Solar Chimney:

In the US Army, as a young Engineer, I learned the acronym K.I.S.S. Not the rock band Kiss, rather; Keep It Simple Stupid. Present company excluded, the Uniformed Army Corps of Engineers was made up of people from varying backgrounds, some were highly educated, and others were simply motivated to teamwork. Some people had a knack for what was termed Field Expedience, which is akin to Yankee Engineering. The ability to use the materials on hand to do a job, and to implement it in such a way that if the person who may have to replace you can do so in a more easy transition; it was simple enough to understand how it works and how to operate it. Idiot proof is another term often used describe the principle.

The chimney effect is a principle which even the common ant and termite understand and use when building their homes. For centuries we have used Grain Silos to dry grains and prevent the build up of methane and hydrogen gasses which can cause spontaneous combustion. Spontaneous combustion begins when a combustible object is heated to its ignition temperature by a slow oxidation process. Oxidation is a chemical reaction involving the oxygen in the air around us gradually raising the inside temperature of something to the point at which a fire starts.

A grain silo allows built up gasses to vent without worry of rain or high humidity causing the grains to sprout or rot. Having the grains tightly packed into the round structure allows the right amount of gasses to react and keep the inside of the tube, the silo, at a higher temperature than the ambient air outside. Because temperature and pressure rise together at a constant rate, as in a pressure cooker, this temperature difference causes a pressure differential, or vacuum, to occur between the air inside compared to the air outside of the silo. As hot air rises, it creates a vacuume. Nature abhors a vacuum, and will always try to equalize the pressure inside the silo to that which is outside; constantly refilling the tube, the silo, with cooler, dryer air. This principle is known as the Chimney Effect, the same principle used to create a draft for a fireplace or wood/coal burning stove.

If we attach to the bottom of our tube a circular plate of glass with a hole big enough for our tube to fit into, and raise the two off the ground for a sufficient stand off to allow just the right amount of air to enter our tube/plate system, the sun will collect heat below the tube and store it in the ground. We now have a Solar Chimney where the earth below acts as a heat sink, or heat battery; constantly storing excessive solar energy in the earth to be used to create a high rate of relatively constant upward airflow.

Yank My Doodle, It's a Dandy!