Making the rounds on Facebook, along with stories about marines one-upping their atheist college professors and inspirational quotes set against stock photos of a sunset, has been the claim that you can heat your home for pennies a day using a few candles and a terracotta pot.
The claim has some truthiness about it. You burn some candles in a pot, the pot retains the heat and then slowly releases it, heating your house. Apparently other people think this is plausible as well, because companies, such as Egloo, have started producing terracotta units for that purpose.
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A few things give me pause, however. The first is a personal bias I have regarding the people who share such claims: they’re the same well-meaning, but misguided people who post articles from sites with names like gaiamotherearthawesomenaturenewz.tumblr.com that claim WiFi signals will kill you or that a nurse was disappeared for questioning the efficacy of child vaccinations. The second is my skepticism regarding the sudden explosion of these heaters in the Internet’s consciousness; if these worked as advertised, why have they just been discovered now? why haven’t we been hearing about them for generations? Another question: why is this more powerful than simply burning a few candles openly?
Then there’s this, from Egloo’s indiegogo page:
The air intake of the external dome facilitate the outgoing of the warm air stored between the covers, allowing thermal exchange with the room environment.
After only 30 minutes the temperature of the environment surrounding the Egloo will be increased between 2° and 3° degrees.
…
Terracotta is a material particularly suitable for Egloo because the heat, rapidly stored, is slowly and gradually conveyed to the environment by thermal radiation.
That description, aside from the negligible heat increase of two-to-three degrees, is extremely vague. Space heaters, the godless electric kind you can buy at Home Depot, advertise their power and how many square feet of space they will heat. As for specifications, Egloo claims to “slowly and gradually” heat “the environment surrounding it.” I realize exact specifications fly in the face of the DIY, off-the-grid mentality of the design, but for the $50 price of the Egloo you can buy something that’s been tested and proven to work in areas of at least 300 square feet.
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This claim feels like an urban legend. That’s not to say it is. Unfortunately Snopes, my go-to site for such things, has nothing on the topic. I’ve found a few blog posts and YouTube videos in which people do their own experiments (some claiming to have debunked the design, others that it’s the miracle it purports to be) but nothing from a publication such as Consumer Reports or from someone with some credentials following his or her name.
Some input from those people would be spectacular. I lack the ability to answer these questions on my own because math and science are my personal hell. I’m also reluctant to give one anonymous YouTube voice any more credit than another.
For now I’ll go with the skeptical attitude that makes me such a hit in social circles around Santa Fe. Looking at it narratively, the claim is essentially promising people something for nothing, which rarely, if ever, plays out in favor of the person believing the claim.
Disregarding the question whether it functions as expected, our editor Garth Clark sees it as a tastefully-designed novelty item. I believe the description he used was “like a tortoise with a fever.” That casts it in a more-adorable light; like a clay pet handwarmer. I could be sold on that angle.
So use your best judgment. Please let us know if you have any deeper insight into this claim and please try not to burn your house down.
Bill Rodgers is a Contributing Editor at CFile
Any thoughts about this post? Share yours in the comment box below.
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I myself made one of these heaters out of ceramic pot. Put together, bolted and experimented by trying one, two, four and then six tea candles. It seems that it would be the same heating amount without the clay pots. They do however give longevity to the heat by means of retaining heat for a time after candles go out. That’s it. So the clay pot idea is little more than candle burning by itself. Much like saying; torch heat an iron rod, then take said rod into a small room and see how well it heats up the area. Not much at all, and it’s cooling time may be slow, but if your freezing and have only candles, do your spouse a favor and don’t ruin her flower pots so your “candles heated” home can be the same temperature if you didn’t make the world’s ugliest space heater our of her pottery. If you are a bachelor, never have company, have no electricity, then it’s just you who’ll know how ridiculous you are. And if that’s the case, you needn’t worry about a spouse in your near future.
For an 8 x 10 ft room with furniture, I was able to heat it with 20 Prayer Candles encased in 10 ” glass containers. The Prayer Candles lasted about 6 days continuous. So Yes you can heat a room with Candles. I would use CAST IRON as my heater core because it seems to hold heat for longer periods of time than the CLay. I would also employ the use of black pipe with a 90 degree angle to assist in pulling cool air through the heated pipe and add to the heating potential by circulation rather than just radiant heat. 20 Candles will produce about as much heat as a 1500 watt space heater.
Hey Bill!
That’s an awefully long winded post about something that you yourself have not tried. Personally I’m looking for a a post from someone who has actually tried it. I’m not necessarily looking for an expert, just someone at who, through their experience has an honest opinion which you do not. Stick to what know or have actually tried. You’ve just waited my time here and I thought I’d let them you know.
IT’s a simple calculation. You will not get any more heat than that which can be created by the fuel. If it is two candles ask a reliable friendly physicist to calculate the most heat – BTU’s – the fuel can produce. It is then simply a matter of determining how long that heat will last in the environment (insulation) over how long. The retention of the heat in the ceramics is useful to prolong the time the heat is available to the environment, but, in the end, will not increase the total BTU as the ceramics itself is not contributing to the BTU, only slowing its dispersal. Soapstone is an even better medium for holding heat.