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New Semiconductor Coolers
An anonymous reader writes: "A new thermoelectric material is 2.4X as efficient as
best existing materials. The new solid state heat pumps
can provide 700 watts of cooling (nearly one horsepower)
with just one square centimeter. These new materials have the
potential to replace current heat sinks, thermoelectric
generators and mechanical heat pumps.
You can also read an article in nature."
Due to the problem of fitting larger heatsinks and fans (damn loud things) onto ever smaller motherboards and chips, is it not time to re-think this idea? Would it not be possible to use this new material to pump the heat from the chip to the side of your case? The side of your case could be a very large heatsink. It would require small fins and might even improve the looks somewhat. It would not get hot due to the surface area and heat dispersion. Why use a small (relative) heatsink and excesivily (sp?) loud fan to cool the chip when you already have a large heat release area? Anyway, just a thought.
An optimist believes we live in the best world possible; a pessimist fears this is true.
It's not the temperature difference alone that determines the power, but the temperature difference times the heat flow. And I know of no theoretical limits to heat flow, although there are lots of practical problems...
Nature has the full scientific article. I don't understand most of it, but it does say "Thin-film thermoelements lead to large cooling power densities (PD)... We estimate a value of PD of 700 W cm-2 at 353 K and 585 W cm-2 at 298 K at the measured maximum cooling in superlattice devices compared to a value of 1.9 W cm-2 in the bulk device of Fig. 4a". That is, 700 watts/cm2 cooling at 70C (the max temperature for industrial-spec semiconductors), 585 at 25C (room temperature), and it's about 350 times as fast at pumping heat as the comparison thermoelectric material.
To actually use that cooling ability, you've got to somehow couple 700W/cm2 heat into one side and remove rather more heat from the other side. (Or to generate 700W power, you've got to couple more than 700W to one side and remove the waste heat from the other.) A TO-220 power transistor has an approximately 1 cm2 metal plate on the back to contact the heatsink; take a really big heatsink and really good thermal paste and really torque down the screw clamping them together, and it will handle almost 20W. 700W would fry the transistor core instantly, before the backplate even got warm. The coupling between a GHz Pentium and heatsink/Peltier refrig/fan must be better than this, but not THAT much better. Lots of luck!
By the way, anyone notice that the reporter doesn't know the difference between "efficiency" and "effectiveness".