EE: Supply system?

Power of a transformer is VI. If V is increased then I becomes small. The energy loss I^2/R(resistance of the wire ) becomes small. You can transmit the power for a long distance. You can use the same for house hold items as the shock is proportional to the voltage. You need very low voltage values for appliances.

As the voltage is increased the distance between lines must be increased to prevent flash over from line to line. As the current is increased the line size must be increased to reduce resistance. It is much more efficient and cost effective to use smaller wire and increase the distance between lines. Voltages can be increased to 1 Million volts for very long lines and stepped down to usable levels at the destination.

IT BASES ON THE DISTANCE BETWEEN POWER SOURCE AND COMSUMMER TO OVERCOME THE TOTAL TRANSMISSION LINE RESISTANCE.

Tesla gave us that Idea in that higher voltages are less effected by resistance in transmission lines and deliver more power at a distance.

We use higher voltages for power transmission because to deliver a given amount of power, current = power / voltage, and the power lost due to resistance of the transmission line is current^2 * resistance. For safety reasons the voltage is stepped down when it reaches homes, offices and other places where people use electricity.