Worlds best cool box for £35

[Dutch01527]

I do not have room for a fridge and have struggled to keep food / drinks cold using camping type cool box’s. The expensive brand name versions are better but still do not deliver the 3 days they advertise in my experience.

I stumbled across a army surplus Norwegian Army designed food container used to keep food hot for days in the Artic. Not the prettiest thing and not massive at 18 litres but it really works. Pre cooled it for a few days with a big bottle of frozen water. Loaded it with a bag of ice, beer, milk, bacon ect last Friday morning. Still had ice cubes and everything was cold ( I mean cold not just slightly cool) on Monday when I got home. I am thinking of buying a second one with food container inserts that I could fill with hot food. Curry / rice and and a cold beer anytime I want with no effort, a sailors dream.

Link below, no connection with the seller, just a happy customer


https://www.surplusandoutdoors.com/...MIwLm17N3P5AIVxbHtCh2YgAfMEAQYAyABEgK-A_D_BwE

 

[ShinyShoe]

Interesting.

I suspect it will also be more robust than most plastic cr@p.

I use some huge HDPE boxes at work and while the box is solid enough to hit with a truck at 70mph, you'd want to make sure you didn't nudge the catches when you put it on the ground.

How often did you open it - that does make a big difference to how well this stuff works.

 

[Dutch01527]

It is very strong, suspect that you could hit it with a lump hammer with no damage.

Opened maybe 5-6 times a day. I tried to limit how long it was open by closing the lid as quickly as possible.

 

[lw395]

What the makers say:
Filled with 10kg crushed ice:
Ambient temperature +39°C. After 24 hours there remained 3.42 kg ice
5 Ambient temperature +21°C. After 24 hours there remained 5.54 kg ice

http://www.hawkmoor.com/detail.php?p=36

So let's guess a UK hot summer day might be 18 in a yacht at night and 25 during the day?
So the 21degC is good rough average.
That's 4.5kg of ice melted. 334J/g latent heat of melting ice. 1.5 MJ.
I make that about 17W
Which is 'good' rather than perhaps 'worlds best'.
But ou could build it into a locker with more insulation perhaps?

 

[Dutch01527]

What the makers say:
Filled with 10kg crushed ice:
Ambient temperature +39°C. After 24 hours there remained 3.42 kg ice
5 Ambient temperature +21°C. After 24 hours there remained 5.54 kg ice

http://www..com/detail.php?p=36

So let's guess a UK hot summer day might be 18 in a yacht at night and 25 during the day?
So the 21degC is good rough average.
That's 4.5kg of ice melted. 334J/g latent heat of melting ice. 1.5 MJ.
I make that about 17W
Which is 'good' rather than perhaps 'worlds best'.
But ou could build it into a locker with more insulation perhaps?

Mine was made by Dyno Kongsvinger A.S. Of Norway. No idea if the spec is the same as the British one referred to above. Not sure that crushed ice is a reasonable real world test. I had a 1.5 L bottle of frozen water and bag of ice cubes. It still had ice cubes left after 3 days and the bottle was half defrosted. That will do for me for £35.

 

[William_H]

Just as a matter of interest here are some offerings in Oz. Insulated cool boxes are part of every family. I reckon I could count about 10 different sorts around my house. Including cool bags for frozen shopping. A cool box is all about insulation. I reckon a standard largish cool box with ice in another box inside or in an insulated bag would work best for long term ice survival. https://www.bcf.com.au/camping/fridges-and-coolers/iceboxes-and-soft-coolers ol'will

 

[lw395]

Mine was made by Dyno Kongsvinger A.S. Of Norway. No idea if the spec is the same as the British one referred to above. Not sure that crushed ice is a reasonable real world test. I had a 1.5 L bottle of frozen water and bag of ice cubes. It still had ice cubes left after 3 days and the bottle was half defrosted. That will do for me for £35.

The spec is the same, It's a Nato stock number. It may outperform its spec. Or not.
If the local ambient is lower, it will defrost less.

 

[LittleSister]

So let's guess a UK hot summer day might be 18 in a yacht at night and 25 during the day?
So the 21degC is good rough average.
That's 4.5kg of ice melted. 334J/g latent heat of melting ice. 1.5 MJ.
I make that about 17W
Which is 'good' rather than perhaps 'worlds best'.
But ou could build it into a locker with more insulation perhaps?

Won't it depend on how cold the ice was to start with?

 

[JumbleDuck]

What the makers say:
Filled with 10kg crushed ice:
Ambient temperature +39°C. After 24 hours there remained 3.42 kg ice
5 Ambient temperature +21°C. After 24 hours there remained 5.54 kg ice

The built-in coolbox on my boat melts 2kg per day in hot summer weather and 1kg per day when I'd put on a jumper.

 

[lw395]

Won't it depend on how cold the ice was to start with?

Not ever so much, becuase the latent heat of ice at334J/g is much larger than the heat capacity of about 2J/g/K times say 10 degrees.
I.e. if the ice starts off at -15degC, it only makes a 10% difference.

One can complicate things by using 'freezer blocks' which freeze at a lower temperature and may have a greater latent heat.