Radiant electric heat is produced by running an electric current through one of several different types of device, with the goal of producing heat that radiates passively to warm a room or outdoor area. This type of electric heat can be produced by elements installed within a floor or by units mounted externally on walls or outdoor fixtures. Such heating fixtures warm a space quickly, without the use of the blowers that are common in some other heating designs.
The simplest form of radiant electric heat relies on an electrical current that runs through a resistor. As current passes through the resistor, electrical energy is consumed and radiated as heat. Electric baseboard heaters often employ this technology, as do many space heaters. The specific type of resistor used in these applications varies. Older heating systems tended to use metal wire, but newer models are more likely to employ ceramics, sometimes with additional diffusion systems, such as oil-based radiators, to ensure more even heating.
Heated floors are becoming an increasingly common feature in modern homes, and radiant electric heat is one option for heating them. In such systems, either formed assemblies of heating wires or individual heating cables are buried in the floor and then heated by electricity as needed. This type of system is less complicated to install than a fluid-based floor heating system and suffers from fewer potential maintenance headaches. Such systems can consume a substantial amount of energy, however, requiring roughly 12 watts per square foot of floor to operate.
Other varieties of radiant electric heat feature units that run a current through bulbs or filaments designed to produce infrared radiation that is emitted from wall-mounted units. These devices have the advantage of producing heat that can be felt immediately by anyone in range of the heating unit, meaning that a space heated in such a fashion feels warm very quickly. Such heating systems also have the advantage of not relying on blowers or combustion to heat or move air, and, therefore, are less likely to remove too much humidity from winter air or stir up household allergens and dust. This type of system can be ideal for heating rarely-used spaces, as it warms quickly and can be left off when the spaces are not in use.
This type of electric heat is one common choice for the heating of outdoor spaces, where it can be installed permanently. Alternatively, many varieties of portable and temporary electric heaters are available and can be deployed as needed to heat an outdoor table, deck, or patio.