# Are 110v electric kettles too slow? **URL:** \ **Category:** Factual Questions\ **Created:** [February 7, 2004, 10:39pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040 "2004-02-07T22:39:56Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![amarone](https://avatars.discourse-cdn.com/v4/letter/a/e0b2c6/32.png) [@amarone](https://boards.straightdope.com/u/amarone)\ **Post date:** [February 8, 2004, 3:46pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/21 "2004-02-08T15:46:37Z")
> [@missbunny](#): > > I don’t think my electric kettle holds 1.5 liters so I cannot participate in the experiment. I only asked for 1l or 35 fl. oz. ---
**Author:** ![MsRobyn](https://avatars.discourse-cdn.com/v4/letter/m/90ced4/32.png) [@MsRobyn](https://boards.straightdope.com/u/MsRobyn)\ **Post date:** [February 8, 2004, 3:49pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/22 "2004-02-08T15:49:02Z")
My electric kettle (Cuisinart from Canada. No voltage/wattage on the label, and I don’t care enough to dig the book out.) boils 1.75 liters of water in about five minutes, give or take. And FTR, I have an electric kettle because it’s safer around a tall, active toddler with an incredible reach. Robin ---
**Author:** ![robo99](https://avatars.discourse-cdn.com/v4/letter/r/a8b319/32.png) [@robo99](https://boards.straightdope.com/u/robo99)\ **Post date:** [February 8, 2004, 3:49pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/23 "2004-02-08T15:49:02Z")
> [@amarone](#): > > My kettle, bought in the US, is just like the ones in the UK. It is cordless, jug-style, with a lid and a switch. It is made by Krups. Well, obviously it’s an issue of marketing. I even had to order my crappy kettle over the internet. ---
**Author:** ![Mops](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mops/32/16494_2.png) [@Mops](https://boards.straightdope.com/u/Mops)\ **Post date:** [February 8, 2004, 4:46pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/24 "2004-02-08T16:46:00Z")
> [@Yeah](#): > > … > In the 1970s, when I lived in California, I installed a European style, high wattage outlet on the kitchen wall connected to the 220V outlet that supplied the electric range. > … “European-style, high-wattage”? I’d have assumed US domestic wiring would be designed for high loads. The circuits for electric outlets that I have come across in Germany are usually protected by a 16 A or (less frequently) a 10 A circuit breaker, i.e. they can power a 3.68 kW or 2.3 kW resistive load, respectively. What’s the usual fuse rating in the US for such a circuit? ---
**Author:** ![Stormfield](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@Stormfield](https://boards.straightdope.com/u/Stormfield)\ **Post date:** [February 8, 2004, 6:13pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/25 "2004-02-08T18:13:34Z")
> [@tschild](#): > > What’s the usual fuse rating in the US for such a circuit? Branch circuits in the US are generally connected to a 15 amp or 20 amp circuit breaker, so, assuming a line voltage of 115, the circuit capacity would be 1725 watts or 2300 watts, respectively. Higher power appliances, such as a range, are connected to a 230 volt circuit, and protected by a 50 amp circuit breaker, giving a capacity of 11.5 kW. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [February 8, 2004, 8:35pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/26 "2004-02-08T20:35:37Z")
> [@amarone](#): > > My kettle, bought in the US, is just like the ones in the UK. It is cordless, jug-style, with a lid and a switch. It is made by Krups. Where did you get it? Those “Electric Dispensing Pots” look rather nifty. Do they use up a lot of power, and can you just turn one up to produce swiftly boiled water? ---
**Author:** ![TheLoadedDog](https://avatars.discourse-cdn.com/v4/letter/t/35a633/32.png) [@TheLoadedDog](https://boards.straightdope.com/u/TheLoadedDog)\ **Post date:** [February 8, 2004, 11:38pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/27 "2004-02-08T23:38:10Z")
Kambrook “Esprit” (cordless) 240v - 2200W : 2 minutes 42 seconds ---
**Author:** ![Popup](https://avatars.discourse-cdn.com/v4/letter/p/94ad74/32.png) [@Popup](https://boards.straightdope.com/u/Popup)\ **Post date:** [February 9, 2004, 12:29pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/28 "2004-02-09T12:29:50Z")
> [@dutchboy208](#): > > There’s something else we’re missing here- limescale buildup can affect boiling times for electric kettles quite dramatically. Is that really so? I have tried to investigate this a bit, and my conclusion is that even heavy limescale buildup has insignificant effect on the thermal output. Most modern kettles use a MIMS design ( mineral insulated, metal sheathed), where a thin wire made out of a high resistivity metal, such as Kanthal, is surrounded by an electrically insulating oxide, typically MgO. Outside all this you then put a metal sheathing, often stainless steel. [sub](Thank you **Desmo**!)[/sub] All a scale builtup would cause, is to add a secondary insulating layer. Assuming a fixed power, the energy has to dissapear somewhere, and I believe that almost all of it will go through the limescale. The net effect is that the heating element heats up a bit more, but the resistivity of Kanthal is fairly constant, so there will be no change in emitted power. ergo, the assumption above was correct. > [@](#): > > _Rival switchless model SK61 (120V/ **1000W** ) boiled 35 fl. oz. from the cold tap in 3 minutes and 19 seconds. > [snip] > I’m fairly confident this thing would have turned out boiling water in under two and a half minutes had it been clean. Hardly, if at all, slower than a UK 240V model. **Isn’t it the wattage that makes the difference anyway?** _ Yes. it’s inded the wattage that counts. And your machine puts out a measly 1000W, whereas most european 230V[sup]_[/sup] kettles pump out about 2 - 2.5kW. (Except of course **GorillaMan** s 3kW monster. I want one of those!) [sup]_[/sup]UK used to have 240V, and the continent 220V, but since more than a decade it has been harmonised, and it’s now (supposedly) 230V all over Europe. ---
**Author:** ![Rayne\_Man](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@Rayne\_Man](https://boards.straightdope.com/u/Rayne_Man)\ **Post date:** [February 9, 2004, 12:52pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/29 "2004-02-09T12:52:43Z")
I have been trying to find out what is the energy saving and efficiency of using an electric kettle as apposed to a stove top kettle. I havn’t been able to find actual figures but ( via Google) I have found several agencies, both government and power companies that all say the same thing. This is " an electric kettle is the most efficiant way to boil water compared to a stove kettle or a microwave" . I suppose the actual saving would depend on the comparitive costs of gas and elecricity. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [February 9, 2004, 12:59pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/30 "2004-02-09T12:59:42Z")
> [@Popup](#): > > Is that really so? I have tried to investigate this a bit, and my conclusion is that even heavy limescale buildup has insignificant effect on the thermal output. Most modern kettles use a MIMS design ( mineral insulated, metal sheathed), where a thin wire made out of a high resistivity metal, such as Kanthal, is surrounded by an electrically insulating oxide, typically MgO. Outside all this you then put a metal sheathing, often stainless steel. [sub](Thank you **Desmo**!)[/sub] All a scale builtup would cause, is to add a secondary insulating layer. Assuming a fixed power, the energy has to dissapear somewhere, and I believe that almost all of it will go through the limescale. The net effect is that the heating element heats up a bit more, but the resistivity of Kanthal is fairly constant, so there will be no change in emitted power. ergo, the assumption above was correct. But the more a conductor is insulated, the less power will be lost to resistance, right? It isn’t as if the heating element turns _all_ the juice coming through it into heat; some makes it all the way around, surely? ---
**Author:** ![Popup](https://avatars.discourse-cdn.com/v4/letter/p/94ad74/32.png) [@Popup](https://boards.straightdope.com/u/Popup)\ **Post date:** [February 9, 2004, 1:14pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/31 "2004-02-09T13:14:14Z")
> [@dutchboy208](#): > > But the more a conductor is insulated, the less power will be lost to resistance, right? Wrong! (As long as the insulator is _outside_ the path of the current) The amount of electrical energy that will be converted to heat is simply **P=U \* I** , or (with U=R\*I), **P = U[sup]2[/sup]/R**, where: P = total power (measured in Watts) U = Voltage (measured in Volts (230V in Europe, 110V in US) ) I = Current (measured in Amperes), depends on the resistace and voltage R = Resistance (measured in Ohms) Almost independent. There is a very slight increase with very high temperatures, but that is insignificant for this discussion. (At least for the kind of metals we’re using). So, the total power only depends on the Voltage and the resistance. The only thing which will happen if there is a really thick limescale buildup around the coil is that it will act as a thermally insulating layer, so some of the heat which comes from the coil will remain inside, bringing the temperature of the coil up a little bit. Soon, however, it will reach a steady-state, and all the created energy will come out to the water. So, yes, in theory, there will be some eergy lost, in the heating up of the coil, and (possibly) a slightly increased resistance, but these factors are very, very small, and can not be observed in your home. > [@dutchboy208](#): > > It isn’t as if the heating element turns _all_ the juice coming through it into heat; some makes it all the way around, surely? Nope! All the energy in the electricity is ‘liberated’ as it passes through the resistor. ---
**Author:** ![Capt\_B.Phart](https://avatars.discourse-cdn.com/v4/letter/c/9fc29f/32.png) [@Capt\_B.Phart](https://boards.straightdope.com/u/Capt_B.Phart)\ **Post date:** [February 9, 2004, 2:59pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/32 "2004-02-09T14:59:11Z")
> [@GorillaMan](#): > > 240v 3000w Morphy Richards…2 minutes 20 seconds. What do I win? 😃 Ha! You must have the same model as me (I timed mine as 2 Mins 15 secs) noisy thing - but quick ---
**Author:** ![Running\_with\_Scissors](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Running\_with\_Scissors](https://boards.straightdope.com/u/Running_with_Scissors)\ **Post date:** [February 9, 2004, 3:51pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/33 "2004-02-09T15:51:56Z")
> [@Stormfield](#): > > Branch circuits in the US are generally connected to a 15 amp or 20 amp circuit breaker, so, assuming a line voltage of 115, the circuit capacity would be 1725 watts or 2300 watts, respectively. True, however, you’d be hard pressed to find **any** kitchen appliance (particularly an inexpensive portable one like a kettle) drawing more than 15 amps at 120 volts. 20 amp circuits are generally used in kitchens to allow you to run more than one high wattage appliance (say a microwave and a toaster) on the same circuit at the same time. A plug for a 120V 20 amp appliance would be different than that for a 15 amp (they’re similar, but the two blades are perpendicular to one another on a 20A rather than parallel on the standard 15A), which is why one slot in a 20 amp outlet is T-shaped, allowing both 15 and 20 amp plugs to be used in it. ---
**Author:** ![amarone](https://avatars.discourse-cdn.com/v4/letter/a/e0b2c6/32.png) [@amarone](https://boards.straightdope.com/u/amarone)\ **Post date:** [February 9, 2004, 11:39pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/34 "2004-02-09T23:39:32Z")
> [@dutchboy208](#): > > Where did you get it? Macy’s, I believe. You can also get them at [Amazon](http://www.amazon.com/exec/obidos/tg/browse/-/10703471/ref=br_bx_c_2_1/102-9284388-6867353). ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [February 10, 2004, 2:34am UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/35 "2004-02-10T02:34:20Z")
Hey! I love a distributed science project. 🙂 I’m in Edmonton, where (as of yesterday when my friend and I had the equipment and need to test it), Voltage is 120AC +/- 1%, at ~59Hz (don’t ask **me** why). We’ve got a 1500W electric Kenmore kettle that turns off when it’s done. And lemme tell you I’m glad about that, as it’s never taken so long as today when I hung around for it. 5 minutes, 25 seconds for 1 litre! We’ve got a slower kettle than even **MsRobyn** ☹ Despite the extraordinary use this kettle gets (2 large pots of tea per day (the parents are UK immigrants from way back), 2 large mugs of chocolate/coffee for me on top of the tea…it’s cold here!) I can’t say this is much of an issue. By the time you’ve finished doing virtually anything else, the kettle is done, so how long it takes becomes moot. If anything needs to be sped up, it’s the time that teabag takes to steep. I don’t want tea 10 minutes from now, I want it now! :mad: 😉 Oh yeah, and virtually all the stove-top kettles I’ve ever seen around here are made by Coleman for taking camping. Or perhaps all my friend just have electric stoves. ---
**Author:** ![MsRobyn](https://avatars.discourse-cdn.com/v4/letter/m/90ced4/32.png) [@MsRobyn](https://boards.straightdope.com/u/MsRobyn)\ **Post date:** [February 10, 2004, 3:27am UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/36 "2004-02-10T03:27:57Z")
> [@Nanoda](#): > > We’ve got a 1500W electric Kenmore kettle that turns off when it’s done. And lemme tell you I’m glad about that, as it’s never taken so long as today when I hung around for it. 5 minutes, 25 seconds for 1 litre! We’ve got a slower kettle than even **MsRobyn** ☹ Eh. I kinda like the set-it-and-forget-it nature of my kettle. It’s rare that I need boiling water Right. This. Instant. When I hear the switch go off, my water’s ready. Robin ---
**Author:** ![Barbarian](https://avatars.discourse-cdn.com/v4/letter/b/e19adc/32.png) [@Barbarian](https://boards.straightdope.com/u/Barbarian)\ **Post date:** [February 10, 2004, 5:21am UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/37 "2004-02-10T05:21:26Z")
Interesting test. I’m an expat Canuck living in NYC, so I have access to both a frequently used electric kettle (Superior) and a gas stove, although I don’t have a kettle for the stove, as you’ll see why. Just filled 'em both up with 1 L of H2O, and the kettle boiled in 3 min 40 seconds. The saucepan has been going for 6 minutes 30 seconds and is just starting to bubble up to a rolling boil. ---
**Author:** ![amarone](https://avatars.discourse-cdn.com/v4/letter/a/e0b2c6/32.png) [@amarone](https://boards.straightdope.com/u/amarone)\ **Post date:** [February 11, 2004, 11:51pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/38 "2004-02-11T23:51:37Z")
And the results are: 220/240V kettles: 2’ 30" 110/120V kettles: 4’18" Stoves: 6’10" So US/Canuck kettles are certainly slower, but stoves are slower still. ---
**Author:** ![GorillaMan](https://avatars.discourse-cdn.com/v4/letter/g/50afbb/32.png) [@GorillaMan](https://boards.straightdope.com/u/GorillaMan)\ **Post date:** [February 11, 2004, 11:56pm UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/39 "2004-02-11T23:56:54Z")
Anyone for a celebratory 220/240v cup of tea? 😃 😃 ---
**Author:** ![TheLoadedDog](https://avatars.discourse-cdn.com/v4/letter/t/35a633/32.png) [@TheLoadedDog](https://boards.straightdope.com/u/TheLoadedDog)\ **Post date:** [February 12, 2004, 12:26am UTC](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040/40 "2004-02-12T00:26:43Z")
This is what I love about the SDMB (and the internet generally): **amarone** , sitting at home in Georgia, merely has to enter a few dozen keystrokes into a PC, and complete strangers all over the world, in several continents, dutifully trot off to their respective kitchens, carefully measure the prescribed amount of water into their heating vessel of choice, get the stopwatch ready… Very cool. [Previous page](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040.md?page=1) [Next page](https://boards.straightdope.com/t/are-110v-electric-kettles-too-slow/228040.md?page=3)