How is Alternating Current (A/C) more efficient for long distance transmission of electrical energy?
In mathematica terms?
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May 1st, 2010 at 3:32 pm
The conversion of electrical power into heat — that is, transmission losses — depends solely on the current flowing in a wire, not on the voltage. Since electrical power is the product of the current times the voltage, you can transmit electricity over very long distances with very small losses if you make the voltage huge and the current tiny.
With DC, this is purely a hypothetical thought; you’d have to generate the electricity at tens of thousands of volts and then pipe it in to homes at the same voltage! This is very dangerous, and not in any way desirable.
However, alternating current can be altered with a transformer into a higher or lower voltage, arbitrarily. The power level through a transformer is unchanged, so if you increase the voltage ten times (for example), the current is reduced to 1/10 — and so are the transmission losses!
Thus, by using transformers to convert AC into tens of thousands or hundreds of thousands of volts, it’s possible to send the power very far indeed with acceptable losses. This would be nearly impossible with DC.