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Comment by iyulaev | Hacker News Reader

Absolutely right. I was using 120V as shorthand for "the 120V/20A circuit that we're all used to."

I don't think saying "120v isn't enough, you need to rewire your entire house" is really accurate either. Most water heaters, stoves, and some central heaters run off a merged breaker for 240v. You can easily use one of those lines for the car if you don't plan on taxing the thing the entire time (though I figure if you have 50k for a car you have 1k to add an extra circuit and wire your garage up for it).

Yes, although at least in my view part of the selling point is that we have plugs everywhere, so you have electricity anywhere right? Well, hunting around for a 240V plug is a big harder than 120V.

Also, even though 99% (???) of the world is on 240V, I think the current rating on those circuits still limits power to around 2kW sustained.

I'm in Australia, and our power supply is 230V AC (+/- 6%) (240V was the standard before 2000, but is still within the acceptable limits). Most power outlets are 10A (max ~2300W) but I also have two 15A sockets in my house for the air conditioners (3450W - I also use one to power my coffee machine, which pulls 3200W when warming up!), and could theoretically get a 20A socket (4600W) installed. With an industrial outlet, you can get single phase power of up to 32A (7360W), but I doubt most electricians would install that for you at a house.

Oddly enough, I've got a 32A socket hooked up to a water pump. I'm not entirely sure why the electrician installed in, there's no way the pump draws more than an ampere or two.

Thanks for explaining the 240/230v difference, I'd always wondered why it existed.

And some parts of EU still actually have 220V. There's no major practical difference between 220V/230V/240V, it's just that different parts of the world came up with slightly different standards. As standardization has progressed, now all of EU is on a nominal 230V ± 6% 50Hz -- in practice the countries are still supplying their old voltages. 230 is presently 220 in Hungary and 240 in UK. Since both are within the mandated 6%, this doesn't cause problems. Eventually, as parts of the grid are serviced and replaced, it will be transformed into unified 230V.

Also lot of electronics nowadays uses switched-mode supply so it doesn't really matter all that much.

Seriously? Which machine is that?

It's not that amazing. Any decent $60 kettle in the UK will do 3000W these days http://www.amazon.co.uk/s/ref=nb_sb_noss_2?&field-keywor... (viz. the electrical consumption surges during TV ad breaks http://news.ycombinator.com/item?id=5018560 ).

It's a used commercial 2 group machine. I got it for less than $1000 and it makes better coffee than the $2000-$3000 automatic domestic machines in the shops.

It is a little cumbersome though (had to plumb it to a tank, etc)

A bit like this one: http://www.cafeideas.com.au/product.asp?pID=3620&cID=211

Not bad! I'm after an espresso machine myself in Sydney. Never thought of looking for ex-commercial stuff.

I'm in Scandinavia, and our standard household circuit is 10A@230V for 2.3kW.

But when you need a lot of power, you would install a 400V three-phase circuit (230 V between one phase and ground, 400V between two phases), something like this: http://en.wikipedia.org/wiki/Industrial_and_multiphase_power...

This kind of circuit isn't very common in households, but it's fairly simple to get one if you need it - most houses have three-phase power right up to the door, so an electrician can install it in a few hours. My grandfather had one for his circular saw.

But yes, hunting for these circuits on a road trip will be harder than finding a household circuit. Although that could change rather quickly if electric cars prove popular.

> I'm in Scandinavia, and our standard household circuit is 10A@230V for 2.3kW.

Only 10A? That seems very low, the common "mainland" circuits seem pretty much all rated 16A (@230V). So you can't even run some electric kettles at your place?

(but I confirm you can get 3-phase for very high loads, you'll usually pay the electricity company through the nose for running it though)

I think the older standard was 10A circuits for most of the house, 16A for kitchen and washing room and a dedicated 20A for the electric stove. I thought 10A was the most common still, but I may be wrong there.

The standard for newer houses, the past 10-15 years or so, is indeed 16A. I have 5x16A + 1x20A and a 35A main circuit breaker, so I can pull about 8kW all together. Enough for a few kettles :) (This is for a a 40m^2/400 sq.ft. condo. A house would have more circuits and a larger main circuit breaker. And this is for Norway - we tend to follow similar standards as Denmark and Sweden, but there may be differences I'm not aware of.)

> I think the older standard was 10A circuits for most of the house

Ah that's probably it, I missed that you were talking about older houses. The content of your second paragraph sounds much like what I know.

In Australia 240v @10A is a atandard household circuit, and dryers etc. run on 240V 15A circuits. (I believe 400V is obtainable as per the GP but I haven't lived i Australia for a while.)

Netherlands mostly runs on 16A@230v wiring/breakers, coming to 3.6kW. At least for the last 20 years (kind of important for at-home lanparties :) )

Also, 240v cars makes so much more sense in a world where 99% of people use 240v outlets, and in the US you can just oscillate two 120v's and get a usually-good-enough 240v signal.

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