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Space Heater Efficiency

Graphic of someone using a space heater. Electric space heaters are a good way to provide extra heat for rooms that seem to stay cold or for someone is always chilly. 

Please remember they can be a large contributor to high winter electric bills and a leading cause of home fires. 



Cost Calculation 

All space heaters are rated in watts found on a tag located on the back of each unit. Most heaters are 1,500 watts.

Electric usage is billed in kilowatt-hours or kWh. A kWh is 1,000 watts used for one hour. Central Electric Cooperative (CEC) charges 10.9 cents per kWh.

A 1,500 watt space heater used for eight hours will cost:

  • 1,500 watts = 1.5 kWh X eight hours = 12 kWh 
  • 12 kWh X $0.109/kWh = $1.31/day
  • $1.31 per day X 30 days = $39.30 per month

That same heater left on all day (24 hours) would end up costing a whopping $117.20 in a month! Multiple heaters can really raise your electric bill significantly.

Beware of space heater efficiency hype that promises to reduce your heating bill by 50 percent or more. The only way to accomplish this feat is by turning down your central heating system back to between 50 to 60 degrees, and only use your space heater in the area you are occupying. 



Heater Types

  • Infrared heater: Radiates heat to the objects and people directly in front of it, rather than warming room air. These are great for people sitting in one place, such as a desk or work bench. Note that the heater surface can get very hot and should be used with care around children and pets.
  • Convection liquid heater: Unit is designed to heat a liquid (oil or water) without having hot, exposed heating elements. They take longer to bring a room area up to a desired temperature, but will keep a room temperature more uniform once the thermostat is satisfied. Remember that on mild days, the unit still gives of heat when turned off.
  • Fan electric heater: Provides quick heat to an area and is easily portable. The disadvantage is that rooms quickly become cool once fan shuts off.
  • Infrared combo heaters: The most recent electric heater interest is in the infrared combo heaters (names like Eden Pure and Amish heaters). They combine infrared technology to heat internal hollow copper tubing. A fan distributes heat off the tubing into a room to provide quick comfort with safety in mind. Fan speeds are variable to reduce unwanted noise. Comfort is a large selling point, but operational cost savings have not met advertised figures.



Sizing a Heater

A good rule of thumb is to supply 10 watts per square foot of desired heated space. A standard 1,500 watt unit can keep up to 150 square feet comfortable.


Safety in Mind

Always keep safety in mind with space heaters of any type. Avoid using extension cords unless they are rated to carry at least 12 amps. Keep units safely away from children,pets and furniture/curtains. And never leave a heater on unattended.





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