Electricity can flow in two different ways; either in direct current (DC) or in alternating current (AC). Electricity is a moving electron through or along a conductor, for instance a wire, which have been connected for energy (Daly, Peckham & AudioGO, 2013). Therefore, the variation between DC and AC is the direction of electron flow. In direct current, the electrons flow in one direction (forward). In alternating current, electrons keep changing directions, sometimes forward and at times backwards (Daly, 2013).
Origins of DC and AC Current
A magnetic field next to a wire can make electrons flow along the wire in one direction, because electrons become repelled from the negative terminal and get attracted by a positive terminal of a magnet. This is how direct current power of battery was founded by Thomas Edison (Daly, Peckham & AudioGO, 2013). On the other hand, alternating current uses a rotating magnet. Whenever the magnet is oriented towards one direction, electrons flow towards a positive terminal, but when magnet orientation is flipped, the flow of electrons turn as well towards a negative terminal (Daly, Peckham & AudioGO, 2013). Alternating current generators replaced Edison’s direct current battery system, as alternating current was considered safer in the transmission of current over longer distances and provided more power.
Direct Current
Direct current may be generated in many ways: an alternating current generator with a device referred as a commutator may produce direct current; the use of a tool called rectifier which converts alternating current to direct current and batteries give direct current, which is generated due to chemical reaction in the battery (Daly, 2013). This last way of generating DC was designed by Thomas Edison.
Application of Direct Current
All electronics equipment and parts for trade on SparkFun operate on direct current. Everything which operates off of battery relies on direct current. Examples of direct current electronics include: Flashlights, cell phones, flat-screen TVs, and electric and hybrid vehicles (Daly, Peckham & AudioGO, 2013).
Edison’s Smear Campaign
During 1880s, the initial systems of electrical distribution were designed by Thomas, and were founded on DC, not AC, as they are currently. Thomas preferred direct current since it worked properly with his motors, storage batteries, and incandescent lamps. In a Thomas direct current network, generating firms fed 110 volts into gauge conductors, with consumer loads tapped off it (Daly, Peckham & AudioGO, 2013).
As it reached the consumer, the voltage dropped through resistance to approximately 100 volts, which corresponded to the 100 volt motors and lamps at the consumer’s location. On an account that voltage never have far to step-down or drop as a result of resistance within the wires, generating firms had to be established some distance from the load (Daly, 2013). Higher current would have permitted the power to be transmitted further, although there was no effective low-cost technology which could decrease a high transmission current to a low consumption voltage. That is, there was no economical direct current step-down transformer (Daly, Peckham & AudioGO, 2013). Lower voltages or current were preferred due to their safety.
Using rotary magnetic fields, Tesla designed an electrical distribution system bases on alternating current power. Nikola’s work interested Westinghouse, who invested to commercialize AC system (Daly, 2013). Unlike direct current, alternating current systems utilized a high current, long-distance distribution framework and transformers to step-down the voltage or current near the consumer locations.
In the ensuing battle of current during 1880s, Edison and Westinghouse battled for dominance of their own current distribution systems. Throughout this time, Thomas muddied his reputation or repute by conducting a major advertisement to ridicule alternating current. Besides, lobbying against alternating current in several states legislatures, Edison advertised fatal alternating current accidents, and openly killed stray dogs and cats with electricity. Moreover, he publicly tried to associate electrocution with Westinghouse. His ridiculous mischief turned serious when, even though opposed to capital castigation, he secretly paid Brown to make an electric chair for New York State by the use of an alternating current, and to expose that fact (Daly, Peckham & AudioGO, 2013).
Eventually, alternating current won out. This probably happened when, defeating an Edison proposal/General Electric, the Tesla AC/Westinghouse system won the global Niagara Falls Commission deal to exploit the power or electricity of Niagara Falls. Within 1893, work started on the generation development and soon, electric power were generated and distributed or transmitted as alternating current to New York (Daly, Peckham & AudioGO, 2013).
In the modern, Green Age, direct current has been slowly making a comeback. Laptops or computers based on direct current power supplies may yield 20 to 30% more performance than alternating current based electronics before they overheat (Daly, 2013). In the year 2006, researchers from Berkeley Lab grouped with approximately 20 firms, including Cisco, Sun Microsystems, and Intel, to show technologies within a facility of sun test in Newark, California which could help save billions of dollars annually within data center-linked costs. Rather than converting from DC to AC, and vice versa, to power the machines, they showed that using direct current exclusively during a data center may save approximately 10 to 20% in power costs, moreover, improve reliability (Daly, Peckham & AudioGO, 2013).
References
Daly, M., Peckham, M., & AudioGO (Firm) (2013). Topsy: The startling story of the crooked-tailed elephant, P.T. Barnum, and the American wizard, Thomas Edison. North Kingstown, RI: AudioGO.
Daly, M. (2013). Topsy: The startling story of the crooked-tailed elephant, P.T. Barnum, and the American wizard, Thomas Edison. New York: Atlantic Monthly Press.
