What you should know about electric space heaters
They can add warmth in some spaces, but they can’t be a primary heat source for a houseBy James Dulley
Small electric space heaters in rooms can reduce your heating costs, but only if you set your central heating system (heat pump or furnace) thermostat lower while using them.
A common situation is when a room does not stay warm enough. A person gets chilly in that room and turns the central thermostat higher. This warms the entire house and more heat is lost through the walls, windows and ceiling. It is more efficient to use a small space heater in these kinds of rooms while maintaining the same or lower temperature at the central heat's thermostat.
The maximum heat most small space heaters can safely produce is about 5,100 Btuh (Btu per hour). That translates into about 17 cents per hour of use. Although this seems inexpensive to operate, a heater operating just eight hours per day over a month's time will add $40 to the home's electric bill. Double that if you use two heaters. Houses typically use central heating systems with a capacity of 50,000 to 100,000 Btuh, so a single space heater cannot heat an entire house. Be wary of ads stating a small electric space heater can allow your central system to run dramatically less for major savings.
There's not a "best" electric space heater for every situation. It depends on the room and how you plan to use the heater. For example, are you looking for quiet heat in a bedroom at night, heat for just one person watching TV, or will there be a group of people in a large room?
You can choose between direct radiant and convection (air circulation) space heaters. Both types have their advantages. If you have young children, there are also safety considerations.
Radiant space heaters
Radiant style heaters heat quickly. These use a red-hot ribbon, long quartz or carbon tubes to produce infrared heat radiation similar to the sun's rays. They primarily heat objects and people directly in front of them. Carbon tubes produce infrared heat which penetrates objects and skin slightly below the surface. This makes it very comfortable, effective heat.
Radiant heaters are quiet and ideal for heating a specific spot. For example, I use one to keep me warm while I am writing. To heat a slightly larger area, select a model which automatically oscillates.
These heaters can be hazardous if not used carefully. They should not be placed near anything flammable such as curtains, bedspreads, flammable liquids. In fact they should not be left running when no one is in the room, especially if young children are around. It's not a good idea to use an extension cord with these, either.
Convection space heaters
Convection heaters are designed to heat the air in the room. This is often done using a built-in fan to circulate room air over the heating elements. Oil-filled, old radiator-style heaters use natural air circulation (as hot air rises) to move room air over the heat source, gently warming a room without bursts of heat.
A convection style heater can heat an entire, large room effectively. There are models with a thermostat and multispeed fan to control the heat output. Also, a ceramic convection heater is safe around young children. If the air flow gets blocked, the heating output automatically drops, and there are no red hot ribbons.
For a bedroom, where quiet operation is important, you can use an oil-filled radiator or a convection heater with a low-speed setting. Another option is a radiant model if you don't mind the red glow. A horizontal shaped one will heat the entire bed area.