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Making Ice Without A Freezer.


Here is where I got bored and decided to make Ice without a freezer.

Here are some Photos of how I did this.

All I had was a thermoelectric peltier module, this removed from an old water cooler, 2 x 6 volt 200Ah (Amp hour) lead acid batteries (each weighed 45 Kilograms! ), some wire, a huge heat sink with fans fixed on, an old cardboard sweet container, 5 plastic bags, a roll of insulation tape, and some heat sink compound to ensure good thermal contact.

Thermoelectric modules are very clever, when you apply a DC voltage, one side gets hot and the other gets cold.

It is a sort of electric heat pump, it draws any heat away from the "cold side" and sinks it to the hot side)

Between each side of an unloaded module there is a typical temperature difference of around 25 Degrees C.

On the basis that if you cool the hot side down as much as possible the cold side will get even colder.

To do this simply bolt it to the biggest heat sink with fans you can find, this effectively dissipates the heat away from the module and cools the hot side, this then makes the cold side colder.

If we say that the heat sink is cooling the hot side of the module to around 17 degrees C, based on the 25 degrees C difference between each side this would make the cold side temperature 25 degrees C lower than the hot side, so hot side temp minus temp difference = cold side temp, or 17 - 25 = -7 so it makes it -7 degrees C, cold enough to make ice!

Next stick a small block of aluminum to the cold side (so sink the cold evenly) then stick what you want to freeze on the alu block, now use a container to keep the cold in i.e. insulate the cold side, after some time what ever you put on the alu block will freeze.

In my experiment I had water in a aluminum container on the cold alu block, I used an old cardboard sweet container wrapped with plastic bags to insulate (keep the cold in) after 90 minutes hay presto we have ice!

If you reverse the cycle and stick something big and hot on the cold side the hot side will get hotter and you can boil water on one!

Also if you reverse the DC voltage polarity the cold and hot swap sides!

Note:

NEVER run a thermoelectric module with just the bare ceramic on the hot side i.e. no heat sink / load, as if it gets too hot the solder that is used to connect the peltier network together can / will melt, also the ceramic can crack due to heat, then the module will be destroyed!

Here is a great Web site that tells you how they work.


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