Joined: 14 September 2010
The voltage level will largely depend on the power that is being distributed.
The greater the power, the higher the voltage used. This is due to the efficiency gained at higher voltages; both from a reduction in voltage drop, and power losses (I^2 R losses).
Some back-of-the-envelope calculations will quickly show you what voltage levels are required as the power increases.
It is common to distrubute power around primary grid sites at 33 kV; then at 11 kV to primary substations where it is then distributed at LV to consumers.
Edited: 03 May 2013 at 05:35 PM by Zuiko