Yes, that is a reason in favor of low voltage DC. However, there are a zillion other, better reasons to use AC.
Actually, in a modern household where the majority of devices are relatively low power and don't have a motor, DC would be more efficient than AC and work just fine. The main advantage of AC is the ease of dropping from higher to lower voltage when going from transmission to local distribution, or for running motors efficiently. When 90% of the stuff in your house is running on 5VDC, 120/240V AC is wild overkill. At high voltages AC does have the advantage that it doesn't lock up your muscles if you get current running through you, so it's slightly safer at an equivalent voltage.
You'd still need something high-power (and probably AC, though DC could work) for your vacuum or hair dryer, but for most other things these days modest-voltage DC would work well.
Talk about a little knowledge can be dangerous! As previous posts have said, voltage doesn't kill it's the current. Look at police tasers as an example. Second, Japanese voltage is 220v just like Europe so it's no surprise.
The most accurate thing to say would be that BOTH kill, and only when it goes to the right place in your body. That's why tazers fire TWO darts, with the intent being that the current doesn't go through your heart. And why people shot in the chest near the heart sometimes die--the current ends up going through their heart and kills them, particularly if they had something wrong to begin with.
Japan, by the way, is NOT 220V--it's the lowest in the world at 100VAC. The west half of the country is at 60Hz and the east at 50Hz, which is bizarre, because it has two separate grids and appliances with AC motors in them can't be moved from one half of the country to the other and still work properly.
Japan's real issue, though, is that most of the country is still wired with non-polarized 2-prong outlets, which is completely insane for anything bigger than a power brick.
The things everyone forgets is the amps. Europe and the US both output a similar amount of power. Europe has double the volts but half the amps. That gives you the same amount of watts.
Right, which is why I said that you save copper in the walls in Europe vs the US's 120V household wiring--lower current equals thinner wire (or less wire loss for the same size wire).
And I'm also aware that in most countries with 220V the outlet design is safer (like UAE style in the photo earlier with the doors in the prongs, the individually shielded pins, and switches on each outlet). Still, things can and do go wrong. Which is what GFCI is for; I did not realize GFCI was a requirement on all circuits in some European countries (just on ones exposed to water in the US--kitchen, bath, outdoor), although I can see why you'd do that--it's the only thing that's going to make it safe.
Seems like it would be a pain with inductive loads, though, since those have a tendency to trip GFCI breakers.
laptop (not sure if still true for the current line).
