There was a technique used or invented
by the Romans a long time ago. A natural form of air conditioning
/ ventilation was used roughly as follows:
- A trench 6 to 12 feet deep and 100 to 200
yards long was dug leading from the "house" in a straight
line away from the house.
- Into this trench a large diameter pipe (these
days corrugated drainage pipe 2 or 3 feet diameter) was laid,
with holes drilled into the bottom to drain water that condensed
inside the pipe. The trench was then covered over.
- At the far end a 90 degree elbow was attached
and more pipe added so that it reached above ground and the end
covered with some sort of wire mesh attached to keep out unwanted
things such as rodents, etc., and then another elbow could be
added at this end to shield against rain.
- The house end of the pipe entered the house
and was the source of incoming air.
- The key to making this work is to add a convection
chimney.
- The Convection chimney is built such that
it's inside opening is at a high point inside the building.
- On the outside, two intersecting sides of
the chimney; are painted flat black, and the resulting V formed
by the two connecting sides face south. In other words, the V
needs to face the mid point between where the sun rises and sets.
- The two other sides must be transparent,
Plexiglas or some equivalent. Also, the higher/larger the chimney,
the better.
How it works: the sun heats up the chimney causing
the air inside to rise, thus drawing air through the cool pipe.
The pipe cools the air drawn from the outside to the temperature
of the earth at the depth at which it is buried (which is virtually
constant year around at this depth). By the way, an interesting
note: Even in cold climates where the ground is frozen, the incoming
air is only 32F when the air outside may be much colder, we need
only heat the air by 38F to bring it to 70F; as opposed to heating
outside air of say -15F to 70F we would have to heat the incoming
air by 85F - quite a difference in the amount of heating energy
we would have to supply by some other means.
Of course, without the sun to warm the chimney
(or some other source) the system isn't worth fooling with.
