Wherever there’s enough of a temperature gradient between two surfaces, thermoelectric materials can be used to generate an electric current. If a coat were made with thermoelectric felt, for instance, a current could be generated by exploiting the difference between the wearer’s body heat and the cold outdoor air. Now, scientists have developed an inexpensive new type of thermoelectric material, that could make the technology more commercially viable.
The material was developed by a team from Michigan State University, led by Prof. Donald Morelli. Although synthetic, its composition is based on that of a family of naturally-occurring and vastly-abundant minerals known as tetrahedrites. That composition has been tweaked just slightly, to make the finished product thermoelectric.
The production process involves grinding “very common materials” into a powder, then using a combination of heat and pressure to compress them into the sizes needed.
Although some other materials are more efficient at converting temperature gradients into electricity, Morelli maintains that many of those are unfit for practical use because their components are rare or toxic, or they’re too expensive to synthesize.
“Typically you’d mine minerals, purify them into individual elements, and then recombine those elements into new compounds that you anticipate will have good thermoelectric properties,” he said. “But that process costs a lot of money and takes a lot of time. Our method bypasses much of that.”
It is hoped that the new material could be used to cost-effectively harvest electricity from sources such as vehicle exhaust pipes, industrial power plants, and home furnaces.
A paper on the research was recently published in the journal Advanced Energy Materials.
Source: Michigan State University
BUT
Don't start thinking about using these in places where there is an excess of energy that needs to be disposed of... putting these on processors to make use of the heat differential there, would likely destroy the processor since the removal of the excessive heat-energy needs to be accelerated, not slowed (to do work creating electrical energy).
Places where there is an excess of energy that needs to be disposed of is where we should be thinking of placing them. Granted it would take adding a larger radiating surface but in exchange for capital cost you get fuel cost free electricity.
If that can be done economically, that will be a seriously valuable breakthrough.
Of course, reversed, it will be usable for the construction of refrigeration plants with no moving parts on a much larger scale than is commonly available for the TEC-operated drinks coolers for use in cars and campers, and if the temperature can be lowered sufficiently, perhaps even superconducting power transmission lines.
Of course, the patent royalties will probably keep the price up to the point where I still can't justify it.....but 20 years from now, watch out! :)
IBM had a new fab created peltier in the works a while ago I heard about on NPR. No word since, any one got anything on that? I vaguely remember in the high teens for efficiency.