portable electic heaters - separating fact from fiction

Portable Electric Heaters

Separating Facts from Fiction

Portable Electric Heaters

• Basic Cautions– Requires adequate wiring– One portable heater can use most of the

capacity of a 15 amp circuit– Not intended for use with extension cords– Keep flammable items away from heaters– Some heaters have high temperature

surfaces when in use– Not intended to replace a properly designed

heating system

High Temperature Radiant

Low(er) Temperature Radiantand natural convection

Convective (Fan) Heaters

Convective Variations

Simulated Fire Ceramic

“Miracle” heater

No Miracle… heats the same as all convective electric heaters

“Infrared” comfort heater

• This is only an infrared heater if you crawl into the box… otherwise it is a convective heater!

• Same efficiency as all other electric resistance heaters

Cost of Electric Heating

• Operating a 1500 watt electric heater for one hour at an electric rate of $0.10 per kiloWatt-hour costs $0.15

• Using propane at $2.50 per gallon to make the same heat with a 90% efficient furnace costs $0.155

• How can you have 20% savings if the cost of operation is almost identical??

Savings Claims Explained

• The claims of 20% savings are based on the idea that you will turn down the temperature in the rest of the home and use the portable heater to keep the room you are using warm.

• If you leave your home thermostat setting the same AND operate a portable heater… your energy costs could be higher!

How Much Area Can They Heat?

• Rules of thumb will always get you in trouble - but…

• Generally the design heat load for a home ranges from 12 to 8 watts per square foot

• If we take the middle of the range, a 1500 watt heater could be expected to heat 150 square feet of area

Can Electric Heat Be Economical?

• Yes – An air source heat pump can take heat out of the air all the way down to 0ºF.

• Operates for half the cost of resistance heat on an annual basis

Air Source Heat Pump

• An air source heat pump works as an air conditioner in summer months and as a heater in winter months

• Worth checking into the next time you need a new central air conditioner

Ultimate Efficiency

• A ground source heat pump uses heat from the earth to heat the home in winter and cool it in summer

• Operates with just ¼ of the energy needed by resistance heating

• Highest first cost but lowest operating cost