I was wondering why the Kill-A-Watt wattmeter that I normally leave things in the room plugged into was beeping. Turned out that having an electric kettle and a space heater both on on a circuit were enough to drive the power usage over the 1800W that a normal US household circuit can provide, and that apparently the thing beeps in that case. It let me flip off the kettle before the circuit breaker flipped, which was nice.
I think I might look into a low-wattage, vacuum-insulated (to help compensate for the fact that the heat will have to be put into the water over a longer period of time) kettle.
But I want to start a fire inside of my walls :(
A space heater is limited in its heat production to the amount of power that the circuit can deliver via electricity. Unless, of course, you use that electric power as a starter to release some of the stored chemical energy of the items in your home. At that point you can continue to produce light and heat even after shutting off the electrical power.