Researchers at Ulsan National Institute of Science and Technology (UNIST), the Korea Institute of Science and Technology (KIST), and the Korea Electrotechnology Research Institute have developed a thermoelectric paint that can generate electricity from waste heat. The paint could help power homes, vehicles and even ships.
The idea of harnessing the energy in waste heat has been picking up steam lately. I recently wrote about a technology that aims to capture the waste heat from power plant and vehicle combustion with the potential to power 11.4 million U.S. homes and small scale applications like heat exchangers in showers have become more popular.
There is good reason to focus on waste heat as an energy source -- there is a lot of it. It's estimated two-thirds of all energy produced is lost as waste heat. The new thermoelectric paint is particularly interesting because instead a device that is suited for one type of application, paint can be applied to almost any surface, allowing waste heat to be captured from many sources.
Many existing thermoelectric devices are flat and rigid, so when they're applied to objects like refrigerators or engines, there is still a lot of waste heat that escapes without being captured. Paint, on the other hand, can fully cover and envelop the surface of an object, maximizing the amount of heat that is harnessed.
The paint is made with bismuth telluride, which is often used in thermoelectric materials, and a special process was used to fuse the particles together. The paint is applied to a surface and then heated at high temperatures for 10 minutes, which increases its density and makes it more efficient at converting the heat energy into electricity. Tests show that the paint is more efficient than any other ink or paste-based thermoelectric material to date.
The researchers say that the paint would be particularly useful for capturing heat from walls and roofs during summer months. The paint could also be applied to cars and ships to help power onboard electronics and the researchers believe that the material could find its way to 3-D printed electronics and more.