You're thinking of resistive electric heat, a baseboard-style system. But in many areas an electric heat pump is common. This is a forced-air system, and contr

You're thinking of resistive electric heat, a baseboard-style system. But in many areas an electric heat pump is common. This is a forced-air system, and controlled by zoned thermostats just like traditional gas or oil heat. That said, such heat pumps actually have multiple states: * Cooling * Off * Heating * Emergency heat (aka Aux heat) That last one happens when the ambient temperature is so low that the heat pump can't scavenge enough heat, and needs to augment with resistive heat (which happens through the same forced air delivery). Thus, in extreme cold you may be using even more electricity than you normally would. I live near Austin. The only time I've seen the Aux Heat in use was during last year's February freeze, which at 6F was the lowest temperature ever recorded here. Even at the occasional 13F-15F temperatures, the heat pump still operates normally (albeit it at very long cycles).