Why is Electricity Transmitted at High Voltage and Low Current

Generally we get electrical power from a Power Station and of course, there is a minimum possibility that it will present near to our home. So it travels a long distance to come to our home. We use several types of power transformer to transport the required power to our home or industry.

High Voltage Line
High Voltage Line

You can read this article “How electricity comes to our home” and you will get a clear idea about the transmission and distribution system of electrical power. In this post, I am going to discuss “why we use high voltage AC (Alternating Current) power on a transmission line?”

Related: Three Best Sources of Renewable Energy

Electricity Transmitted at High Voltage and Low Current:

For getting power from the Power Station it required various types of power transformers and it operates on high voltage like  11 KV, 33 KV, 66 KV, 110 KV, 132 KV etc. 1 kV (Kilo Volt) is equal to 1000 volts. Which means you will get 132,000 volts stands on 132 KV transmission line.

Many countries in this world are currently used up to 765 kV in electric transmission linesNormally the transmission line above 33 kV is used. 33 KV or below voltage line is used to call the distribution line.

Now first of all, How do we transport AC at such a high voltage?
According to the power equation, P = VI (Where, P = Power, V = Voltage, I = Current).

By this equation, we can say the total amount of power is equal to the voltage and current. Now if we increase the voltage by reducing the amount of current then the total power will always be the same.

Now come to another point. Usually, the current flow depends on the area of the cable. If you want to transport a low amount of current through a cable then the area of the cable can be used less. If the area of the cable is less and no matter which types of cable conductor then the cost will be less. Now if you can use more voltage and less amount of current through the cable in the transmission line then the cost of transmission cable will be less.

If in transmission line amount of current flow is less then the transmission line will not be heated so that the copper loss will be less and it will reduce the line to line voltage drop. Considering these types of matter in the transmission line, we increase the voltage by decreasing the current.

Related: Fundamental of Electric Power Distribution System

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