My mate just moved from NZ (230 volts) to Canada (110 volts) and he reckons the electric kettle over there is basically impotent due to having less than half as much potential kicking about in the wires.
Maybe that explains why the Americans are so attached to their boiling pots?
There's no reason why a 110 V kettle couldn't be as powerful as a 230 V one, if it was designed for that voltage. Just like light bulbs in the US are not generally less bright than those in France.
If you take a 230 V kettle and connect it to 110 V, then yes it will be less powerful. Perhaps about 1/4 of the power.
If volts were there only limitation on the design that would be correct, however amps are also important in this case. A 240V UK wall socket can be up to 13 amps whilst a US 110V line is 12 amps.
With power (watts) being volts * amps that gives the power of 3120 Vs 1320 watts for UK Vs USA respectively.
This means a UK kettle can dump heat into the water up to 2.4 times faster so should boil in less than half the time.
Kettles are at the high end of power consumption as generally people want a fast boil. Lights are towards the low end as its rare for someone to want even 1000 watts of incandescent brightness.
In Europe kettles typically use around 2300W, since homes are typically wired with 16A breakers (and you don't want the kettle to pop the breaker as soon as you add another device). But US homes are wired similarly, typically with 15A breakers. So you get kettles that typically use 1500W, much less than the European equivalent.
Sure, you could use powerful kettles in the US on a 20W outlet, or on a 230V circuit, but nobody is going to do that. A typical kettle that you can just buy and plug in wherever is less powerful in the US just because you use halve the voltage but don't wire for double the current.
Ok, that makes sense! I guess I just assumed that US wiring would typically be rated for higher currents to compensate for the less efficient transmission.
It didn't occur to me that Americans would settle for having less power than the rest of the world, it seems uncharacteristic somehow :)
We choose wiring gauge mostly by the "how large can it be while still moving well inside a wall?" factor. So, it's not surprising different places use the same one.
I'm sure 1% of Americans have 30 amp circuits in their kitchen and the help can boil water at twice the rate. Most Americans support this because they consider themselves just temporarily embarrassed by low-powered kettles.
Same here (in Poland). Besides being faster, this is likely more energy-efficient, as the kettle isn't bleeding heat as much as a pot on the stove.
Speaking of which, I don't understand why we've settled on a gas stove design that's so terribly inefficient, with most[0] of the heat leaking around the pan. Why no design with a combustion chamber of some sorts?
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[0] - Well, at least a lot. I didn't do the math here yet, but it's hard to imagine otherwise with unrestricted airflow around the pan.
> Why no design with a combustion chamber of some sorts?
Thermal capacity. Gas stoves are great because they have none, so any temperature changes are immediate. Anything between the pot and the flame will destroy that advantage.
Also, the combustion chamber will have a vent for the exhaust. So I would suspect that it won't be any more efficient, except for very small pot sizes.
Induction cooking plates are the same (with magnetic pots, pans and so on, otherwise won't work(at all)), regarding the immediacy.
When I got my first, I've been curious and experimented with water. Depending on the model they have sensor buttons where you can raise/lower the temperature in 10 to 20°C steps.
Mine have 10°C steps, where with water in a pot at 90°C the first few small bubbles start to rise, like in soda/mineral water. When at 100°C the big boiling bubbles start after about 2 to 3 seconds.
Mine are rated at 2500 Watts each, have segmented induction coils where the outer segments switch off with smaller pots, are plan like a mirror and thus very easy and fast to clean.
> Also, the combustion chamber will have a vent for the exhaust. So I would suspect that it won't be any more efficient, except for very small pot sizes.
The airflow needs to be there, but I imagine it could be slowed down, so that the hot air spends more time transferring energy to the pot. That would retain the fast reaction time, and let one burn less gas for the same amount of cooking output.
Specialized hiking gear typically come with integrated heat exchangers and insulation to be more efficient when used on gas-fired stoves. This makes them really good at boiling water, and terrible at anything else since it's impossible to control the heat in any meaningful way.
Be that as it may, it's most likely more expensive. This is purely my personal guesstimate, but gas tends to be much cheaper in Poland than electricity. More efficient, maybe, but I'd be very surprised if it was cheaper given the prices.
Yes, I assume it's more expensive. Gas is cheaper than electricity in Poland, but then again, electricity also isn't that expensive for preboiling in a kettle to make a big difference.
On a related note, I was surprised when I did calculations on how much it actually costs us to bake our own bread. We started doing that a lot during this pandemic. It turns out, the cost of ingredients + electricity adds to slightly less than what it would cost to buy the same products from a bakery. This doesn't price in time spent on preparing and baking, but it's not like we could actually use that time to make money, we're having fun, and going to a store also takes time (and/or fuel). Electricity is cheap.
Certainly that's true (although when I got an induction stove i only had to replace one pan - they've been widespread for long enough now that all the cookware I bought in the last decade is compatible, as are all my ancient cast iron pans).
It's worth understanding though - at least in the UK the received wisdom is that "kettle is fastest" - but that's not always true any more.
Tangent: In the UK, I boil any water I need in a 240 V kettle. It dramatically reduces the waiting time.