Also called wind towers and wind scoops, windcatchers have been used in North Africa and the Middle East for thousands of years to provide natural ventilation & passive cooling. They fell out of popularity after the introduction of HVAC systems, but are now experiencing a revival because they’re so practical and cost-effective. Here’s how they work:

Not only are they an engineering masterpiece–they’re gorgeous

The wooden rods protruding from the sides serve a variety of purposes. They stabilize and strengthen the structure, serve as scaffolding [1], and can be used to mount cloth and re-direct airflow [2].

Windcatchers vary greatly in design, and are tailored to individual building sites. The location’s airflow direction will determine the windcatcher’s shape, and the number and direction of its openings. (Windcatchers can be uni-directional, bi-directional, or multi-directional [3].)

The way the air flows through a wind tower is determined both by local conditions and by its cross-section design. Internal walls divide the tower in order to influence the way air passes through the building (see diagram) 

Windcatchers can be much smaller than the examples shown above! More modest structures like the one below can provide affordable ventilation to smaller buildings. 

Windcatchers can also be used to provide subterranean cooling, by ventilating underground structures, or evaporative cooling when used in conjunction with qanats (underground water chanels) or indoor bodies of water.

Due to the high cost and heavy CO2 emissions of electric air conditioning, windcatchers are receiving renewed interest. Specifically, architects are researching ways that windcatcher technology can be improved and adapted to modern times [4]. Long-standing issues with traditional wind towers include performance problems such as air short circuiting, and practical issues such as the ingress of dust, insects and small animals. New concept designs are emerging all the time, and some have already been built, and are being used in cities and universities throughout the Middle East.

In conclusion, be excited about windcatchers!

they perform as well as expensive HEPA air cleaners, and are comparatively VERY inexpensive. all you need is a box fan, 4 air filters, a piece of cardboard, and some duct tape!!!!

Next slide. “Brandon Sanderson is a member of the LDS”. The muttering has changed tone

“It’s not a very big amount of money though.” Someone in the audience pipes up. “His cut is only a small fraction of the cost of the book, and then-“ my next slide shows an income breakdown, it is titled ‘a small fraction of $10,000,000 is still a big number’