On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most efficient you can get from a demostic kettle.
There's also quite a differnce between hot water and bioling water.