For people who run an all-electric heat pump, running on emergency heat is more expensive; therefore, you shouldn’t run on emergency heat for an extended period of time, just until your heat pump is fixed. In comparison to the cost of heating with gas or oil, there is no clear answer as to whether emergency heat is more expensive or not, as you would have to factor in the efficiency of the system, the cost of fuel, and many other factors. However, an all-electric system will always cost more than any other system.