Just having a little debate in the house as our kettle has died. Choosing a new one - but is a white kettle more energy efficient than a black kettle?

My argument: there's so much energy pumped into the water by the element in such a short space of time that any heat losses / gains due to colour are going to be miniscule. i.e. go for any colour you want.

But (suggests offspring) our kettle typically sits in bright sunlight in the morning in front of the kitchen window (when it gets used more).

so if it's black, the potential is to absorb *slightly* more energy than it emits...

And now I can't remember whether a black surface radiates more light than a white surface (without Googling, I believe it does, hence spaceship coatings are black where heat needs to be emitted faster)

...and then I started wondering if the kettle material makes an appreciable difference (e.g. plastic versus metal).

(I appreciate this thread is starting to get tedious if you don't have slightly geeky tendencies like me).