Like a true Greek, my favourite drink is Frappé. If you read the news lately you probably know that Greece is moments away from becoming a post apocalyptic wasteland like in Mad Max.
Now, while I have stockpiled enough instant coffee and sugar to last me to the heat death of the universe, I am lacking the third and most important ingredient to make Frappé, ice.
So how can I make ice without electricity? Note that other resources are going to be scarce or non-existant as well, so using for example a propane refrigerator is not practical.
I understand the Romans used evaporative cooling, but I’m guessing you’d need to start with a boatload of water with a large surface area to get a small amount of ice. I think I just may try this for giggles and see what happens.
A Hilsch (sp?) vortex tube. Though you’ll need lots of compressed air. It’s like magic. A pipe where hot air comes out of one end and cold air out of the other end.
A buttload of something like ether or acetone and lots of evaporative cooling might work. Or a compressed cylinder of CO2 and an expansion nozzle will give you lots of dry ice and you can use the dry ice to easily make water into water ice.
Or you could fix your economy. Might be easier in the long run.
Is it possible to attach a refrigerator’s compressor belts to a stationary bicycle? How long would one have to peddle to complete ice-formation? Since the compressor cycles on and off, could a battery-powered circuit let someone know when it’s time to peddle again?
Can’t find a reference to it now but it is possible to make ice in the Sahara using only a pair of clay urns.
I saw it on a TV science program and it is a technique used by the Tuaregs for centuries.
It roughly involves aiming and open throated clay urn with water in it at the night sky, the outer urn being for insulation purposes.
The night sky (clear sky) is sufficiently cold that the water radiates its heat and turns to ice.
Your location may or may not be suitable for this to work.
You could move chunks of gadolinium into contact with a magnet and then back away again. In one position it gets warm and in the other it gets cool (I forget which is which). You want to cool it to room temp when it’s in the warm position, then moving it into the cool position makes it colder than room temp. There was actually a plan some time ago to make refrigerators using motorized gadolinium pieces.
I’ve heard of this. You would put straw or other insulating material between the urns, or just use one urn and an insulated hole in the ground. I think on top of the cold temperature, very dry air does not conduct heat well so it doesn’t warm the urn, and doesn’t absorb heat well either allowing the heat emitted by the water to radiate away with creating a warm zone in the urn. While this method had been shown to provide substantial cooling, I’m still skeptical that this will produce ice without the ambient temperature dropping below the freezing point.
Gas refrigerator - saw them in Menorca. A flame under the fridge, a blue hot as hell flame making the food inside cold and the water into ice. It was explained to me that heating amonium (?) creates cold. Of course you need big tanks of butane to power it.
Propane refrigeraters are a very common and relatively inexpensive refrigerator. Extremely efficient, too - I have a decent size one one that keeps the freezer compartment at zero Farenheit or below, and uses very little propane. The burner, when it’s on, uses 1,800 BTU’s per hour, so it gets a little better than 51 hours out of a gallon of propane. Since the burner is on usually an average of only 50% of the time, one can figure on about four days of operation out of one gallon of propane (costing around here about $2.00 per gallon).
These can be found in all sizes, from small apartment types to restaurant sizes, and are extremely popular for off-grid use.
You need good quality energy energy and equipment to make make ice - assuming water is free. The better the quality of energy, the cheaper/easier the equipment to make ice. Here are the options
1> Best quality of energy :Electricity - Cheap Electric refrigerator
2> Next Best quality of energy : Propane - Propane Refrigerator
3> Little poorer quality of energy: Deisel/Oil - Run Generator - Electric Refrigerator (costlier equipment)
…
…
4> Poorest quality of energy : Biomass or Coal - Run small gasifier - Run Generator - Electric Refrigerator …
5> Well sunlight is a great quality of energy but energy density is poorer - so you can theoretically use a solar panel and a small refrigerator
You don’t have a lot of choices about how to make cold.
Gas laws - ie conventional refrigerators. Needs power to drive the compressor.
Radiation to a cooler place - ie shallow pool of water facing a clear night sky. Works, but not if it is cloudy, or the ambient temperature is much above freezing.
Peltier cell - ie the ruinously inefficient solid state coolers. Needs electricity, and lots of it.
Weird gas dynamics - Vortex tube - needs lots of power, not efficient.
Evaporation - latent heat of vaporisation. Need a volatile solvent to get properly cold. Probably impossibly inefficient, and expensive.
Endothermic chemical reaction. ie chemical cold packs. Probably worse than evaporation for expense of efficiency.
Absorption cooler. ie a propane/gas refrigerator. Not all that efficient, but the principle is interesting since it runs on heat. Viable and used. In principle any source of heat can be used.
