Aquila Children's Magazine The Electric Issue - Page 15

PROS AND CONS OF DC VERSUS AC IN LATE 1880S
more , it can be stepped up or down depending on how much is needed by its users .
Tesla ’ s enthusiasm for this system was infectious . ‘ Is there anything more fascinating than the study of alternating currents ?’ he asked , when lecturing at the Royal Institution in London in early February 1892 . People clapped the extraordinary scientist , who thanked them all afterwards and said modestly that he was only building on what others had achieved before him .
In 1886 , an American engineer called George Westinghouse had already set up a network distributing AC power . The system had been tried successfully in England , too : one of the first places to use it ( as early as 1881 ), was the small town of Godalming in Surrey , where water at a local watermill was used to drive an AC generator . But Edison , who had spent a great deal on his system and hoped to make a lot of money from it , was not giving up . To him , Tesla ’ s ideas were ‘ magnificent , but utterly impractical ’. Now he thought of a way to prove it . Sadly , some people had already been accidentally electrocuted by overhead AC wires , so Edison set out to demonstrate the risks of having this kind of electricity in the home . Wouldn ’ t Edison have been better off perfecting his own system , rather than spending time smearing his competitor ?
By then , Edison had lost his battle anyway . In 1895 Tesla and Westinghouse had built the first hydroelectric power plant at the famous Niagara Falls . Using Tesla ’ s AC motor , which was driven by the sheer force of all that water , they were able to supply power to the whole town of Buffalo . It was a short step from this towards the electrification of the modern world by the AC system .
Sometimes a little rivalry can really benefit humankind . Great minds don ’ t necessarily think alike . They may even be opposed to each other . But we owe a huge debt to both Edison and Tesla . Between them they laid the basis for the technological revolution of our own times .
Besides the electric light bulb , Edison is credited with many more inventions . These include the phonograph , which was the first machine to reproduce sound , and the early moving-picture camera . The way Edison encouraged innovation

PROS AND CONS OF DC VERSUS AC IN LATE 1880S

Pro ( that is , For )
Con ( that is , Against )
Direct Current ( DC )
Always flows in one direction
Batteries run out and need replacing or recharging
More efficient over short distances
Cannot travel long distances
Cannot vary power
Alternating Current ( AC )
Can travel longer distances
Requires transformer
Can step voltage up or down
was influential too : he drew on many talents to produce new discoveries . Tesla worked more independently – and with an imagination that was constantly firing off new ideas – inspired many other developments , from radios , robotics and remote control to solar energy and microwaves . Despite all the backbiting , in the end we needed both of these amazing geniuses to get where we are today !
* The truth is more complicated . Many people contributed to the invention of the light bulb . Joseph Swan and Thomas Edison share responsibility for helping to make electric light both practical and cost efficient .
Find out more about the Niagara Falls Power Plant at teslasociety . com / teslawestinghouse . htm – and there are some fun facts about Edison at easyscienceforkids . com / all-about-thomas-edison /
Words : Jackie Banerjee . Illustration : Paul Ryding
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