this was the best link i could find to describe it... maybe we should go into business with this one wire concept and undercut the big utilities...
http://www.elec.canterbury.ac.nz/ME...%20African%20rural%20electrification.htm

i copied this from a conversation 6 years ago:
"You may not believe this, but in many parts of rural Alberta (Canada) there are single phase AC systems which run with one (1) wire only. The AC neutral is (you guessed it) the Ground. Line voltages are typically 14.4 kV for such systems."

and this link was ok too..... i copied the SWER section below
http://www.holec.com.au/references/basic_elec_theory/distribution_systems.html

SWER Two or Single Wire System (Single Phase)

This system uses one phase of a three-phase system but the return path is via the earth. One side of a transformer primary winding is connected to the active conductor and the other side is connected to earth. These systems are connected to the 22kV and 33kV systems. This means the single-phase transformer voltages on the primary side of the transformer are 12.7kV and 19.1kV respectively.

In Western Australia an overhead earth is used so it is a two-wire system, in other states only the active is on the pole and the ground is used as the return wire.

The return current path goes through the ground or the earth system. A poor or missing earth connection can prevent the flow of current even though the system is still alive. This is true for all circuits, and highlights the need for care when working near system earthing equipment.

Lethal high voltages can exist across a poor or broken earth conductor.