(N/A) Transformers are essential for the large-scale transmission and distribution of electric energy over long distances.
The voltage output from the power generator is stepped up using a step-up transformer. This increase in voltage results in a corresponding decrease in current for a given power level $(P = VI)$,which significantly reduces the $I^{2}R$ power loss (heat loss) in the transmission lines.
The high-voltage electricity is then transmitted over long distances to area sub-stations located near the consumers.
At these sub-stations,the voltage is stepped down to safer levels. It is further stepped down at local distribution sub-stations and utility poles before a standard power supply of $240 \ V$ reaches our homes.