Keep in mind that this will NOT heat your whole home, not even close. However, you’d be surprised at how it will heat up a closed room and will keep you from getting hypothermia. Essentially it takes the heat from the candle that would normally go straight up and radiates it out once the terra cotta begins to retain the heat.
Repeat this step again with the small pot
Note: be careful not to tighten too hard and break the pot
It takes a few minutes before it feels warm to the touch because the inner pots heated before the outer pot will retain heat.
Keep in mind that the last thing you need in a blackout is a fire. Make sure all materials are on a non-flammable surface. One idea is to put all of the pieces inside a large cooking pot.
One candle will heat up pretty well. If you can get a glass jar candle that has two or three wicks even better!