Most small electric room heaters belong to one of two types: radiant or convective.
Electric radiant heating comprises several types of small portable heaters and also electric radiant panels, attached to ceilings and walls. These heaters provide quick spot heating and are designed to heat people in their direct line of sight.
Electric convective heaters (electric baseboard, oil-filled heaters….) are different: they are designed to heat the air; not objects or people. They heat by circulating hot air.
In practice things are not so clear-cut. Many new small space heaters provide both radiant and convective heating; but they mostly belong to one of the two types, and the distinction between electric radiant heating and convective heating is very important when choosing.
Radiant space heaters
Radiant heaters emit heat in a specific direction. They may use a variety of heating elements: panels, ceramic plates, carbon tubes, metal coils, halogen lamps...
Radiant heaters are especially designed to heat people, not entire rooms. They are best for spot heating, because they deliver focused warmth to people and the areas directly in front of them. A radiant heater provides nearly instant warmth to a specific area.
Over time they may also increase the room’s air temperature, but their ultimate goal is to heat people directly.
Advantages of electric radiant heaters
Radiant heating has obvious advantages, namely a quick heating and small energy consumption.
Radiant heaters can heat almost instantaneously the people in their line of sight, and should be turned off when residents leave the room.
Turning them off is very important for their effectiveness.
Bottom line: the low price and easy installation and maintenance of radiant heaters can make them an advantageous choice in some electric heating strategies.
advantages and disadvantages of Convective space heaters
These heaters has some obvious advantages and disadvantages: they are quieter than radiant-fan heaters, and provide steady temperatures and a comfortable and healthier type of heating.
But on the other hand they take longer to heat up (a hour or so, to heat a room), and they end up consuming larger amounts of energy - something that can make them unsuitable for heating large spaces, or for rooms and homes with low levels of insulation.