I’m curious about the really old ice boxes, but I was really wondering about the ones from the 1800s that relied on coolant and some form of evaporation.
I can’t really picture how old is physics work without electricity.
In: 47
Refrigeration is about phase change and requires electricity to pump a fluid through a condenser and an evaporator.
Ice boxes were just well insulated boxes full of ice.
I’m not familiar with evaporative coolers in the 1800’s, but if they existed, I can’t see how they would work without a fan, which requires electricity.
Root cellars!
I remember behind my grandparents house was a cellar they had dug out years ago. It went down about 10 feet and had a large mound of dirt on it. It was always way cooler down there than outside.
Some of the early refrigerators used a block of ice shipped in from somewhere.
There were cool boxes that used evaporation of water sometimes called a pot in pot cooler. They were made of two pots; an inner metal or glazed ceramic pot which held the food and an outer pot made of porous unglazed pottery. The outer pot is wetted, or damp material like sand is placed between the two pots. As water evaporates from the outer surface of the outermost pot, it pulls heat from the pot, cooling the contents, it will keep things relatively cool until the water all evaporates. It’s the same principle how sweating keeps you cool.
The original iceboxes were literally well-insulated boxes with a drawer at the top in which a large chunk of ice was stored. It cooled the air in the box and kept the food chilled. You’d have to empty a drip tray every day or so. As for the ice – there’s a good chance it was shipped all the way from New Hampshire and the people who handled that trade became incredibly rich.
[https://en.wikipedia.org/wiki/Ice_trade](https://en.wikipedia.org/wiki/Ice_trade)
The earliest closed-system vapor refrigeration systems were powered by steam engines. The steam engine would run the pump and the pump would move the refrigerant through the sealed system.
In my hometown city, t hey cut up blocks up ice from the river in the winter. Then stored them deep in specialized basement covered with sawdust to be distributed through the spring and fall.
Ice Blocks were delivered to and from via horse drawn carts. The saw were manually operated and lifted by really strong guys.
A couple points to be made here.
Really old school ice boxes were literally just a box you’d put ice in. They’d harvest and store ice over the winter and deliver it to customers.
Nothing about refrigeration requires electricity. You can power a fridge with propane, a waterwheel, compressed air etc.
To run a mechanical refrigerator, you need a compressor driven by *something*. Home systems use electricity because it’s quiet, safe, reliable, compact, etc.
But if you are a commercial operation, you can just have a steam-powered compressor. You can have crews to feed and maintain the steam plant. Rather than burn coal to power a steam engine that turns a generator that sends electricity to a motor that turns a compressor, you can just direct-drive the compressor from the steam engine. This allows you to make ice to sell directly (for home ice boxes) and also to fill ice containers for insulated railroad cars used to keep food cold in transit.
And also you can fit such a refrigeration system on a ship so it can carry frozen meat over long distances. Electricity is needed for a practical refrigerator in your house, but it isn’t needed for frozen meat or refrigerated milk/fruit to be part of your diet.
Absorption refrigeration runs off of heat, not mechanical work. It was one of the earlier popular cycles and can run off of any fuel that generates heat. These days they typically use propane.
Since no one has mentioned them yet, the Persians built Yakhchals. They had all sorts of clever passive cooling methods, wind towers (badgirs), cool air from underground aqueducts (qanats) and could make ice. The technique was to have a shallow pool of water open to the sky protected from the sun and hot winds by shade walls and as insulated from the ground as possible. At night the heating of the pool by convection or conduction is minimal while the heat loss by evaporation and especially radiation is large enough that ice forms and can be collected and stored in the basement of the Yakhchal.
You would buy ice and put it in an icebox (a well insulated box that predates refrigerators) and kept your food cold in there.
If you lived in an area that got ice in the winter, you could collect ice from a lake or something and bury it in sawdust and take ice out from there in the summer when you needed it for your icebox. Sawdust is a surprisingly good insulator. Industry based omarou d selling thr ice would have well insulated buildings called icehouses.
If you didn’t live somewhere that got ice in the winter, you could buy ice from somewhere that did. Before refrigeration existed, they would just pack a ship full of ice and sell what didn’t melt by the time they got there. After refrigeration existed, some place with electricity could manufacture ice, or you could transport ice for cheaper thanks to refrigerated train cars.
As for the evaporative coolers, when matter changes state, it has to absorb or release energy called latent heat. When a liquid evaporates, it absorbs the latent heat of vaporization, taking energy away from the environment. When it condenses, it gives that energy back. This is exactly how modern AC and refrigeration works, just in a closed loop, carrying heat from inside to the outside. The evaporative coolers rely on the coolant evaporating and the air carrying the vapor away.
Latest Answers