An oil-filled radiator can heat up a room more quickly than a halogen heater can, although a halogen heater is more energy efficient than a radiator, so determining which is better depends on what the user is looking for. Oil-filled units are considered convection heaters, as they heat the oil itself, and then the heat from the oil raises the temperature of the air around it, while halogen heaters use radiant heat, which often works just as well in situations where people are not moving around, like heating a bedroom overnight. Reviewing the specific use of the heater is important before making a purchase.
A radiant heater works especially well for elevating the temperature in a small room or in a portion of a larger room. A halogen heater simply uses a halogen bulb to generate heat, as the light reflects off nearby objects and then sends energy in a specific direction. The sensation is similar to stepping out of a shaded area and feeling the sunshine. For someone sleeping in a dorm room or in a corner of a larger room, this is an economical way to provide heat overnight.
Oil-filled radiators heat the oil and send the warm air around the oil out into the room using a fan. The cost of the heater is cheaper than the halogen machine, but purchasing more oil over time brings the costs closer to even. For those heating an entire room, this is the better choice.