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The "Cool Brick" Can Cool Off an Entire Room Using Nothing But Water
ErnieKey writes Emerging Objects, a company which experiments with 3D printing technology, has created what they call the "Cool Brick." Using basic concepts of evaporation, it holds water like a sponge, takes in hot dry air and converts it into cool moist air. 3D-printed with a specially engineered lattice using ceramics, it can be formed into entire walls which could be placed in different rooms of a house or building, thus replacing the need for air conditioning in hot, dry climates such as deserts.
evaporative humidifiers work great until they start breeding molds and algae. The water channels need to be cleaned and the screens replaced. The screen in this case being a wall in the house.
I am not an engineer (nor a zombie for that matter) so excuse me if I am wrong, but aren't you essentially describing how an AC unit works?
No. An AC unit takes advantage of gas pressure laws. It compresses a gas, then allows it to expand. As the gas expands, its temperature drops. By wrapping all this up with a set of radiator coils and fan(s), you can pump heat from inside to outside. Along the way, the cooled air will drop any water vapor that exceeds the carrying capacity for that temperature.
So an AC requires a pump (which can be mechanical or a heat source) and air recirculators, and the net result is air that is both cooler and drier.
A swamp cooler is almost completely passive. It needs a mechanism to inject the water, and (preferably) something to help the water-laden air move, but instead of lowering room humidity, it raises it.
Two problems.
First, the problem that every evaporative cooler has: water is scarce in the hot dry places where evaporative cooling works well.
Second, water always has some minerals dissolved in it that crystallize out when you remove the water. A traditional swamp cooler has an active flow and a reservoir that you have to empty to keep these from building up, but with these "smart bricks", the pores in the bricks are going to fill up with lime and gypsum, and pretty soon they'll be "dumb bricks".
Oh, and by the way - do you know what the gas is that is responsible for 95% of Global Warming? No, not CO2. Water Vapour. I wonder why no one has called for this invention to be banned out of hand...?
First, most water vapor in the atmosphere comes from natural sources. Unless you're planning on eliminating oceans, lakes, rivers, swamps, wetlands and rain (and thus killing all life on earth), the amount of water vapor in the atmosphere isn't going to change.
Second, Water vapor condenses and precipitates out of the atmosphere naturally, so it doesn't build up beyond the levels that are already there It's not a problem. CO2, on the other hand, does not condense and precipitate out of the atmosphere naturally (unless you drop the earth's temperature to -147ÂC, that is, which would kill almost all life on earth and leaving it for the tardigrades to inherit). It does build up and it is a problem.
It's not bullshit. Many commercial buildings in hot dry climate use evaporative chilers. You can also get devices that do it indoors. The issue with doing it indoors, is that once the air becomes saturated with moisture it stops working. Plus the room gets wet and cold, which is not a good environment, it leads to mold and mildew. Indoor evaporative coolers are best used in places that you only want to cook on rare occasions, that are very dry, and are located far from a window.
British houses have a double-brick-wall construction, mostly.
The idea is that the outside wall can get as wet as it likes (and it's Britain, so it gets wet!) but the internal wall is separated by an air gap. Whenever you join the outside wall to the inside (e.g. cables, etc.) you have to be careful how you do so so that water can't transfer between the two.
You still put in vents, etc. to get some kind of airflow from outside to in, however, because without vents (and with modern double-glazing especially) you just end up with condensation everywhere inside and mould in your internal plaster.
And one of the biggest problems with old houses built like this is still damp (there's no such thing as "rising damp" by the way, but that's another matter) and mould.
Having a wall with water in it is not a good idea, certainly not inside a building. We specifically build our houses to account for this and it's still possible to get mould inside if the water breaks through or settles inside.
The only thing that could combat it is a very good airflow so that water can't settle which, shockingly, will cool those kinds of places anyway.