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johnthesecure | 4 years ago

That's enough energy to boil those kettles dry, if my calculations are correct. To bring them to the boil, 59MJ would run about 600 kettles.

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advisedwang|4 years ago

Water has a specific heat capacity of 4184J/kg/C. Lets say to get to the boil you need to go from 20C to 100C and that a kettle holds 1.75L.

59MJ / (80C * 4184J/kg/C) = 176kg ~= 176L ~= 100 kettles.

Water has a latent heat of vaporization of 2260 kJ/kg. So to boil it dry:

59MJ / (80C * 4184J/kg/C + 2260 kJ/kg) = 22kg ~= 22L ~= 12 kettles.

I have no idea what the journalist calculated.

zucker42|4 years ago

I suppose it's possible that the "standard" kettle size is ~3L. They don't seem too uncommon on Amazon.

ketozhang|4 years ago

I think the journalist is calculating load capacity. A 1500A @120V kettle requires 0.18 MW. Rounding up, 60 kettles requires 12 MW. It's not how much water you can boil, it's how many kettles you can run at the same time.

moron4hire|4 years ago

Did you factor in the inefficiencies of the power distribution grid and the heating element of the kettle? I'd say the journalists are just repeating what they've been told by the scientists, and the scientists factored inefficiency in on a calculation similar to your first.

ComputerGuru|4 years ago

Maybe they meant from a frozen solid state?