Why 50 Hz in India??? Why 60 Hz in USA??? The history behind the power generation...

In India & Europe power is generated with 50 Hz frequency whether in USA power is generated with 60 Hz frequency. Now one can tell the reason that the British are using the power at 50 Hz so we are also using the power at the same frequency. Then the question comes why British people using 50 Hz why not 60 Hz like the USA? Now for this, we have to go through the story of power generation. So, let's start...

   

     

If you go to the era before Christ, people used oil lamps for their lighting purpose. After that, they discovered candles for artificial lighting. 

• In the year of 1792, they first got the gaslight.
• At the beginning of the 19th century, an Italian scientist first invented a battery. They were calling it a Voltaic Pile that was a dc battery by using a chemical process.
• Then after a few years, a scientist from Switzerland(Humphry Davy) used the battery to light up the carbon arc lamp. That was the first electrical energy usage. He had taken two electrodes & applied a very high voltage between them, so the air between get ionized which leads to an Electric arc.
• In the year of 1832, a British scientist used the dc voltage to convert it into mechanical energy by using dc motor but the design was not that good so there was more power loss.
• After that, a French scientist Hippolyte Pixi had first discovered a dc generator. Surprisingly he first got ac output from the generator, but at that time there was no use of the ac power so he converted the ac power by the use of a commutator. So, the use of the battery was replaced by the dc generator. 
• In the year 1855, a French neurologist Guillaume Duchenne first used the ac power source for electrotherapy. 
• In the year 1871, dc motor was developed to the practical world by  French scientist Gramme.
• Now in the year of 1873, French scientist Hippolyte Fontaine was first transmitted the electrical power for 2 km using conductors.
• In the year 1874 Russian scientist Alexander Lodygin first patented incandescent bulb, but the life span of the bulb was a few hours.
• Next in 1880 American scientist Thomas Alva Edison who was also a businessman,  invented practical incandescent lamp which can last for 1500 hours. Now to use his invention customers/consumers need a power source so he had started building commercial power plants in New York City. So he started transmitting 110V, 2 wire dc power. Now the question is why 110V? Edison wanted the load voltage to remain at 100V dc, but there is some transmission line drop for this reason he transmitted at 110V dc. Now the problem was that if the load increases then the load voltage becomes low because he used low voltage to transmit the power & as the load increases current becomes higher which leads to high transmission drop, so he had to install power plants after a certain distance. But the inventors were not happy with that idea so he revised the transmission system to dc 3-wire 220/110 V dc transmission system which reduced the losses to a considerable amount. But this idea was not helped a lot.
• In 1884 two British scientists, had given the idea of the transformer to step up the voltage level because if we transmit power at high voltage then the loss, as well as voltage drop, reduces. They built first ac transmission for demonstration in Italy with 1-phase 130 Hz power supply. They increased the voltage level to 2000V. Why they used 130Hz?? The answer is at that time electricity was only used to supply bulbs & if the frequency is low then the time period becomes high which leads to flickering of bulbs so they picked up a high frequency.
• In 1885 they build a commercial power plant in Italy with 2000V but 120Hz frequency. They have chosen 120Hz because they kept on experimenting with different frequencies and there were no standard frequencies at that time.
• Motors are very much needed for industrial purposes but at that time only dc machine was invented which can not be run with ac supply. In the year 1885 Italian scientist Galileo Ferraris has got the idea of ac motor by using polyphase ac supply, but he had not implemented the idea.
• In the same year, George Westinghouse purchased the idea of the transformer, and transmitted the 1-phase ac power in the New York city with higher voltage(500/100V) with 133.33Hz frequency in the year 1886. At the end of 1886, he had successfully launched the commercial ac transmission line with the same frequency but 1000/100V voltage level. By this technique, he has reduced the transmission line losses with a considerable amount, so there was no need for regular power plants at regular intervals. 
• In the year 1888 famous scientist Nikola Tesla got the polyphase ac motor patents which can convert electrical energy to mechanical energy. This idea had accelerated the use of ac power. Now there was a fight between Edison & George Westinghouse because Edison wanted to promote dc power but George Westinghouse wanted to promote ac power which is called War Of Currents.
• In the year 1891, in Germany, George Westinghouse transmitted a three-phase ac transmission line for a demonstration purpose. They transmitted over 175 km distance with 8000V transmission voltage and with 40 Hz frequency. They were experimenting with the frequency which will be good for their overall system. 
• In the year 1893, they had got the opportunity in participating to lighting up the Chicago World Fair. For that George Westinghouse had used 2-phase, 2200V, 60Hz ac power. Two-phase power was used to run the polyphase ac motors and 60Hz frequency was chosen because Tesla said that low frequency is good for his motors because at low-frequency hysteresis & eddy current losses are minimum but if the frequency is so less, then bulbs used to give a flicker. They could have used 40Hz but Tesla suggested 60Hz based on a simple logic that is, 1hour=60 minutes, 1minute=60 seconds, 1second=60 cycles i.e. 60Hz. That's how they landed at 60Hz transmission frequency.
• Now the question comes that why the European countries are using 50Hz? They could have chosen 60Hz but 60 number was not fitting into their metric system because European & US units are something different. So the had chosen 50Hz as the standard frequency which is nearest to 60Hz. So we Indians are also using 60Hz as a standard frequency.