Small space heaters are typically used when the main heating system is inadequate or when central heating is too costly to install or operate. In some cases, small space heaters can be less expensive to use if you only want to heat one room or supplement inadequate heating in one room. They can also boost the temperature of rooms used by individuals who are sensitive to cold, especially elderly persons, without overheating your entire home.
Space heater capacities generally range between 10,000 Btu to 40,000 Btu per hour. Common fuels used for this purpose are: electricity, propane, natural gas, and kerosene (see the wood and pellet section for information on wood and pellet stoves).
Although most space heaters rely on convection (the circulation of air in a room) to heat a room, some rely on radiant heating; that is, they emit infrared radiation that directly heats up objects and people that are within their line of sight. Radiant heaters are a more efficient choice when you will be in a room for only a few hours, if you can remain within the line of sight of the heater. They can be more efficient when using a room for a short period because they avoid the energy needed to heat the entire room by instead directly heating the occupant of the room and the occupant’s immediate surroundings.
Safety is a top consideration when using space heaters. The U.S. Consumer Product Safety Commission estimates that more than 25,000 residential fires every year are associated