An oil heater (oil-filled radiator) uses electricity to heat thermal oil inside its fins. The heated oil radiates warmth evenly, keeping rooms warm for hours - even after the heater is switched off.

Yes. Oil heaters are more energy efficient than fan heaters because they retain heat for longer and don't need to run continuously. Many models also include adjustable thermostats and eco modes to reduce electricity use.

Oil heaters use electricity, but they are highly efficient. Once heated, the thermal oil retains warmth, meaning the heater cycles on and off less frequently, which helps keep running costs lower.

No. The oil inside is permanently sealed and never needs replacing. They are odourless, clean, and safe to use indoors.

Yes, provided the heater has built-in safety features (most modern oil heaters do). They are designed for safe, continuous heating, making them one of the safest electric heaters for overnight use.