable electronic devices, but could also become interesting for converting industrial waste heat into electricity.