BTU ratings of exotic woods?

[Jake]

Anyone have anything for IPE, JATOBA, CUmaru, Cabriuva or anything simmiliar?

In comparing
the firewood btu chart
http://www.chimneysweeponline.com/howood.htm

to the
Janka hardness scale
http://www.woodfloorsonline.com/techtalk/hardns.html

the denser(harder) the wood, the more BTU... But how much?

 

[Jags]

I would think that anything harder than Osage orange would require magnesium fire starters. :lol:

Some woods such as palope wood is so hard it actually has a fire (retardant) rating. Doubt that much of this stuff would be fit for our wood burners, or burning in general, therefore, doubt if much exists for btu data.

 

[Corey]

The answer may surprise you.

Generally - all wood has about the same BTU per pound ~8600 for bone dry wood. "Seasoned wood" is considered to have about 20% moisture on average and about ~6400 BTU per pound.

In looking at the table on the chimneysweep.com page, you see a lot of different BTU's and a lot of different weights per cord of wood, but when you start dividing the numbers out, one number keeps popping up....~6400 btu per pound. In fact, many btu/cord tables are constructed this way. The 128 cu ft cord of wood is assumed to contain about 85 cu. ft of solid wood, the density of that species is used to get the weight of 85 cu. ft. and multiplied by 6400 BTU per pound.

So back to the question, the exotics contain about 8600 BTU per pound of dried wood, 6400 BTU per pound of average "seasoned" wood. It is all cellulose in the end!

Corey

 

[Jags]

The answer may surprise you.

Generally - all wood has about the same BTU per pound ~8600 for bone dry wood. "Seasoned wood" is considered to have about 20% moisture on average and about ~6400 BTU per pound.

In looking at the table on the chimneysweep.com page, you see a lot of different BTU's and a lot of different weights per cord of wood, but when you start dividing the numbers out, one number keeps popping up....~6400 btu per pound. In fact, many btu/cord tables are constructed this way. The 128 cu ft cord of wood is assumed to contain about 85 cu. ft of solid wood, the density of that species is used to get the weight of 85 cu. ft. and multiplied by 6400 BTU per pound.

So back to the question, the exotics contain about 8600 BTU per pound of dried wood, 6400 BTU per pound of average "seasoned" wood. It is all cellulose in the end!

Corey

Corey, you can be on my team for a game of trivia anytime. :cheese:

 

[Jake]

The answer may surprise you.

Generally - all wood has about the same BTU per pound ~8600 for bone dry wood. "Seasoned wood" is considered to have about 20% moisture on average and about ~6400 BTU per pound.

In looking at the table on the chimneysweep.com page, you see a lot of different BTU's and a lot of different weights per cord of wood, but when you start dividing the numbers out, one number keeps popping up....~6400 btu per pound. In fact, many btu/cord tables are constructed this way. The 128 cu ft cord of wood is assumed to contain about 85 cu. ft of solid wood, the density of that species is used to get the weight of 85 cu. ft. and multiplied by 6400 BTU per pound.

So back to the question, the exotics contain about 8600 BTU per pound of dried wood, 6400 BTU per pound of average "seasoned" wood. It is all cellulose in the end!

Corey

Damn... Thats the answer I was looking for.


Thank you

 

[DeanBrown3D]

Its actually surprising that pine has a higher energy value (albeit only slightly) than most hard woods, on a per-pound basis. The creasote and oils that make it so infamous have a higher heat content than dryer cellulose type woods.

But heat content isn't everything.

 

[Corey]

If the difference is very small, it may simply be due to rounding of number. For example on the chimneysweep page;

Ponderosa Pine 15.2MBTU/cord divided by 2,380 lb per cord = 6387 btu/lb
White Oak 25.7MBTU/cord divided by 4,012 lb per cord = 6405 btu/lb

So a little rounding here and there and the numbers are practically identical.

Corey

 

[Elderthewelder]

Its actually surprising that pine has a higher energy value (albeit only slightly) than most hard woods, on a per-pound basis. The creasote and oils that make it so infamous have a higher heat content than dryer cellulose type woods.

But heat content isn't everything.

Ironically I just picked up 2 truck loads of pine rounds after work today, I was a little hesitant, my co worker and fellow wood burner had seen the down and sectioned tree from a distance and thought it was Alder, 3 days later we went and got it and it was a big pine that came down during our wind storm a couple weeks ago, came down in a city owned play field, city sectioned it up and left it, so we just had to take it, scored 3 truck loads of Alder the same way last week

 

[Jake]

I put a chunk of cumaru in at 930... its 1am right now and I have 1/2 of it left. I layed it on hot coals, got it flaming, then dampered down

It was 5"x 6" x15" and probably weighed about 8lbs

I dont think a simmiliar piece of anything domestic would last that long.... I'm going to keep experimenting