Air conditioning
In 1902, the first modern electrical air conditioning unit was invented by Willis Carrier in Buffalo, New York. After graduating from Cornell University, Carrier found a job at the Buffalo Forge Company. There, he began experimenting with air conditioning as a way to solve an application problem for the Sackett-Wilhelms Lithographing and Publishing Company in Brooklyn, New York. The first air conditioner, designed and built in Buffalo by Carrier, began working on 17 July 1902.
George Westinghouse
George Westinghouse Jr. (October 6, 1846 – March 12, 1914) was an American entrepreneur and engineer based in Pennsylvania who invented the railway air brake and was a pioneer of the electrical industry, gaining his first patent at the age of 19. Westinghouse saw the potential in alternating current as an electricity distribution system in the early 1880s and put all his resources into developing and marketing it, a move that put his business in direct competition with the Edison direct current system. In 1911 Westinghouse received the AIEE's Edison Medal "For meritorious achievement in connection with the development of the alternating current system."