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by samwillis 1279 days ago
Unless you are not in North America. Most of the rest of the world have a base voltage of, and all domestic outlets are 220-240.
1 comments

In the US "220V" refers to a high current outlet normally, in a country where household outlets are 220V, you still need a high current outlet and, for safety reasons, most outlets are not high current, just like in the US.
U.K. is 220v @ 13A for an average socket. That's almost double what a common 120v 15A does in the U.S.
In the US it's 30A minimum for an average "220v" (it's actually 240 V) outlet such as a dryer or AC, that's more than double what 13A 220V gives in the UK.
You will not find a 240 in the u.s. outside of specific installations, while in the UK a common plug already is 220 13a.
It depends on what you call "specific installations", in my house I have two 240V 30A outlets for the dryer hookup and for an electric oven and one 240V 40A for the air conditioner.
We are talking of an outlet for a car in winter. It is much more common to have a common outlet outside than to have a 240v outlet. Even if there were a 240, it would be in the nema format that electric vehicles don't accept directly.

This is also the same problem with electric kettles in the U.S. they boil much faster in the u.k. because almost double the power for a common outlet.

Wait, this is terribly confusing. Why would "220 volts" not refer to a completely objective measurement of current?
The Volt is a unit of electric potential. The SI unit of current is the Ampere. You can have very large potential differences (in V) with very small current (in A). The unit of power is the Watt, and 1 W = 1 A*1 V.

So, a given power can be obtained using any voltage, with the proper current. In practice, high currents are unsafe so we tend to avoid that in unprotected sockets. Different norms correspond to different tradeoffs.

The voltage and current combined is the actually important number which is the total wattage available on that circuit. The US standard 220/240V outlet will provide ~30A of current usually while a UK outlet usually has a 13A fuse in the plug matching the circuit's rough availability.
A 220V outlet will always give you more power for the same current limit than a 120V
A 220V outlet won't always have the same current limit though.
True, but in the US most 240v outlets are 30-50A, whereas in countries that use 240v for their normal household outlets, the current limit is usually 13-15A. Still double the wattage of a typical US outlet but not up to the standards of a “Level 2” charger.