Micro Heat Exchanger/Heat Pump
Source: Pacific Northwest Laboratory
Date: 8/1/95    Record No.: 10189
Contact: Kevin Drost, 509-375-2017

Micro Heat Exchanger/Heat Pump
PNL is developing a miniaturized vapor-compression cycle heat pump smaller than a dime that could be fabricated by the hundreds in thin layers on a single sheet. Such sheets could be incorporated into walls of buildings, replacing conventional HVAC.

They've had success with the evaporator and condenser components, attaining heat transfer rates of 100 watts/cm2. The compressor is more of a challenge. Work is proceeding on two fronts, one a chemical absorption cycle, driven by heat, and the other a miniature electromechanical pump, which is showing earlier promise. Without the compressor, the evaporator and condenser could be configured as a thermo siphon for cooling electronics.

This work is definitely in the "potentially revolutionary" category, though actual commercial applications are years away. Possible uses: Controlling chemical processing very precisely, which for example could make it possible to make a very high performance reformer for use with fuel cells or at the wellhead. Another application: cooling for protective clothing for use in hazardous environments.