Absorption refrigerator: https://en.wikipedia.org/wiki/Absorption_refrigerator https://en.wikipedia.org/wiki/Absorption_refrigerator Einstein refrigerator: htt

Absorption refrigerator: https://en.wikipedia.org/wiki/Absorption_refrigerator https://en.wikipedia.org/wiki/Absorption_refrigerator Einstein refrigerator: https://en.wikipedia.org/wiki/Einstein_refrigerator https://en.wikipedia.org/wiki/Einstein_refrigerator The principle is still used in some refrigerating devices (typically hotel mini fridges and similar small units for RV's) as there is no need of a compressor (i.e. the device is completely silent) and also in some HVAC machines.