permaculture

["Lawrence F. London, Jr." <lfl@intrex.net>]

Marimike6@cs.com wrote:

> Prevailing breezes above roof level are frequently as much as 15-20 degrees 
> cooler than ground level air. In Pakistan for the past 3,000 years people have 
> put tall vents atop their homes, with the openings angled toward the 
> prevailing winds. That way when it gets to be 120 degrees outside, a cooling 100 degree 
> breeze can circulate down the shaft and into the home.

Passive cooling has been around forever in the Middle East, perhaps even 
before the Islamic Moors of
North Africa (or were they originally from the middle 
east/Mediterranean/breadbasket area?) colonized Southern Spain,
built the Alhambra and started the first university and the first library while many of our ancestors were running 
around in bearskins proving Darwin's theories and, no doubt, brought solar cooling to the West as well.

They build masonry solar chimneys between a large domed cistern and a multi-storied dwelling. The chimnet has openings 
near the top with metal plates mounted vertically and set back from the opening. The sun heats the plate and causes
convection currents in the tower. This pulls cool damp air from the cistern into the dwelling, up throug the floors to 
finally exit through a wall back into the chimney and out the top.