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Are Costly, "Wooden Box" Electric Heaters Worth the Money?Nov 28 '10 (Updated Dec 04 '10) Write an essay on this topic.
Popular Products in Heaters
The Bottom Line Consumers should beware of claims that one electric heater is more efficient than another, or that a 1,500 watt heater can heat 1,000 square feet.
They're marketed in "info-mercials" and in full-page newspaper ads with images of cats perched on top of them and children playing next to them in presumed comfort and safety, and with claims of being more efficient than "conventional" electric heaters. Big savings in the form of lower heating bills can accrue to those who are willing to bite the bullet and pony up the $300 to $500 price of these "wooden box" heaters, the ads claim. (Some of the heaters aren't actually made of real wood, but are instead constructed of plastic designed to look like wood.) Here are some facts relating to the common claims made for these costly heaters: "Heats up to 1,000 square feet." Many companies selling these heaters make this claim, implying that a 1,000 or 1,500 watt electric heater could replace the heating system in an entire small house or apartment. Perhaps, if the temperature outside is no lower than about 55 degrees F, this might be the case, but the heat requirement of 1,000 square feet in the vast majority of the United States is far more than 5,000 BTU, which is the amount of heat generated by a 1,500-watt electric heater. (That's why homes have a 50,000 BTU -- or greater -- furnace, and not one of these wooden box "furnaces.") In truly cold weather, say, below 32 degrees F, the area heated by a 1,500-watt electric heater is about 150 square feet -- one 12' x 12' room, in other words -- so not a very large room, at that. Yes, you might save money with this (or any) electric heater if you're willing to turn your home heating system down to 50 F or so and stay in one room of your house, but no 120-volt, plug-in electric heater can heat a large area of a home unless it's not very cold out. "Uses infrared heating technology." The manufacturers like to use this "infrared" term because it sounds high-tech, like some sort of recent discovery, and they imply that this improves the efficiency of these heaters beyond that of heaters costing a tenth the price. It doesn't, and here's why: First, infrared radiation is a heat delivery method, not a form of heat, so the total amount of heat produced, and the overall effect on room temperature, is no different for infrared heating than for any other form of heat. Second, these heaters do not actually deliver infrared heating. While they do use bulbs and/or quartz elements that could deliver some share of their heating via infrared radiation, this is only a factor if you are exposed to that radiation by being within "line of sight" of the bulbs. This is not the case with the wooden box heaters because the elements are enclosed in the heater. In contrast, some heaters selling for modest prices do deliver actual infrared heating. Examples include quartz heaters with visible elements, farm-type heat lamps, incandescent light bulbs, and most other electric heaters with heating elements that get hot enough to glow. The potential energy saving from a true infrared heater is not that it yields more total heat than any other type of heater, but that the heat can be directed at the people who want to be warmed up, allowing them to feel more comfortable even before the air in the room gets warmer. If infrared radiation does not strike people, it simply strikes objects, which then transfer their heat to the air -- convection heating, in other words -- and that's what occurs in these wooden box heaters. The bottom line is that these $500 heaters warm your room via convection, the same as most $20 fan-forced heaters sold at hardware and discount stores. "Save Hundreds on Heating Bills." With these or any other portable electric heaters, it's possible that the user can save money by lowering the central heating thermostat and living not in the whole house but in one room. This is a situation that is probably not going to be satisfactory to very many people, and the savings may not even occur to begin with. Why? All electric heaters are 100 percent efficient, but that does not mean they're cheap to operate, because electricity costs more than most other forms of energy. This is especially the case in areas with high electric rates, such as New York, Massachusetts or California, where people pay 15 to 20 cents per kilowatt-hour. In these places, the wisdom of even using one electric heater in a single room is questionable. Some numbers to consider: Many people who buy a supplemental electric heater do so to avoid running a natural gas furnace. The average natural gas rate in the U.S. at the time of this writing is $1.40 per therm (100,000 BTU) of gas. The average U.S. electric rate is 12 cents per kilowatt-hour. Assuming the gas is burned in a furnace that is 80 percent efficient (the lowest efficiency furnace currently available), purchasing 100,000 BTU of heat with a natural gas furnace would cost $1.75. Purchasing the same 100,000 BTU of heat with an electric resistance heater at 12 cents per kilowatt-hour would cost double that -- $3.52. In the Northeast, where many people have costly-to-operate oil furnaces, the electric rates are also generally higher than the national average. At the current average price of $3.10 per gallon of heating oil, the cost of 100,000 BTU of heat is $2.75, considering an 80 percent efficient oil burner. But, at 15 cents per kilowatt-hour, the cost of electric heat goes up to $4.39 per 100,000 BTU, so it's still more than half again the price of oil. When a heater that's supposed to save you money is producing heat at double the price per BTU as the home heating system you already have, you're fighting an uphill battle to save money. Still, you could probably save a few bucks, even with this costly form of heat, by heating only one room (a couple hundred square feet, at most) rather than your whole house with any electric heater. But, in reality, most of the "energy savings" that occurs with these heaters is illusory -- not really savings at all, but simply the transfer of heating energy usage from one bill to another. The gas bill may go down $50, but the electric bill doesn't come the same day, and when it shows up and is $50 or $60 higher, some people fail to correlate those two things. Finally, the most ridiculous cost-saving claim made for these heaters is that they're useful in homes that already have electric heat. If a home has electric resistance heat, such as electric baseboard or wall-mount fan-forced heaters, the home is already being heated in exactly the same way as it will be with one of these costly heaters. If a home has an electric heat pump, the heat pump produces heat for half to one-third the price of an electric space heater. Using one of these heaters to avoid running a heat pump amounts to voluntarily giving your electric company a rate hike. "Safe for Children and Pets." The design of these heaters does appear to be consistent with safety, but so are the designs of many other heaters on the market, such as electric radiators. Also, claims of safety for any electric heater need to be tempered by the fact that many electric heater fires originate not with the heater itself, but with the wiring delivering power to the heater. Any electric heater puts a major load on a home's electric wiring, and there can be problems in the wall receptable, the wiring leading to it, or anywhere else in the home's wiring system. Clearly, a fire that originates outside the heater in the home's wiring is not the fault of a heater manufacturer, but consumers weighing the safety of any electric heater do need to consider this factor. In terms of safety in the home, electric radiators are also very safe because they have passive safety features such as an enclosed heating element and a moderate surface temperaure that's below the ignition point of household combustibles. Despite the word "radiator" in their name, electric radiators deliver most of their heat via convection, the same as the wooden box heaters. "Does Not Dry The Air." When the temperature of a given parcel of air is increased, its relative humidity goes down. For this reason, all heaters, no matter what type, will have a drying effect on the air. However, combustion heaters, such as gas furnaces, can dry the air in an additional way by creating an oxygen demand that draws outdoor air into the home. When cold outdoor air comes in at an outdoor humidity of perhaps 40 or 50 percent, and this cold air is raised to 70 degrees or so, its relative humidity becomes very low -- in some cases reaching "desert" levels of 10 to 15 percent. The "wooden box" heater manufacturers who claim their products do not dry the air may be alluding to the fact that, by heating the air in a home electrically rather than with a combustion furnace, the furnace will not have as much opportunity to dry the air. This is true, but the same can be said of every electric heater on the market. Also, many newer gas and oil furnaces use outdoor air for combustion, so they do not dry the air any more than electric heaters do. "Cleans the Air." A small filter attached to some of these heaters would remove some of the larger dust particles in the air. The quantity of air moved by a heater is not large, so the cleaning effect on the air, if any, would be minimal. A fan-forced HEPA air purifier would have an exponentially greater cleaning effect on the air for a far lower price. Summary People buy products for many reasons. Just as there's no harm in paying $100,000 for a car -- if you can afford it -- it's certainly okay to pay $500 for an electric heater. But, evaluate these heaters with the facts in mind: No 120-volt, portable electric heater of any type, whether it costs $20 or $500, can deliver enough heat to substitute for a home's furnace. All electric heaters, no matter the price, will deliver the same amount of heat per watt of energy consumed, so all you have to do is look at a heater's wattage rating to determine how much heat it will produce. Because electricity is costly as a heating fuel, it's difficult to save money by transferring your home's heating load from a less costly source, such as gas or oil, to electricity, which costs more. While wooden box heaters appear to be safely constructed, they are probably no safer than many other heater designs, such as electric radiators. All electric heaters, no matter how costly or what type, place large demands on a home's wiring, which can create safety concerns.  |
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