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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]

#71
post #51
post #47

Earlier quoted context omitted.

> Obviously the battery should be replaceable. (It should be in most electronics, really...) This is super wasteful when we can just hook up a heating element to an insulated tank and keep it hot like Quooker [0] does. Assuming the 3L tank, that would mean probably 20 minutes to heat the tank if it's entirely emptied for the US, but that's how long it would take to boil that water with an electric kettle _anyway_. If…

It doesn't have to be insulated like an insulated water bottle or anything, plastic is good enough for this. I have a cheap 120V kettle, nothing special, probably mostly plastic but with some superficial bits of stainless steel. After bringing a cup of water to a boil you can safely touch the base and anywhere on the kettle itself; there's not even an obvious sign of warmth anywhere except for the lid. If you don't b…

> It doesn't have to be insulated like an insulated water bottle or anything, plastic is good enough for this.

Yeah I agree, but I was responding to the point of: > The standard kettle already tries as hard as possible to insulate the heat

Which isn't true at all. They make a token effort.

> Also: a hot water tank is just another type of battery.

You're technically correct, the worst kind of correct.

> don't see anything terribly wasteful about the concept of putting batteries in a few more things. They're very recyclable, and already extremely abundant. It's not necessary, but neither is pushing several kW through a kettle just to get water to boil a bit faster. So really, that might be worth interrogating first...

It takes ~320 kJ of energy to bring a litre of water from room temp to boiling, no matter what way you spin it. The difference between pushing 1500w or 3kW into the hot plate is "how quickly do you get to boiling", and has basically no bearing on the total amount of energy used to boil the water. Running a 1500w kettle for twice as long will use the same amount of energy, from the same source.

Using consumable li-ion/alkaline batteries to supplement that energy is _terribly_ wasteful - we've been through the "reduce reuse recycle" loop already with waste, lets not do the same thing with rare earth metals to avoid running a single cable to household appliances.

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

#72
post #64
post #63

Earlier quoted context omitted.

I think you're thinking about it on the kettle side, and I was thinking on the breaker side. I think the kettle side would not care. It may be a ground fault in UK wires, but the kettle has no reason to detect it, and nothing sensitive enough inside to care. If I'm wrong, I'd expect to know shortly after starting the very first use. :)

You guys know he talks about this 4 minutes into the video, right? See also: https://diy.stackexchange.com/a/315031

One thing in that thread;

> Most UK kettles are not 3000W, and most of the ones that are, are junk. Y

They may not be 3 kW, but even the most basic of them are 2200W [0], and 3000W ones are readily available are not much more expensive [1]. They're also not really junk - they're a lump of plastic, a hot plate and a thermistor - the difference between a £8 one and a £80 one is almost all aesthetics.

[0] https://www.argos.co.uk/product/3102039

[1] https://www.johnlewis.com/john-lewis-kettle-1-5l/white/p5523...

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

#73
post #71
post #51

Earlier quoted context omitted.

It doesn't have to be insulated like an insulated water bottle or anything, plastic is good enough for this. I have a cheap 120V kettle, nothing special, probably mostly plastic but with some superficial bits of stainless steel. After bringing a cup of water to a boil you can safely touch the base and anywhere on the kettle itself; there's not even an obvious sign of warmth anywhere except for the lid. If you don't b…

> It doesn't have to be insulated like an insulated water bottle or anything, plastic is good enough for this. Yeah I agree, but I was responding to the point of: > The standard kettle already tries as hard as possible to insulate the heat Which isn't true at all. They make a token effort. > Also: a hot water tank is just another type of battery. You're technically correct, the worst kind of correct. > don't see anyt…

> Which isn't true at all. They make a token effort.

Look, the point was whether or not it would be okay to put batteries on it, not whether it would keep a drink warm for 12 hours. If the base is cool to the touch, I think it will be completely fine for batteries to be near it. If anything, making sure they're safe from shorting is probably a bigger concern.

> You're technically correct, the worst kind of correct.

The point wasn't to be technically correct, it's to point out that you can compare the properties of the two types of batteries like-for-like and realize that for many people interested in a faster kettle the boiling water tank idea might not be great. In America most homes have a water heater and it has to contend with the same sort of problem, only we use hot water multiple times a day every day (and at least in the Midwest, use LNG for heating it a lot of the time, which makes it economical if not particularly environmentally friendly.)

> It takes ~320 kJ of energy to bring a litre of water from room temp to boiling, no matter what way you spin it. The difference between pushing 1500w or 3kW into the hot plate is "how quickly do you get to boiling", and has basically no bearing on the total amount of energy used to boil the water. Running a 1500w kettle for twice as long will use the same amount of energy, from the same source.

Well duh. My very first post in this thread is estimating how much energy is required for a typical kettle to bring a U.S. cup of water to a boil. (Though obviously in reality you have to account for losses.)

My point here is that (a relatively small niche of) people are already doing crazy things like rewiring their houses (in America) to push pretty absurd power into kettles just boil water slightly faster, a time save that literally only even matters if you sit there and wait idly while the water heats up. The problem I have isn't that higher wattage kettles are somehow bad, it's that all of this time, effort and money for a time save measured in minutes is crazy. And it's the same for strapping batteries to a kettle or for keeping a water tank of boiling water too. I wouldn't bother with any of them, and don't. (But, as I opened this thread with, seeing how crazy people get over this, I do remain surprised at the relatively few battery kettles on the market.)

> Using consumable li-ion/alkaline batteries to supplement that energy is _terribly_ wasteful - we've been through the "reduce reuse recycle" loop already with waste, lets not do the same thing with rare earth metals to avoid running a single cable to household appliances.

I just counted and the room I'm currently standing in has 8 separate high capacity lithium ion batteries. We put batteries in our power tools, laptops, vacuum cleaners, tooth brushes, game controllers, wireless computer peripherals, air compressors, UPS units, the phone someone is currently reading this comment on, air dusters, garden lighting and certainly much more. Almost everything with electronics in it has batteries for something (if you inlcude smaller ones like clock batteries), and more often than ever, high capacity ones no less.

A battery operated kettle will forever be an expensive niche product, and it wouldn't even use that much battery in the first place. The environmental impact of all of those batteries would struggle to get to the level of 100 electric vehicles, and yet we are selling over 10 million of those per year.

Of all of the contrived and silly arguments, this is by far the most contrived and silliest of all of them.

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

#74
post #39

Earlier quoted context omitted.

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.

I've seen those around, even with an integrated carbonator to get sparkling water right from the tap. They're neat but also ridiculously expensive

https://www.quooker.co.uk/ - these are the only "boiling water" ones (as in 100 degrees C), but if you're ok with 98C, then you can get https://www.screwfix.com/p/swirl-danube-3-in-1-instant-boili... instead for 25% of the price.

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

#75
post #24

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…

I highly doubt that. Electric kettles are just about 100% efficient, and the only difference between a 3kW kettle and a 2kW one is how long it'll take to boil. The total energy consumed will be more-or-less the same. Are you perhaps conflating it with the EU regulations on vacuum cleaners going in around 2017? As with all EU regulations, this of course resulted in a decent bunch of EU-bashing in UK media by the usual…

Boiling at lower power uses _more_ energy to reach the same temperature. This makes a 2kW kettle on eco grounds especially dumb, yes, but that doesn't preclude people pushing for it.
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