OV9

Simon wrote: Mon Feb 02, 2026 10:03 pm

Beany wrote: Mon Feb 02, 2026 7:23 pm It's not really, truly nerdy till you've looked at your leccy bill and seen how much it costs you to boil a usable amount though.

Time is money, and money is time!

No, the amount of power used to raise 1ml of water by 1 degree is a constant. If you can do it quicker then your electric bill won't go up, because you're using more power for less time.

Ah, but there is an efficiency loss from the induction setup, as it loses some power due to having to convert the 240v/50hz into multi-khz induction frequencies, that then has to traverse the gap to the kettle, the kettle will radiate some heat downwards due to having a ferric metal bottom, etc.

The regular kettle just pumps 240v/50hz straight into its element with no conversion losses.

You're not thinking needlessly pedantic enough.

(to answer my own question, I asked inAccurate Intelligence, and it thinks that induction 'wall to cookware' is reckoned to be about 85-90% efficient, a boggo leccy kettle is about 90-95% efficient, so an induction hob is going to use slightly more power to do the same Work (tm), probably costing a whopping £20 over your entire lifetime if you're having a few cuppas a day - but that's the horrible, tragic tradeoff you have to make for having a mug of water boiling in under 30 seconds. And that's actually quite interesting)

Also, an energy calcuation needs to account for any latent heat of vaporisation that might occur in isolated areas before the entire body of water exceeds the boiling point and is deemed to be boiling as a whole.