why does uk use more voltage than usa?

The first public power system was owned by Thomas Edison, and operated at about 50 volts DC. Because you can't transmit DC over long distances, he conceived a system with a coal fired power station at the end of every street...Cough Cough!

Then along came George Westinghouse with a plan to use AC, which would destroy Edison's DC system. A major fight ensued, with Edison claiming that AC would be far too dangerous to be used in homes because it would permit the use of higher voltages.

The dispute was finally settled by Westinghouse using a fairly harmless low voltage on his AC system.

During the dispute, all the stray cats in Menlo Park disappeared as Edison used them to research the lethal effects of electric shock.

I think the USA changed from DC to AC long before the UK and tried to keep the AC voltage in line with the original DC voltage.

Therefore the UK realised that the lower voltage of 110v single phase to neutral and 3 phase 220v was less economical and opted for 3 phase 415v with phase to neutral of 240v.

240v being considered a "happy medium" between economy and safety.

110v to earth can still kill you, just as much as 240v given the right conditions.

That's 110-120 Volts, vs. 220-240 Volts, nominal. (Not Watts.)

Electrification took place in the U.S. first. When the U.K. (and most of the rest of the world) standardized their electric utilities, they learned from the U.S. experience. One lesson learned was that 110-120 Volt power was inefficient. Another lesson was how to build a 220-240 Volt system that was still safe for household use.

Short answer: The U.S. system is "electricity 1.0". The U.K. system is "electricity 2.0".

110 volt is more safe for domestic appliances.But when voltage is low we have to use more thick wire which is costly Many countries use 230 volt for domwtic supply as standard..

Economy through losses reduction, and lighter wires for the 220 V system, but more stringent safety measures to be taken.

When different countrys selected the standard household utility voltage, there were no global standards. After they were chosen, it would have been too big a deal to change.

first....volts not w

for a similar power device ...in UK , passing current is less than in USA so its wires are thinner than in USA .....cheaper ....but in the USA risk of electric shock is less than UK ....usually no death ...

http://en.wikipedia.org/wiki/Electric_power_distri...