How can thermoelectric generators be made more efficient?
Thermoelectric generators (TEGs) are a promising new way to produce electric energy directly from heat. But there is one remaining problem: the low efficiency.
Today, TEGs can have efficiencies of up to 10%. The biggest challenge here is that we want the TEGs to have high electrical conductivity but low thermal conductivity. As you can see in the screenshot of the NakedScientists' video on TEGs, the used materials conduct charge carriers like electrons - which is what we need to get an electrical voltage at the ends of the material. But the materials also conduct heat - and that's not so good, because this thermal conductivity leads to a decrease of the temperature difference between the two ends and therefore decreases the efficiency of the TEG.
So the challenge is to reduce the thermal conductivity. One way to do this is to bring in atomic interfaces that prevent the heat from moving around. Scientists from all over the world are working on new material combinations with sophisticated nanostructures to improve the properties of thermoelectric generators. With EMIL providing new methods to investigate such materials, we are looking forward to the future of TEGs and with them a more efficient way to produce and use energy!