Which do you suppose is more efficient?

[mlydon]

In an icebox loaded with ice, do you suppose you lose less cold by keeping the water drained, thus minimizing conductivity to the walls of the box, or to keep the ice water in the box, thus squeezing every last bit of cooling power from your load of ice?

Matt

[daddle]

Always drain the water. But don't leave the plug open. The liquid's conduction to the walls is the problem. And liquid water is 40 times less effective than ice at cooling.

[Auzzee]

Yup, drain the water and close the drain cock afterwards. For super efficiency on a slightly longer journey, buy a housebrick sized block of dry ice, wrap it in newspaper and plonk it on top of the goodies in the ice box. It will make your ordinary ice last for a couple of weeks.

[MysticGringo]

We used to drain it constantly... then we stopped and kept the water. It's still cold, so acts as a cold thermal mass and regulates the temperature. Beer goes at the bottom and eventually is covered by the water. I can only get 2 beers before my hand is cold enough to cause pain. Keep the water.

Once the ice has completely melted... drain.

[mausgras]

Originally Posted by Auzzee

Yup, drain the water and close the drain cock afterwards. For super efficiency on a slightly longer journey, buy a housebrick sized block of dry ice, wrap it in newspaper and plonk it on top of the goodies in the ice box. It will make your ordinary ice last for a couple of weeks.

I often wonder why we don't still use dry ice or even liquid nitrogen . It can be stored very efficiently and if used in a specially designed chest can be stored for ages.

[zeehag]

make sure there is a loop in the outflow hose from ice box. that will keep cold into ice box. let water come out--standing in water makes ice melt--

[Rakuflames]

Originally Posted by mausgras

I often wonder why we don't still use dry ice or even liquid nitrogen . It can be stored very efficiently and if used in a specially designed chest can be stored for ages.

The problem I've had with dry ice, even in the very large ice box built into the boat, is that it's too good. Food freezes. What I do with it is use it freeze bags of ice into blocks. Then I put the dry ice in a cooler if there's any lfet, but I'm just not geared to frozen food any longer. Since I live on the boat, I can't really cook ahead and freeze. For those who can, by timing their food right and using dry ice, their food can last a much longer time.

[tamicatana]

We put dry ice, in plastic bag, at bottom of box. Next, water ice over that, then food. Ice lasts much longer.

[mausgras]

re dry ice, To answer my own question I have just thought of a potential good reason not to use dry ice.

It is heavier than air and when it evaporates would accumulate in the bottom of the boat. It is not poisonous but does not support life either. There is a danger of suffocation in a poorly ventilated saloon or a boat closed up during heavy weather.

But every problem has a solution. Perhaps storage in a lazarette in the cockpit and somesort of coolth exchanger.

I do not have the skills but I wonder how the energy budget and carbon footprint would come out for industrial scale production of dry ice to stock ice boxes as compared to energy/CO2 balance for a million refrigerators working with electric motors.

[Swift Drift]

To the OP's original question:
I try and keep water out of my ice box. I'm no scientist, but thinking through it logically convinced me that water is not a good thing when trying to extend the life of my ice. I thought about a glass of ice water.... The ice melts much faster when there is water in the glass than when not....assuming your not in blistering heat. I stand to be corrected and would be intrigued if someone has a nerdier and well supported explanation to the contrary.
Additionally, I don't like to have a sloppy wet icebox.

[Cheechako]

I have found in a cooler for camping etc, that the ice seems to keep longer if the water is left in there. They do say a fridge cools better if it's full-ish as opposed to mostly air. Probably because when you open the door/lid, much of the cold air is replaced with warm. if more volume is taken up by near freezing water.. not so much warm enters.....
Good example on a glass of icewater though... I guess the question is: In an hour or so, the glass of ice only (drain in bottom) will have only air in it. The glass of ice water will have only water in it. Which will have the coldest environment?

[RainDog]

FWIW - the cooler companies (coleman, igloo, etc.) say the ice will last longer if you do not drain the water. They do provide any evidence for this claim.

[Swift Drift]

In the name of full disclosure, I would like to pass on an error with my glass full of ice experiment:

Generally I drink my drinks at a higher rate than would be allowable to classify this example as scientific..... Back to the drawing board I guess....

[rtbates]

Originally Posted by zeehag

make sure there is a loop in the outflow hose from ice box. that will keep cold into ice box. let water come out--standing in water makes ice melt--

DITTO. I installed a small 'J' trap in our drain and keep the ice on a tray above the water.

[ddfishon]

This is from Yeti's website:

Once the cooler is in use, we recommend that you do not empty the cold water. The water in the cooler will be almost as cold as the ice and will help insulate the remaining ice.