All machines and appliances that use energy produce waste heat, heat that costs energy to produce, but evaporates into nothing. Thermoelectric materials can help in that aspect, as they turn warmth into energy. However, the majority of the thermoelectric devices are flat and rigid, which, if fixed to a curved surface, still accounts to heat loss. Researchers at Ulsan National Institute of Science and Technology, the Korea Institute of Science and Technology, and the Korea Electrotechnology Research Institute have come with a solution. They developed a thermoelectric paint that can be applied to nearly any surface.

Paint is much more than just a nice colour on the wall nowadays. Earlier, we reported on paint that can change colour and paint with solar cells. This thermoelectric paint fits right in that ally of innovative and smart paints.

Thermoelectric paint contains bismuth telluride (Bi2Te3), a type of particle that most types of conventional thermoelectric devices use. After sintering for 10 minutes at 450 degrees Celsius (842 degrees Fahrenheit), the painted layers form a uniform film of about 50 micrometres thick. Tests showed that the devices painted with the thermoelectric paint exhibit a high output power density that are competitive with conventional thermoelectric materials and better than all thermoelectric devices based on inks and pastes.

The paint can be applied to almost any surface, which included walls and roofs. Especially during hot summer months, an enormous amount of heat can be captured and turned into energy, which is good for our wallet and our planet.

Photos: Stockphotos / Pat Freling of Paint Strategies