Thomas Alva Edison holds 1093 patents on his inventions, which include such inventions as the incandescent light bulb, the phonograph, and direct current (DC). The latter being one of the most important and influential inventions since it was the first current to be invented. However, like any invention, it got its competition, this time, in the form of Nikola Tesla’s alternating current (AC). The war of currents between Thomas Edison’s direct DC and Nikola Tesla’s AC forever changed electricity and the way mankind lives.
In order to be able to develop a successful incandescent lightbulb, Edison, had to first develop an entire electrical system, which he modeled after the gas lighting systems used in large cities. Gas systems had central stations, underground conductors, meters, and lamp fixtures. In addition to all of this, Edison also had to make an electrical generator and the network it powered. And so, Edison developed DC, which continuously runs in one direction. DC can be achieved electrochemically by fuel cells and batteries or electromechanically by some specific types of generators. It is also possible to produce it using photovoltaic devices. Edison created a DC system that was most efficient in heavily populated cities and for isolated plants generating power for a single building. This system was more efficient and economical within a square mile of its central station. Edison’s DC was, at the start of the electricity industry, the standard in the United States for providing electricity since DC not only work very well with incandescent lamps, but was also able to be used directly with storage batteries, providing valuable load-levelling and backup power during interruptions of generator operation. In addition to that DC generators could be easily paralleled, allowing economic operation by using smaller machines during periods of light load and improving reliability. Edison also made a meter so that customers were billed based on how much energy they consumed. The DC system however, had one very simple flaw, which was that it couldn’t be easily converted to higher or lower voltages.