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this is a bad year an ancient air conditioner invented around the 8th Century A.D despite using no electricity it has a cooling system during the hot summer months however in the winter the
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building still remained warm and comfortable these buildings are found across Iran but they are most prevalent in the ancient city of yes as you can see this city is surrounded by extremely dry and desert conditions
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the climate is pretty extreme with the hottest month being July which has an average temperature of around 38 degrees Celsius or 102 Fahrenheit and the highest recorded temperature in the city
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was a whopping 46 degrees Celsius that's 115 Fahrenheit there is also little to no rainfall throughout the year with the average annual rainfall being somewhere between
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0.4 to 0.7 millimeters it's crazy to think even today in this city most buildings do not have modern air conditioning but instead they still rely on the ancient air conditioning system this is because unlike powered air
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conditioning and fans bed gears are silent and continue to function when the electrical grid power fails the bag ear literally translates as wind catcher it's a traditional structure used for
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Passive air conditioning of buildings it works by creating cross ventilation and passive cooling Wing catchers come in very designs depending on local prevailing winds
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they can be unidirectional bi-directional or multi-directional and despite the name these wind catchers can also work without wind wing catchers rely on local weather and microclimate
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conditions and not all techniques will work everywhere Wing catchers work in a few ways the first and most common is to cool the inside of the building the tower has openings that are facing the
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wind and trap it inside creating a nice breeze inside the building when used with a connect which is an underground water Channel or pool air is drawn down it reaches the water and then is drawn
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up to the wind catcher to be dispersed into the building when there is no wind the wind catches a like a chimney letting the hot air rise and escape the wind catchers can also be used with a
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filter to stop dust particles and pollution entering the building there are hundreds of these wind catches and yes which is a city entirely made of adobe there are also lots of dome-shaped roofs
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with small holes on top these shapes also help to keep the air inside the building circulating and therefore cool when it's hot and warm when it's cold outside these shapes and structures are
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also widely used in North Africa West Asia and India paintings dating back to around 1 300 BC discovered near modern day Egypt depict two triangular structures atop of a Pharaoh's Royal
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residence leading archaeologists who believe this was the first wind catcher developed but still it's unclear which country or culture invented these architectural designs first but the idea
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of keeping buildings cool have clearly spread far and wide with variations depending on the region since the early 20th century modern day housing has failed to design houses to
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stay cool instead favoring electric powered air conditioners which are more prevalent than ever and they account for 22 of all the total electricity used in buildings around the world today however
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in the last decades modern architectural designs have been looking back towards these ancient techniques by using the concept of the wing catchers to create buildings that are more cost effective
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and environmentally friendly such as this new 33-story double-skin tower in Pittsburgh which is utilizing thermodynamics these engineering techniques are also
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essential for off-grid buildings such as this desert school in Rajasthan which is located in the middle of nowhere if you like this video and love ancient technology make sure to check out these videos here thank you for watching until
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next time
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