Menu
By:
Filters
What's new

Ok Smart TAB'ers Does this Work?

tr1age

tr1age

Administrator
Staff member


From the comments there are some brainy people discussing it, one says it will work because of the fact that it stores heat and disperses at a rapid rate, another says no because a tea light still only has a specific amount of heat it can disperse over time, thus making this no different than lighting a candle and leaving it there.

So smart TAB members, what do you think?

@Corvus Rex perhaps you can shed some light :p
 
Interesting concept. I'm not sold on the science behind it. It will give off a good amount of warmth but its possible because his room is so small that it feels like it is heating it.

I'd give it a try here but I don't have a room that sized and it's just an invitation for my cats to jump up and knock it over.
 
From looking solely at the picture preview of the video (getting a slight gist of what's going on), the first two things that come to mind are...

Tea Kettles
Pressure Cookers

Even with heat being constant output, it's being altered by condensing the area it can heat up directly, causing a "release".

But like I said, I haven't watched the video, so I could be literally taking a crack at something that has nothing to do with what I think it is. But hey, that's my gamble....
 
It's causing convection. However a tea light can only store so much energy. So it is arguably the same heat being dispersed as if you could put a small fan over the candles. Just being stored and released at a hotter temp.


Sent from my iPhone using Tapatalk
 
I want to know what made him even think of trying this. I've got all of those components lying around my home but I'd never think to combine them to heat my room.
 
a candle has a certain amount of fuel that when burned will generate heat, however not very much. putting pots over it will not change the heat output at all however with the setup he has it will help move the air is being heated by the candles to help disperse the heat. however this does not increase the amount of heat the candles are generating. for this solution to work you would have to have either a extremely well sealed room with lots of insulation or simply only be trying to raise the temperature of the room very slightly. because of this if you compare the heat generated to the cost rather then simply saying that it is enough to heat the room suddenly it would seem much less economical. there is a reason we don't heat our houses with lots of candles... (it is not efficient)
 
Here is how I see it.
What this is really doing is trading time for heat. Not only that, since the ceramic is much more efficient at storing and radiating heat than a flame, the heat stays in the hotter state for longer, thus warming the air around it for a longer time than a naked flame would.

tr1age said:
However a tea light can only store so much energy
Click to expand...
Yes the tea light only has so much energy, but in a normal setup, i.e. no pots, that energy dissipates super fast because the space it releases into is large. Its like filling a swimming pool with a cup of water at a time.

This is why
tr1age said:
So it is arguably the same heat being dispersed as if you could put a small fan over the candles.
Click to expand...
wouldn't follow.

Now when you put the small pot over the candles the volume of air that needs to be heated to equilibrium is much smaller. Think filling a pitcher with a cup of water at a time.

While the candle(s) can only give out a small amount of heat per second, the ceramic pot can absorb and store many times that amount per second. Once it hits an equilibrium of the amount of heat it can store vs the heat being sapped from it from outside air then it will no longer get hotter. However, since the pot can store more heat than a candle flame (for a longer period of time) and it has more surface area to dissipate that heat it will output more heat than the candle. Put a second bigger pot on top of it and you get the same process over again.

In effect the pots will absorb the candle heat over time until they get hot enough to pass that heat on. Bigger pots hold more heat so they are kind of multiplying the output by saving all the little pieces of heat to give it to you later in one big bunch.
 
ThatOneGuy said:
In effect the pots will absorb the candle heat over time until they get hot enough to pass that heat on. Bigger pots hold more heat so they are kind of multiplying the output by saving all the little pieces of heat to give it to you later in one big bunch.
Click to expand...

the problem with this setup is the end goal is to heat the air in the room, and while a pot has more thermal value you are just adding an extra step to transfer the heat to the air. adding more steps in-between the candle producing heat, and the heat heating the air make no difference except to change how quickly or slowly the heat is transferred to the air. so no additional heat is being created by using this setup vs. just lighting the same candles.
 
Subtle said:
the problem with this setup is the end goal is to heat the air in the room, and while a pot has more thermal value you are just adding an extra step to transfer the heat to the air. adding more steps in-between the candle producing heat, and the heat heating the air make no difference except to change how quickly or slowly the heat is transferred to the air. so no additional heat is being created by using this setup vs. just lighting the same candles.
Click to expand...
True no new energy is created, but this setup is a more efficient way of turning the energy of burning a candle into a centralized heat source. Not only that, a person will be able to feel that heat source from the pots way easier than candles making their perception of the room warmer than the thermostat actually shows.

As you stated before it is important to have a closed room with no drafts to make this effective at all, and the room temp will only be raised by a few degrees at most for a small room.

However, the ability to feel the heat from the pots and the few degrees that it actually raises the temp are usually enough to make it worthwhile to the person using it. Not to mention those candles are like only 2 cents each.
 
Here is a vid with the math behind the flower pot heaters. This guy figured out that the flower pot heater puts out about 2 btu per minute for 4 hours. He was doing it for a greenhouse to raise the temp 20 degrees over the outside temp with a large space and discovered it would take 134 heater setups, or about 540 candles. For a smaller room and a lower degree change you would probably be able to get 2 or 3 degrees of change for 1 or 2 heaters.


if you really want to find a more efficient way to heat a room and are willing to drill some holes in your walls check this out. It's solar and convection
 
A good way to see if this has any effect would be to use thermal infrared to see how the heat is dispensed?
 
I found a 1500W heater for about $40. It would cost about $1.38 a day to run for 12 hours, generating 5100 BTUs/hr.

From tea lights, you would need about 17 burning to generate that amount of heat. High end estimates put the life of a tea light at 6 hours. Based on a bulk price I found, each candle costs 12.5 cents. So the same amount of heat would be generated for about $4.25 a day, not including the one time cost of the pots and the recurring cost of matches. Not the mention the added risk of burning your house down.

In other words, not only is an electric heater more efficient, it also costs less over time.
 
You also have to remember, there's two types of "heat". (Paraphrasing here)

Most of the heat coming off the candle is convective. It is the air burned in the reaction of the flame, and air directly touched by the flame. This 'heat' tends to rise quickly to the roof where you aren't likely to feel it. So most of that heat energy is wasted.

Putting the ceramic over the flame allows a lot of that convective heat to get transferred to the ceramic. This allows a much greater amount of heat to be turned into thermal radiation, which is radiated outward in all directions. This is why you put rocks around a fire, the rocks catch convective heat, and radiate it outwards, making the fire much more effective at warming the area around it.
 
You must log in or register to reply here.
Top Bottom