Sunday, October 19, 2008

How to boil water


A friend told me he'd been fighting with his kitchen-cohabitants over the question of whether to simply use the gas to make hot water for pasta, or whether to use the kettle, then put it in the pot.
To answer this question quantitatively, I did some experiments and I've written a new webpage, How much is inside HOT WATER? The page assumes that the motivation is to save energy. The conclusions apply to Britain today and to similar countries.

My conclusion is that using the gas hob is slightly better in energy terms than using the kettle; but my recommended behaviour depends on the time of year. In the winter, if you would like to have more heat in your kitchen, then using the gas hob alone is definitely best; in the heat of summer, using the kettle may be preferable.

Disclaimers, small print...
If your motivation is to save money then the answer will depend on your fuel prices. If your motivation is to cook the pasta as fast as possible then you should use neither method alone - you should use both the kettle and the hob, with roughly half in each.