Why AC systems are preferred over DC systems?

Due to following reasons, AC systems are preferred over DC systems: a. It is easy to maintain and change the voltage of AC electricity for transmission and distribution. b. Plant cost for AC transmission (circuit breakers, transformers etc) is much lower than the equivalent DC transmission c. From power stations, AC is produced so it is better to use AC then DC instead of converting it. d. When a large fault occurs in a network, it is easier to interrupt in an AC system, as the sine wave current will naturally tend to zero at some point making the current easier to interrupt.

AC transmission is preferred over DC transmission because the power loss is much less as compared toDC transmission is less cost effective.

The ultimate reason is that it is much more ECONOMICAL.

AC (alternating current) is much easy to produce because it is the natural ouput of the generators and much more economical to transmit big thanks to the step up step down transformers. High voltage AC can be transmitted longer distances with less loss. This is allowing to use much less conductors again much more economical. Also AC induction motors are much cheaper allowing to use tree phase AC power which has greater efficiency. Again much more economical. Balanced three phase AC power is constant and it provides starting torque for industrial motors. This facilitates using simpler systems, easier to maintain and much more efficient. Therefore much more economical.