In our house we used to boil the kettle almost constantly, we are a large family, so there was a constant tea and coffee on the go. I bought a really inexpensive pump action flask, now I fill the kettle once in the morning, let it boil and then pour it into the urn. The water stays really hot till mid afternoon. And is also so convenient, no unscrewing of flask lids and you have instant hot water instead of standing around waiting for the kettle to boil.