9781422276860

A History of Air-Conditioning

Ancient China: An inventor named Ding Huane builds a room-sized, manually powered rotary fan. Ancient Rome: Wealthy homeowners use aqueducts to circulate cool water through the walls of their homes. Third Century Rome: The emperor Elagabalus has workers build a mountain of snow (carried in from the mountains) in his garden next to his villa to stay cool during the summer. 18th century: The American inventor Benjamin Franklin experiments with evaporation and alcohol to achieve freezing temperatures. 1820: The British inventor Michael Faraday discovers that he can cool the air inside his laboratory by compressing and liquidizing ammonia and then allowing it to evaporate. 1881: Naval engineers build a basic air-conditioning system that consists of air blown through cotton sheets doused in ice water for a dying President James Garfield. It’s estimated that the machine uses half a million pounds (226,796 kilograms) of ice in two months. 1902: Air-conditioning as we know it today is invented by a young engineer named Willis Carrier. His initial goal is to create a system to reduce humidity (the level of water vapor in the air) at a printing plant. 1914: Air-conditioning is installed in a home for the first time. 1931: The window air-conditioning unit is invented. 1939: The first air-conditioned car is invented. 1953: More than one million air-conditioning units in the United States are sold. Today: About 75 percent of homes in the United States have some form of air-conditioning. The use of air-conditioning varies greatly around the world, but it is growing. The Future: An estimated 700 million air-conditioners are expected to be installed around the world by 2030. Sources: Slate, Popular Mechanics, Lawrence Berkeley National Labo- ratory, U.S. Department of Energy

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