The efficiency of space heaters

Space heaters are small, versatile and generally good at warming a room. Many people consider purchasing one at some time or another. However, some manufacturers claim that their electric space heater can cut a home’s heating bill significantly.  Before you make a purchase, you need to learn all you can to see if these claims hold up.

Some basic facts about space heaters can help you get to the truth of the matter.  Space heaters work best as a supplement to a furnace or heat pump – they are rarely used as the primary heating source. Three main types of space heaters are available: radiant heaters, convection heaters and combination heaters. These can usually be purchased for $30 to $100.



You might be better off taking a look at some easy and inexpensive energy-saving measures in your home. Adding caulk and weather stripping around doors and windows; adding insulation to attics and exposed walls; cleaning or replacing furnace filters; moving furniture or obstacles away from heat registers; insulating duct work and closing blinds or curtains or night could easily solve your heating problems without additional heating equipment.

Radiant Heaters

A radiant heater heats objects and people—not the air—in a room. Their best use is in rooms where those who want to be warmed are in the direct line of sight of the heater. Radiant heaters can be a good choice if you are in a room for a short period of time and want instant heat. They can pose a burn or fire risk, however, and should not be placed near furniture, drapery, pets, or small children.


Convection Heaters

Convection heaters are designed to heat the air—not people or objects—in a room. Hot air from the convection heater rises to the ceiling and forces cooler air to the floor. The cooler air is warmed by the heater and rises to the ceiling, creating a cycle that continues as long as the heater is on. These typically are either baseboard or oil- or water-filled heaters. The oil- or water-filled heaters are the most efficient types and often look like a small radiator. These units generally become warm to the touch and, compared to a radiant heater, have a decreased fire and burn risk.


Combination Heaters

As the name implies, combination heaters try to merge the best features of the radiant and convection heaters. They often have an internal fan that aids in distributing heat throughout the room. These heaters are versatile. But they typically do not do as well as radiant or convection heaters.

How and where will you use it?

Before purchasing a space heater, you should decide how and where it will be used, and whether a radiant, convection, or combination heater will do the job best. Combination units are versatile, but you will more likely get better performance from a radiant or convection heater. Use a radiant heater if you want heat instantly and will stay in one spot. If you need to warm an entire room, a convection heater should do the trick.

So can using a space heater cut your home heating bill? Maybe. Most space heaters use between 600 and 1,500 watts of electricity. A homeowner using a space heater 8 hours a day, 5 days a week, for a month, would spend about $15.26 for this additional electricity. However, space heaters can heat only a small space. You can save significantly if you use the space heater in this way: turn the thermostat of your central heating system down considerably (as low as 50 degrees in some cases). Place the space heater in a room occupied by people and close that room off from the rest of the home. This method of “zone heating” will save money.

 Space heaters do have their place in warming a house, but they simply cannot replace energy-efficient central heating or weatherization improvements to the home. For example, all-electric space heaters produce 1 unit of heat for every 1 unit of electricity consumed; in other words, they are 100% energy-efficient. Those that use natural gas are 80% efficient. In comparison, geothermal heat pumps can produce more than 3 units of heat for every unit of electricity consumed, making them 300% efficient.

As with any technology, before purchasing a space heater, you should understand how the device is used, as well as the energy claims of the manufacturer. While it may be technically possible to cut your heating bill by 50% using a space heater, it is impractical for most people.

Source:  Brian Sloboda, program manager specializing in energy-efficiency for the Cooperative Research Network (CRN), a service of the Arlington, VA.-based National Rural Electric Cooperative Association.  CRN monitors, evaluates and applies technologies that help electric cooperatives control costs, increase productivity and enhance service to members.

One response to “The efficiency of space heaters

  1. I would definitely agree that zone heating can be very impractical for most people. Something I would warn for those trying zone heating, do not turn off your thermostat altogether! Especially in freezing climates. This can result in broken water pipes and much more damage and costs.

Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s