Perhaps more than any other individual, Nikola Tesla was responsible for developing the AC (alternating current) system of power supply that provides theworld with electricity. A prolific inventor of keen intelligence and exceptional insight, Tesla patented more than 700 inventions in his lifetime.
Born on July 10, 1856, in Smijan, Croatia, Tesla was the son of a clergyman about whom little is known. Tesla may have acquired his knack for inventing from his mother. Although illiterate, she was a clever person who invented numerous implements for use at home and on the farm.
Tesla studied mathematics and engineering at the University of Graz and philosophy at the University of Prague. From the start, he was especially interested in electricity, and in 1881 he took a job as an electrical engineer in Paris, where he designed equipment and repaired power systems. It was around this time that Tesla first developed the polyphase synchronous motor, a "brushless" motor which would revolutionize the electrical industry. At the time, power was supplied by direct current, which was reliable but could not be delivered over great distances like AC could. In addition, the DC motors then in use contained brushes which sparked as the motors spun, limiting their maximumvoltage. Not only could Tesla's motor convert the zig-zag impulses of an alternating current into a spinning motion in one direction, but it could run athigh voltages with no danger of sparking.
Though Tesla was convinced that a system of AC using his motors should be used to supply power, he could not persuade his employers to consider his system, and he decided to leave for the United States to try his luck there. He washired to work in Thomas Alva Edison's laboratory, and although Edison developed enormous respect for Tesla's brilliant work, he was no more receptive toTesla's ideas than the Europeans had been. Edison and Tesla hotly denounced one another, and following an argument over wages, Tesla quit in 1885.
Tesla was approached by a group of promoters and formed his first company, the Tesla Electric Light Company. He went into competition with Edison, developing an arc lamp for use in lighting streets and factories. This venture proved to be quite successful, earning Tesla seven patents. But Tesla was swindledby his financiers and had only a worthless stock certificate in his possession when he was forced out of the company.
During this low point in Tesla's life, he worked as a ditch-digger. In 1887 Tesla's sympathetic foreman introduced him to an official at the Western UnionTelegraph Company, who provided him with the backing to start a company onceagain. Soon Tesla was devising a flurry of inventions in the laboratory of his Tesla Electric Company: split-phase, induction and synchronous motors, generators, transformers, all manner of electrical equipment. Soon his work cameto the attention of one of the most important businessmen of the day, GeorgeWestinghouse.
Shrewdly anticipating the future, Westinghouse offered Tesla a large sum forhis patent rights to the polyphase induction motor as well as a royalty on power generated. Westinghouse also gave the inventor a job as a consultant. Outbidding Edison, Westinghouse and Tesla arranged to provide the Columbian Exposition of 1893 with AC power. This victory paved the way for an even greatertriumph late that year when Westinghouse was offered the first contract to harness Niagara Falls for electrical power. By 1895 a generator was in place and two years later the Tesla generators were supplying electricity to Buffalo,New York, 22 miles (35 km) away. The Edison Company scrambled to catch up, and began installing AC transmission equipment at all of its power stations.
Around this time, Tesla was bursting with creativity. He became captivated bythe generation of high-frequency currents and built a machine that producedfrequencies of up to 25,000 cycles per second. Machines of this type would play an important part in the development of radio--and, in fact, Tesla had demonstrated the principles of wireless transmission of signals as early as 1893. In 1898, when Guglielmo Marconi was just beginning to send crude Morse codemessages over long distances, Tesla was demonstrating a radio-controlled model boat at Madison Square Garden. This early forerunner of robots was so farahead of its time that the baffled United States Navy could not see any use for such a device.
Tesla also began work on higher-frequency devices, the most important of which was Tesla coil, or resonant air-core transformer. The Tesla coil could produce current of almost any frequency and magnitude.
A mesmerizing speaker, Tesla traveled throughout Europe and the United Statesexhibiting his devices and lecturing. Often his lectures included spectacular trickery. For example, he astounded audiences by illuminating fluorescent tubes without any electrical connections using his Tesla coil; he magically spun a metal egg on a table, using an induction coil hidden below; he shot "artificial lightning" bolts through the room; and he sent one-million volts of AC current harmlessly through his body.
At times, Tesla's insight into the future of technology was uncanny. He intended his experiments with his robotic, remote-controlled boat to demonstrate that a day would come in which wars would be fought with such devices. He experimented with creating a particle beam, and attempted to devise a high-speedturbine, but failed because metal alloys strong enough to hold it together did not yet exist. Tesla was one of the first to advocate the use of solar andgeothermal power to obtain energy, and he even described the principles of radar, and electronic television before either existed.
Unfortunately, Tesla's enthusiasm for innovation began to get the best of him, and his ideas, though often visionary, became more and more impractical. Hebecame obsessed with the possibility of broadcasting electric power throughthe air, and lost millions on a pair of grandiose towers he built in Coloradoand New Jersey designed for this purpose. The second of these towers was intended to broadcast power and radio worldwide, but Tesla went bankrupt beforeit could be completed, and it was demolished during World War I as a potential security risk.
Such disastrous projects had lost Tesla the support of his old friend Westinghouse. When another of Tesla's patrons, J. P. Morgan, died in 1913, Tesla faced financial ruin. Over the years, his hot temper, flamboyant spending habits, and opinionated manner had damaged his reputation among the businessmen hedepended upon, and Tesla was left nearly penniless. He spent the last years of his life in increasing seclusion, feeding the pigeons daily on the steps ofthe New York Public Library. Only occasionally did he break his isolation tospeak to the press about a new invention he was working on, or to make eccentric claims. He died quietly on January 8, 1943.