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My car charger can boil water really fast [video]

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Re: My car charger can boil water really fast [video]

#31

Post by crote »

throw0101c wrote: post #9

He mentions induction 'hot plates' towards the end, and says that they're limited to the same 1800W and 120V as kettles, but there are "commercial" portable induction stoves that are 220V and can go up to 3500 and 5000W; e.g.: * https://www.vevor.ca/induction-cooktop-c_10592/vevor-portabl... * https://www.trueinduction.com/Commercial-Single-Induction-Co... Just need a NEMA 6 plug (GFCI/AFCI per code as well probably)…

Sure, but over in 230V-land 3500W hot plates are completely standard, and can plug into any regular wall socket. Same with microwaves and hot-air ovens: just put it anywhere on your kitchen countertop and plug it into the nearest socket.

We do also have a "kitchen plug" for high-powered appliances. Those go up to 7.3kW in their regular dual-single-phase 16A version, 11kW when wired with three phases (quite common in households these days), or even 17kW with the (understandably) rarely-used 25A plug variant with three-phase wiring.

And that's not even commercial equipment, just what you'd pick up at your local Best Buy equivalent. The commercial stuff uses CeeForm, which is a three-phase 16A/32A/63A/125A plug. Or it's getting hard-wired.

Re: My car charger can boil water really fast [video]

#32

Post by quickthrowman »

silexia wrote: post #2

I am a farmer with giant water pumps and center pivots that run on 3 phase 480 volt power. One of my pumps has 85 horsepower. I wonder if I could wire up some sort of custom made tea kettle and get water to boil in five seconds?

You could run (10) of these 9kW 480V three-phase immersion heaters [0] in place of your 85 HP motor, assuming ~110A FLA @ 480V = 91.5kW. The 9kW immersion heaters are 10.8A each at 480V three-phase (would be 75A if it was 120V single-phase!)

Just make sure you have somewhere for the steam to go, it takes up a bit more room than water ;)

Is your three-phase a corner-grounded delta service? I’ve never seen one in the wild but I hear they’re used for three-phase ag service drops that are strictly used to run motors. A and C are tapped normally on the secondary but the B phase is bonded to ground and also a line conductor, conductor color is white for B phase instead of orange.

[0] https://iseinc.com/_shop/480v-3ph-9kw-immersion-heater-47-14...

Re: My car charger can boil water really fast [video]

#33

Post by CarVac »

lxgr wrote: post #16

Great video, but coincidentally two weeks too late for me: I never knew about the boil auto-shut-off mechanism and the overheat/"boil-dry" protection circuit being two different things in some kettles. In those, pouring out the entire water before the auto-off had a chance to kick in can cause a situation where the kettle stays on (due to not enough steam being present to trip it), but the boil-dry protection circuit…

I have a kettle with 5°-settable temperature targets that has transformed my tea drinking.

It also has a function to hold temperature for up to 30 minutes, and because it has actual logic going on inside, when you lift it off the base it knows this and won't turn back on when you put it back.

Re: My car charger can boil water really fast [video]

#34

Post by quickthrowman »

JonChesterfield wrote: post #18

I'm sure there was a period where one couldn't find a 3kW kettle in the UK on power efficiency grounds, one was supposed to run a 2kW one instead to save the planet. But now when I search I find 3kW models again. So either that was a nightmare of some sort or sanity has prevailed. Chatgpt thinks this was threatened in 2010 then postponed in 2016 then cancelled, which vaguely aligns with my timeline of interest in tea…

A larger heating element is very slightly more efficient due to less heat escaping as the liquid is heated more quickly. Resistive electric heating is always 100% efficient no matter the size of the heating element.

Keep in mind that heat is constantly being transferred between things that are different temperatures, the faster something reaches the set point temperature, the less time there is to lose heat.

https://en.wikipedia.org/wiki/Heat_equation

Re: My car charger can boil water really fast [video]

#35

Post by holdit »

jnsaff2 wrote: post #23
JonChesterfield wrote: post #18

I'm sure there was a period where one couldn't find a 3kW kettle in the UK on power efficiency grounds, one was supposed to run a 2kW one instead to save the planet. But now when I search I find 3kW models again. So either that was a nightmare of some sort or sanity has prevailed. Chatgpt thinks this was threatened in 2010 then postponed in 2016 then cancelled, which vaguely aligns with my timeline of interest in tea…

UK power grid has the Eastenders effect. Where the ending credits of the Eastenders soap signals a large increase in power draw from the grid as people will put on the tea kettle at the end of the show. The grid operators have to dispatch enough power to cover for this. While the amount of energy used to boil water at 2kW is not significantly different from 3kW (2kW has a tiny amount of more atmospheric losses I thin…

Here's a video showing an engineer at the national grid bringing hydro-electric plants online at the closing credits of a popular soap opera in anticipation of the millions of kettle that are about to be switched on!

https://www.youtube.com/watch?v=slDAvewWfrA

Re: My car charger can boil water really fast [video]

#36

Post by malfist »

Nextgrid wrote: post #13
namibj wrote: post #4

Earlier quoted context omitted.

3-phase electeode Boiler comes to mind. Just have it as a pass-through with a grounded shield at the end to keep you from accidentally touching dangerous voltage.

Wouldn't that cause electrolysis and make the water unsafe to drink?

What do you imagine happens to water when it undergoes electrolysis?

Re: My car charger can boil water really fast [video]

#37

Post by Nextgrid »

malfist wrote: post #36
Nextgrid wrote: post #13

Earlier quoted context omitted.

Wouldn't that cause electrolysis and make the water unsafe to drink?

What do you imagine happens to water when it undergoes electrolysis?

It breaks down into its individual components which escape as gases. That alone shouldn't make the remaining water toxic, assuming a perfect reaction. But I guess the reaction isn't perfect due to things like impurities, the metals used as electrodes and so on?

Re: My car charger can boil water really fast [video]

#38

Post by fsh »

JonChesterfield wrote: post #18

I'm sure there was a period where one couldn't find a 3kW kettle in the UK on power efficiency grounds, one was supposed to run a 2kW one instead to save the planet. But now when I search I find 3kW models again. So either that was a nightmare of some sort or sanity has prevailed. Chatgpt thinks this was threatened in 2010 then postponed in 2016 then cancelled, which vaguely aligns with my timeline of interest in tea…

There was no such thing in the UK. ChatGPT is trained to produce text that fulfills the user's expectations. If you put a prejudiced prompt in, expect a corresponding result.

Re: My car charger can boil water really fast [video]

#39

Post by maccard »

jchw wrote: post #11
maccard wrote: post #10

Earlier quoted context omitted.

In the US. In the UK 2200W induction plates are readily available with a standard plug for ~£40, or if you spend a little more you can go to 3kW - [0] which is about the limit of most domestic circuits but is hotter than most gas hobs. If you _really_ want more than that you can go a little mental and use one with an integrated battery which can push out 10 kW [1] [0] https://www.nisbets.co.uk/nisbets-essentials-sing…

This begs the question, and I've genuinely thought this before, of why we don't just strap a battery to a kettle and end this silly debate. If it takes 5 minutes to boil a cup of water in a 1000 watt kettle, that's somewhere around 80Wh... I guess it would be kind of expensive, but couldn't you make a pretty fast kettle with some number of high discharge battery cells? (Well honestly, I guess the real answer is outsi…

That seems a terrible waste of batteries to me. A boiling water tap seems like a better idea to me - electric heater with a pressurised insulated vessel that just dispenses from your tap.

Re: My car charger can boil water really fast [video]

#40

Post by Mistletoe »

throw0101c wrote: post #9

He mentions induction 'hot plates' towards the end, and says that they're limited to the same 1800W and 120V as kettles, but there are "commercial" portable induction stoves that are 220V and can go up to 3500 and 5000W; e.g.: * https://www.vevor.ca/induction-cooktop-c_10592/vevor-portabl... * https://www.trueinduction.com/Commercial-Single-Induction-Co... Just need a NEMA 6 plug (GFCI/AFCI per code as well probably)…

I swear Vevor makes everything.
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