I once annoyed a physics tutor by pointing out that kettles made a noise and were also 50Hz radio transmitters - albeit ridiculously ineffective onesPlus the thermal mass of the kettle which will be quite small you'd think (as opposed to my metal whistling kettle). Your figures did look right when I checked them (for what that's worth).
Theoretically, but you have to account for heat losses. Thermodynamics, innit?physics never really was my thing, but doesn't it take the same amount of energy to boil X amount of water from a starting temperature of Y degrees, irrespective of whether it's a low power kettle that does it slowly or a high power kettle that does it quick?
It will make you attractive to a very specific kind of womanI may use that as a new chatup line ..
"making coffee for two would save 26 KJ "
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A basic understanding of calorimetry is one of my non-negotiablesIt will make you attractive to a very specific kind of woman
I had this notion that the metal was insignificant - but I'm not ready to go for plastic yet ...There are bound to be losses - your kettle isn't particularly well insulated, so it's going to be radiating some of that heat while it's boiling, and any steam that emerges during the process of boiling will represent a net loss of energy to the water in the kettle. So 1680 sounds quite reasonable...
ETA: ah, you'd already got there. Ho hum
No need to worry as it's ~5 times cheaper than electric.
You could do an experiment with a measured quantity of water, a microwave, and a thermometer. I suggest not actually going for a full boil, though, as that is likely to be dangerous, and you're not dessiato.
Our kettle, Dualit naturally, uses .13KW to boil the water necessary for my tea (a GOOD two cups) and Mrs Voltzs coffee (a LARGE mug) - this reads as just over 4 cups on the scale on the side of the kettle
this is true, not huge over a minute or two though I was assuming.
Magnetrons are apparently 70 percent efficient - but the key thing is we tend to use plastic and glass vessels ...You could do an experiment with a measured quantity of water, a microwave, and a thermometer. I suggest not actually going for a full boil, though, as that is likely to be dangerous, and you're not dessiato.
My guess is that microwaves are probably less efficient at turning electricity into radiation and thence heat than even the humble kettle.
You sure? 800 W * 2 minutes for induction =0.03 kWh for 1/2 pint cup including fairly massy steel kettle.
that's the reading that the plug in meter gave. and I've repeated the test a few timesYou sure? 800 W * 2 minutes for induction =0.03 kWh for 1/2 pint cup including fairly massy steel kettle.
Glad to see we're getting down the essentials of Energy Saving for Britain
It's bigger than the old camping fridge but still fits the space and I switch on in an hour. I've lost remarkably little that's perishable over the last three weeks even in the warm weather by transferring stuff from freezer to a cool box.
Best guess, I'm boiling four times as much as you, which sounds about right
IME, it's all about the power supplies - microwaves have big old transformers in them, which are never 100% efficient, and rectification isn't 100% efficient, either, so I do wonder what the overall plug-to-cavity efficiency works out as, even before we start thinking about vessels, etc...
Oh that one really boils my piss (SWIDT?Aha of course, and what with me boiling only an environmentally responsible amount of water for drinks.
) - my ex used to stick a good litre and a half into the kettle for one or two cups of tea, and NOTHING I could say would persuade her not to.
Oh that one really boils my piss (SWIDT?
After a while, you learn to judge it by weight...
I'm not too bad now but it's just too easy to hold the kettle under the tap, which is where the kettle cosy is useful. I must start measuring a cupful though.
