If you have a fairly cold house and run a space heater in a dedicated "snake room" you might notice a jump, not much though unless it is a very inefficient one. If you do use one get one of the newer oil filled radiators from Kenwood or Honeywell sold at HD or Lowes. I just use cages with built in belly heat and no space heater. The room stays at about 75. No real diff in the power bill with heat tape or UTHs (unless you have 150 cages)