Science Forums 2

[Nitack]

I once heard of a house built in the California desert that used a natural and energy free form of air conditioning. It was quite ingenious the way they did it.

Once you get about five feet below ground the temp hits a constant 50ish degrees F (I am in the US, don't know C that well). So what they did was to dig multiple trenches around this house to a dept of ten feet. They had those trenches zig zag while leading back to the house (you will understand why later). From that point they laid corrugated steel pipe in the trenches. At the ends farthest from the house they had the pipes surface above ground, covered the top with a wire mesh and a hood so as rain could not fall in it. They covered over the pipes again and watered as the soil was put back in to help it settle to the same density it was prior to being dug up. The connection of the pipe to the house was at the lowest point in the house (presumably the basement). From there they proceeded to as tightly weather seal the house as possible. The thing was as airtight as they could make it. Then, they installed an attic vent at the absolute top point in the roof.

From there is was basic physics. As air in the house heated up it flowed out of the attic vent due to its higher density than the cooler air in the house. As the air flowed out though the pressure difference drew in air from the pipe at the lowest point. That air had been flowing in underground where most of the heat had been lost to the ground and the air flowing in was in the 50-60 degree range. From there it was just a matter of air flowing through the pipes, cooling, becoming dens and flowing through the house due to the lack of pressure because of the air leaving through the attic vent.

I thought it was genius and wanted to do it on my own house, but the humid air in Virginia would have created issues with condensation, mold and such. Might not be a bad idea for some Australian homes though...