Zero Electricity DIY Air Conditioner

Drops the temperature by 20 degrees F.

http://mashable.com/2016/06/09/eco-cooler-plastic-bottles-no-electricity/#SM.GqC6X48qN

Interesting. I wonder if it actually works.

You can make an evaporative cooler that works without electricity as well, but it requires a bit of upkeep and a low humidity environment.

Not sure how the bottles compressing the air would drop the temperature, but this setup would at least promote airflow. And it's an excellent use of junk.

It's probably is good for about 40hp on an ND as well.

Many things are wrong here. First, compressing air heats it. Second, those things won't compress air, they'll reduce pressure and accelerate it. Third, I don't see how these would be better than just a wide open window. If a person is standing in front of it they may feel cooler in a very light breeze (since the small streams of accelerated air will cool them off better), but in a heavier wind these things will only reduce airflow. This certainly can't drop the temperature of a room, at least not better than an open window.

I have another idea on how this may have some effect: It blocks almost all of the light from the window while still letting some breeze through. It could be that the reduction of light entering the window has more effect on room temperature than the reduction of airflow.

So if the backing board were made of clear lexan it wouldn't work.

In reply to GameboyRMH:

That would be my best guess as well, the bottles are catching most of the breeze and little of the sunlight.

In reply to GameboyRMH:

So.. he's using it as a funnel, not actually compressing the air, but speeding it up. So volume through smaller area, no closed container so no actual compression, just like a thumb over the end of a garden hose.

In reply to GameboyRMH:

I think you're right.

Some Key West style window shutters would probably serve them better.

There is something called a vortex tube that can separate hot and cold air as it flows.

http://www.newmantools.com/vortex.htm

It's probably not what's happening here, but I thought of it when I saw this, and there might be other issues at work.

Compressed air (or any gas/fluid) does gain heat from the compression. But, cool it then re-expand it, and it becomes chilly. I.E., conventional air conditioning or even the compressed air systems used on jet airliners.

That said, I agree that this setup is most likely just increasing air velocity, which isn't a bad thing. In the areas this is used in air flow is low and the rooms feel stifling, even with windows open. This blocks solar energy while allowing air flow, and creates a small jet stream flow for more dramatic cooling when near it.

So all in all, I'd say this is a good win for the intended users.

When the air compresses, it will absorb heat from the surroundings, and it will get warmer and the surroundings cooler. The same thing happens when it expands, the heat will go back to the surroundings.

So if the wind was coming from the open end of the funnel, it would compress and take heat up from the air in front of the board. So it's making that surface cooler.

It would probably be more effective if the funnels were within the space that you wanted to cool. But then you'd have to continue the compressed air until it's out of the house. (i.e. tubes running to the opposite wall) You'd want to insulate them too other wise they might radiate heat off and it would be counter productive.