You might want to re-think how much time & money you save by measuring out a specific amount of water, especially if you wait there and watch it boil:
It takes me about 5 seconds to pour my coffee cup of water into the kettle and not spill after filling from the tap, so say you take an extra 5 seconds to measure just the right amount of water rather than using the fill line or guessing. If I value my time at minimum wage, that works out to about 2.1 cents it costs me.
Various sources show it takes about 0.12kWh to boil 1 liter of water in an electric kettle, and at a rate of 11 cents per kWh that costs you 1.32 cents. If you take the time to measure out 1/3 of that (one coffee cup’s worth of water) and only heat it, you would save 0.88 cents worth of energy.
So, you “save” 1 cent by investing 2.4 cents worth of time. If you stand there waiting for the kettle to boil you’ll have to invest more like 60 cents to save that penny.
Eh…not really although it is commonly cited…(the video below is long…25 minutes…but interesting and he addresses the voltage bit and shows a kettle on a gas stove is a very inefficient way to boil water…which bums me out because I have a gas stove and a kettle and I like my tea):
I would guess it takes zero extra seconds to measure the correct amount of water, possibly even negative seconds. What you do is take the mug or cup that you plan on using anyway, fill it to the brim, and pour into the kettle. The extra step might take a second or so, but letting the water run for less time saves at least that much time.
I would probably agree with this (or something along these lines). I’m thinking of the typical situation where you’re on the scene anyway. In that situation, you save time by having less water, taking less time to boil.
I think you’re kidding here, but yeah it’s impossible to take negative time to do something. And no need to guess, I actually did time how long it takes me to pour my coffee cup into the kettle just for this response. You could maybe get around the extra time by drawing your own new fill line, but you’re so close to the bottom of most kettles it’ll be about 1/4 inch deep and take just as long in fussing to make sure you didn’t over or underfill.
I get the idea of trying to be efficient, and have the same bug myself. But I find it easy to slip into diminishing returns when one gets down to trying to save fractions of pennies.
I’m not kidding. It takes negative extra time, meaning that it’s faster to do it exactly than fill it to the minimum line, using the method I described.
Money is not the main issue. Time is the main issue. If you have twice as much water as you need, then it will take longer for the kettle to heat up, which can be inconvenient. But if there’s also no real reason to put in so much water anyway, then the money is also a minor issue as well.
If filling it up to the min line works for you, then by all means go for it. I think less is better, and my question in this thread was whether this would ruin anything. Sounds like it won’t.
In part, but your average US outlet is a 20A 120V outlet, for a maximum of 2400 watts. Your typical British one is 13 A 230V for 2990 watts. So there’s a bit more juice that can be fed into that British teakettle.
Which they take full advantage of; your typical US electric teakettle is a 1500 watt rated device, while a lot of the ones on UK Amazon specifically list themselves as 3kw “fast boil” units.
Dougal: Ted, what would happen if I turned on the kettle without putting any water into it?
Ted: Well Dougal, I’d imagine it would blow up and you would be picking lumps of metal out of your face for the next three years. Your face would become all blotchy and you would get some kind of fish lips.
Dougal: Like Father Bigley?
Ted: Exactly like Father Bigley!
Dougal: Maybe that’s what happened him.
Boah, you get 20A from your tiny 120V outlets in the USA? Did not expect that much, I stand corrected, technically. Still, the Brits are faster. OK, good for them.
Depends on the particular circuit, but yeah, 20 amp outlets aren’t uncommon. In fact, most kitchens have at least two 20 amp outlets. I was wrong when I said “average”- more like some are 20 amp, and some are 15 amps.
I think it’s probably just a cultural difference; a 2400 watt electric teakettle would boil water a lot faster than the standard US 1500 watt one, but most US people just use a regular kettle and the stovetop, so there’s not much market for it. Plus, Americans don’t have the same tea drinking culture that the British do either.
I hardly dare to mention that I do have an electric kettle too, and it has several buttons with different temperature pre-settings: 50°C, 70°C, 80°C, 90°C and boiling. I don’t believe it is too precise, but it feels about righ-ish, for the different green teas my wife has tought me to appretiate. Anyone care to explain how that is regulated?
It heats fast, BTW. It has a min. fill line too, and a max. at 1,750 ml, for whatever that is worth.
An ex flatmate of mine killed a kettle by boiling it dry and I know it happened at least once when I was a kid. “It dries out the element,” is what we’re all told in the UK, including those of us who have no idea what “the element” mean when we’re told this we’re six years old and making a cup of tea.
Kettles here do switch off automatically, but it doesn’t mean they can’t get burnt out. The smell of “the element” being burnt out was very metallic and unmistakeable.
I guess it’s the same as if you put a dry pan with a thing base on a hot heat and left it there - it’d end up burnt.
FWIW, Voltage in the UK is usually actually 240v, not 220. I don’t suppose it makes an awful lot of difference, but its not nothing. It can run at 220v but the standard is still 240.
As the above cite says, it was standardised to be 220v to comply with most of Europe, but in practice that made no difference (it became 220-240 volts rather than 220 volts only).
For kettles specifically, it’s not just that the supply will be 240v, but the plug for the kettle will also be 240v if you buy it in the UK.
Likewise, the US is 120 V, but for some reason most say it’s 110. I suppose because after voltage droop, it’s usually something like 117 by the time it gets to the device, and that gets rounded down to 110.
Backpackers have long recognized this problem and for a while now you’ve been able to get kettles with a heat exchanger built in. They claim to increase efficiency by 30-50%, which is about right in my experience. I suspect that a model built for a kitchen range could do even better due to not having mass as a constraint.
The solution to the minimum fill level being too much water for one cup is to get a larger cup. I make my coffee into a 16oz cup, which is close enough to the minimum level of 0.5 liters to not matter. Fill the kettle to minimum, prep my coffee, and by then the kettle’s done, and it’s time to pour.
I recently had to replace my kettle because a plastic pin broke that was involved in the complex mechanism designed to only let the kettle turn on if the lid was closed. That kettle definitely had a steam tube to turn it off after the water boiled.
I thought that the reason for the fill line was very simple: the heating coil needs to be covered with water. I’ve seen electric kettles with minimum fill lines, and without. The ones with minimum fill lines have a visible metal coil and the fill line is around 1/2 above the coil. The ones without fill lines have a flatter heating element at the bottom of the kettle.
Some years ago we emptied out the hot water heater (long story) and turned it on again before refilling it, which killed it because the coil wasn’t covered with water. Our plumber, a recent Irish immigrant to the US, said to think of the hot water heater as a giant electric kettle.
In North America, typical household outlets are 15A 120V. Some are 20A but those have funny plugs - one pin is at right angles to the other, not parallel. They are more likely found in kitchens or other places where heat appliances are common.
Most kettles, toasters, hair dryers and similar are between 1000W and 1500W (My kettle is 1500W, my 2-slice toaster 850W) Code says a circuit should not deliver more than 80% of it’s rated power continuously, so 80% of 15A is 12A; rounding up 1440A an appliance should not be more than 1500W unless it has that funny 20A plug. My house, built in the last 15 years, has no 20A plugs.
Using the same logic for UK, as mentioned above, 13A*80%*240V = 2496W. I assume 13A/2500W is for special applications like our 20A? What’s a standard outlet? (10A ===> 2000W ?)
I assume a kettle needs a certain level of water to ensure the heat is carried away from the element as fast as it is generated, especially once some of the water is turning to steam; the convention process only works so well with a thin layer of water, so a certain depth is needed.
