A new flexible thermoelectric generator can wrap around pipes and other hot surfaces and convert wasted heat into electricity more efficiently, according to scientists at Penn State and the National Renewable Energy Laboratory. Penn State researchers have been working to improve the performance of thermoelectric generators — devices that can convert differences in temperature to electricity. When the devices are placed near a heat source, electrons moving from the hot side to the cold side produce an electric current.
The team has developed a new manufacturing process to produce flexible devices that offer higher power output and efficiency.
Flexible devices better fit the most attractive waste heat sources, like pipes in industrial and residential buildings and on vehicles.
In tests being conducted on a gas flue, the new device exhibited a 150% higher power density than other state-of-the-art units. A scaled-up version, just over 3-inches squared, maintained a 115% power density advantage. That version exhibited a total power output of 56.6 watts when placed on the hot surface.
The 72-couple device exhibited the highest reported output power and device power density from a single thermoelectric generator.