What am I missing here?

Have been doing mostly no boil extract, a few boils where I could set the kettle in cool water; now going all grain.

AIUI shops and catalogs are full of wort cooler copper coils that are dropped into the brew kettle and cold water run through till the desired temp is reached.

Last winter I was with some guys who put the coil in the sink, filled the sink with snow and ran the wort through the coil, regulating the temp by adjusting the speed of the wort through the coil.

I will be brewing where there is a limited water supply this fall and the ice in the sink seems to make sense; I would be interested in what I may be overlooking in this arrangement.

MAsteveINE

What you describe is sort of like comparing a immersion chiller (running water through the coil) to what is similar to a plate chiller (running wort through a coil in something cold).

Both end up using the same amount of water, but one cools the entire volume at once, and the other cools a small volume quickly. There are advantages and disadvantages to both and you should read about them to determine what is right for you.

You will need a pump to run the wort through the coil.
You will not need a pump to run tap water through the coil.
However, you can cool faster and reach a lower temperature using a sink full of snow than you can with tap water.