General guidelines- you are allowed 1000 watts per bedroom. 2 bedroom house, 2000 watt setup; 3 bedroom, 3000 watt setup. If you are under that, then you shouldn't have anything to worry about (unless you are stealing electricity, but if you are worried about power consumption, I doubt that is an issue.) Only 2 things to worry about after that: the smell, and not telling ANYONE about it. It is hard to not tell people about your setup, but that is what this forum is for.