There are two types of heaters that might fall under "portable oil heater".
- First is an oil-filled electric heater and the other is an
- unvented oil-fired space heater, commonly referred to as kerosene heater.
Unvented fossil fuel heaters produce a litany of pollutants that are considered unsafe in a variety of jurisdictions Since the unvented kerosene heaters are unlikely to be a safe option for an occupied dwelling I will discuss the oil-filled electric heater.
The energy source in an oil-filled radiator is electricity. The wisdom of using an electric heater depends on the per kilowatt cost in your region.
- If your heater has a 1000 watt rating and your cost of electricity is $0.15/Kwh your cost to operate for one hour would be $0.15.
- If the element is activated 10 hours out of every 24 hours your cost per day would be $1.50.
Since your primary heat source is an air source heat pump electric costs are a major concern.
Oil filled radiators allow the heating element to heat up the oil which in turn holds heat and dispenses it into the room. The electric heater cycles on and off depending on the temperature of the oil and the temperature difference between the thermostat setting and the ambient air. The oil acts as a thermal storage mass and reduces the operating time of the electric heating element.
If you keep temperatures lower in most of the dwelling but use an oil-filled heater to elevate temperature in an occupied room you will reduce your overall energy bill. You sacrifice comfort in rooms that are unoccupied in exchange for individual room comfort and reduced energy costs. Depending on your lifestyle this might be a nice trade off.