Is a oven gas flame 100 percent efficient ?

100% tasty.:vs_cake::biggrin2:

Efficiency ratings for furnaces are the percentage of heat going into your house vs out the chimney not the actual flame.

There are combustion tests for adjustable burners. If you like science or need a cure for insomnia read on. Nothing much to adjust on a oven.

http://www.trutechtools.com/Understanding-Combustion-Efficiency_c_261.html

Before looking at the link I suspected stoichiometry would be mentioned and I've dealt with that subject.

But when stoichiometry isn't necessarily the objective it seems the oven would be above the gas flame efficiency with flue temperature by a considerable margin depending largely on the flue temperature of those units.

That's All Folks

No, its still not 100% efficient.

If it's direct fired, like stove tops it's technically 100% efficient. This is considering the heat transferred into the heated medium. (Air) Measuring the heat transfer into the heated product would indeed be interesting. This would be much less then 100% efficient, and be highly dependent on pan/pot type/material/size and what's actually being cooked.

Cheers!

We use electric ovens where I am. 100% efficient.:glasses:

I believe they are mostly vented into the living space. So if you have a good flame I would think 100% or pretty darn close to it.

yuri said:

100% tasty.:vs_cake::biggrin2:

Efficiency ratings for furnaces are the percentage of heat going into your house vs out the chimney not the actual flame.

There are combustion tests for adjustable burners. If you like science or need a cure for insomnia read on. Nothing much to adjust on a oven.

http://www.trutechtools.com/Understanding-Combustion-Efficiency_c_261.html

Click to expand...

Good read....

Cheers!

supers05 said:

If it's direct fired, like stove tops it's technically 100% efficient. This is considering the heat transferred into the heated medium. (Air) Measuring the heat transfer into the heated product would indeed be interesting. This would be much less then 100% efficient, and be highly dependent on pan/pot type/material/size and what's actually being cooked.

Cheers!

Click to expand...

Sorry. Since non of the latent heat is recovered/transferred, it is not 100%. Roughly 14% of the heat/BTUs of the combusted gas is latent. And unless the moisture is condensed, you don't get that heat.

You haven't lost that energy until it leaves the space being heated. In this case the oven. Some of the extra humidity may indeed be absorbed into the food. The 100% only considers the energy put into the medium over the energy available. As I said, although mathematically true, it's not really an accurate number since it doesn't consider the process involved. This includes but is not limited to the energy lost to venting, and heat lost through the oven walls, during the prolonged heating of the food. Leaving you much more correct.


BTW I've seen some sources mention 11% for NG condensation. I'll try to look them up.

Cheers!

There's also the excess air cooling the flame.

also once energy is gone, it's gone. use it wisely, it's finite.

user_12345a said:

There's also the excess air cooling the flame.

also once energy is gone, it's gone. use it wisely, it's finite.

Click to expand...

You can neither create nor destroy energy. You can only change its form.

user_12345a said:

also once energy is gone, it's gone. use it wisely, it's finite.

Click to expand...

I would say energy is about as finite as our known universe.

...once not locked/stored chemically or otherwise anymore and released in to the atmosphere, it dissipates, eventually outside of the atmosphere to be never used for productive work by us again.

Even combusted natural gas doesn't leave the atmosphere.

Burning hydrogen and oxygen together forms water. Water is separated to give hydrogen and oxygen.

We have a finite amount of energy stored as liquid. But we have solar energy until the sun dies.

Heat leaves the atmosphere. the byproducts of combustion don't.

Figure out a way to artificially recombine the products into fuel efficiently, driving the process with heat from the sun and we'd be set. will never happen.

user_12345a said:

Heat leaves the atmosphere. the byproducts of combustion don't.

Figure out a way to artificially recombine the products into fuel efficiently, driving the process with heat from the sun and we'd be set. will never happen.

Click to expand...

Don't have to. Plants do this quite nicely for us. It just takes a long while to change to something that we currently use. The solar capture is still there, we'll just have to find different ways of using it.

Cheers!

user_12345a said:

Heat leaves the atmosphere. the byproducts of combustion don't.

Figure out a way to artificially recombine the products into fuel efficiently, driving the process with heat from the sun and we'd be set. will never happen.

Click to expand...

I ascribe to a little more optimistic view of our future in regards to energy, power generation and our supply of natural resources. We are still in the midst of a technological revolution with no end in site. I believe we will have clean efficient energy long before our supply of gas and run out.

newer technology to date has lead to fracking, some slightly more efficient solar panels, inverters, but not much else.

efficient synthetic storage in hydro-carbon form with a positive energy return on investment would be needed.

don't think we'll ever see fusion, thorium.