The use of electricity has reached enormous proportions. With it, the need to transport electricity over great distances, has also risen.
This was not possible through direct current, which meant loss of power on the way.
Thus, alternating current was introduced, which could be transported over distances at the desired high voltages. This transportation of electricity uses large amount of electricity over thin wires and thus electricity is transmitted at high tension.
Below Electricity High Tension info from Wikipedia (Read More):-
Electric power transmission is the bulk transfer of electrical energy, a process in the delivery of electricity to consumers. A power transmission network typically connects power plants to multiple substations near a populated area. The wiring from substations to customers is referred to as electricity distribution, following the historic business model separating the wholesale electricity transmission business from distributors who deliver the electricity to the homes.[1] Electric power transmission allows distant energy sources (such as hydroelectric power plants) to be connected to consumers in population centers, and may allow exploitation of low-grade fuel resources such as coal that would otherwise be too costly to transport to generating facilities.
http://en.wikipedia.org/wiki/Electric_power_transmission
