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Home Fire Prest Logs takes the stack out of your firewood!
| Comparison of Heat Output from Wood Fuels |
| Wood Needed to Throw Out 1,000,000 BTU
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| Firelogs or Wood Species |
Home Fire
Prest Logs |
Hickory |
Oak |
Maple |
Alder |
Pine |
| Volume to Produce 1,000,000
BTU's (yd³) |
0.0730 |
0.1815 |
0.2299 |
0.2454 |
0.3130 |
0.3467 |
| Specific Gravity [1] |
1.28 |
0.64 |
0.60 |
0.56 |
0.44 |
0.36 |
| Density (lbs/yd³) [2] |
1687 |
801 |
751 |
701 |
552 |
451 |
| BTU/lb [3] |
8,126 |
6,894 |
5,802 |
5,824 |
5,800 |
6,407 |
| Efficiency [4] |
[5] 94% |
80% |
67% |
68% |
67% |
74% |
| Weight to produce 1,000,000 BTU's (lbs) |
123.08 |
145.35 |
172.69 |
172.05 |
172.78 |
156.39 |
| Weight of One Full Cord (lbs) [6] |
8000.49 |
3799.45 |
3561.57 |
3323.47 |
2617.98 |
2142.01 |
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Specific Gravity is based on
weight when ovendry and volume at 12% moisture content. Water has
a specific gravity of 1. Anything value lower than one floats, any
value over 1 sinks in water.
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Density is computed at the
specific gravity indicated and at 12% moisture content.
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BTU/LB is the amount of energy
or heat released from one pound of wood.
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Efficiency is expressed as
a percentage of ovendry wood equal to 8,618 BTU/lbs.
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Home Fire Prest Logs efficiency
are calculated at 12% moisture content. Although manufactured from
stock containing 10% moisture or less, the logs will absorb some moisture
under normal storage conditions. Burning efficiency is considered
96%/± 2%. The most conservative rating was used in this comparison.
Cordwood species are considered at 20% moisture content, since this
is the average moisture contained in "air-dried" cordwood. Air-dried
wood is defined as having been exposed to air in a yard or shed, without
artificial heat. It has 20% moisture in terms of ovendry weight, or
16.7% in terms of total air-dry weight.
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Cord Weight - Although Home
Fire Prest Logs aren't sold by the cord, it is interesting to compare
the weight with standard species. A cord measures 1.3342 X 1.3342
X 2.6684 yards and is a dimensional measure. A better standard would
be weight since it is the only uniform measurement. As one can readily
observe from the figures and the drawing above, heat values correlate
more consistently with weight than with cube measurements.
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