Why is AC better for long distance power transmission than DC ?

4 Answers

Answer :

Alternating voltages can be transported over long distance at high voltage and low current so as minimizing the ohmic loss in heat.. ... It is because AC does not allow the loss of energy in the form of heat. While using DC for long distance transmission can lead to a huge amount of energy loss.

Answer :

You are wrong. DC is better to be transmitted, because the only loss is the resistive one, in AC you have also inductive and capacitive loses, but DC is not used because the switching to a lower or higher voltage is much more expensive. In the past, it was available to switch the voltage level just in AC with low losses, DC needing high voltage switching electronics, that was unavailable at those times. Few evolved countries started to use high voltage DC transmission lines on very long distances.

Answer :

As controlling and FACTS devices mostly works on AC it is easy to control and for maintenance therefore AC is better for long transmission lines than DC

Answer :

ac is more economical to transmit for long distances . wires can be made smaller by step up transformer .. since major cost are wires to transmit .. then at the end of distance step down transformer is used for commercial use.

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