Most efficient way to cool a glass of water

[jenny tales]

im doing an investigation into what is the most efficient way to cool a glass of water. so far i am looking at:
-Refrigeration/ Freezing
-Adding liquid coolants:
-Antifreeze
-Distilled water
-mineral oils

any more ideas?

 

[russ_watters]

Efficient or fast? They are not the same thing. And you'll need to be more specific about what you are going to do. Ie, the most efficient way to cool a glass of water from boiling to room temp in a room is by letting it cool on its own: you add no additional heat to the room, as you would if you used any sort of active cooling.

 

[Danger]

Yeah... for fast, I'd consider dropping it into a vat of liquid nitrogen. Given the energy expended in order to liquify the nitrogen in the first place, however, it's hardly efficient.