Chris Green pretended :
How many people have houses where doing this is remotely practical?

Firstly you don't want to have virtually nothing in the house working
for an hour (heating, cooking, radio/TV, internet, whatever) and
secondly there are almost certainly things that you can't easily turn
off while leaving a circuit live for the 1kW fire.

Yes, it *could* be done but it's a sledgehammer to crack a nut.

Well, I have all of those things and much more, but switching them all
off for an hour would certainly not be an issue.

Your solution to the OP's problem is...?