Why are homes powered by ac and not by dc current?

Answer 1

power station may also provide dc voltage with using of dc generator but it is not economical to transmit the dc voltage. Since the step up and step down of dc voltage is not possible directly using Transformers, we'll have to transmit domestic supply voltage (DC, as your inquiry). But transmission of a DC voltage over lengthy lines would result in a much less voltage at receiver's end.

So, considering the efficiency, economy and easiness, AC is preferred to DC.

Answer 2

At the time, DC had many limitations (most of which have been overcome). Edison wanted Direct current, but the issues just could not be overcome.

Power is lost when transmitting it, with AC wasting more due to acting like an antenna. For DC, or the same component of AC, the power wasted is the current squared times the resistance of the material (or the voltage drop across it times the current). An existing technology called transformers are easily able to change the voltage of AC power. Increasing the voltage will reduce the current (the are inversely related for fixed power being transmitted). This means for AC, power could be transferred at high voltage, using low current for the majority of the distance, and then low voltage, high current for a short section.

At the time the decision was being made, no similar technology existed for DC, meaning the entire system had to be run at high current low voltage, with much higher losses.

Answer 3

It's easier to generate.

AC can be stepped up and down to different voltages quite simply, and the high voltage can be transmitted over long distances with less loss of power. Up to 400 000 volts in the UK.

In many ways it is safer. If you grab a live AC wire your muscle contractions will tend to throw you away. If you grab a high voltage DC wire they will tend to make you hold on, possibly for the rest of your life!

Answer 4

A/C is more efficent over long distances due to the way it is transmitted. For instance, the voltage of AC can be stepped up fairly easily to over 7K volts, which makes it easier to send a long distance with minimal loss. Also, basically AC shakes electrons back and forth rather than flowing in a constant current, so transmission requires less energy.

Answer 5

Because it is easier to use transformers to step voltages up and down using AC than it is with DC.