Combustion heat and calorific value of wood versus humidity
Combustion heat and calorific value of wood versus humidity.
Humidity [%] |
Value fuel wood [GJ / t] |
0 | 19,00 |
15 | 15,79 |
20 | 14,72 |
25 | 13,72 |
30 | 12,58 |
35 | 11,51 |
40 | 10,44 |
45 | 9,37 |
50 | 8,20 |
55 | 7,23 |
60 | 6,16 |
If you purchase “by weight” will be performed by the user, which will allow the wood to dry then the calculation can be made as follows in Example 2.
Table. The calorific value of wood – different species.
LP | TYPE
WOOD |
kg/mpu water 25% | kg/mpu fresh wood | l/mpu
evaporated water |
GJ/mpu calorific value |
1 | PLUM | 576 | 10.13 | ||
2 | GRAB | 570 | 700 | 130 | 10.00 |
3 | ACACIA | 530 | 627 | 97 | 9.15 |
4 | MOUNTAIN ASH | 511 | 700 | 189 | 8.98 |
5 | PEAR | 504 | 750 | 246 | 8.86 |
6 | BUK | 490 | 750 | 260 | 8.61 |
7 | OAK | 475 | 715 | 250 | 8.35 |
8 | APPLE | 468 | 700 | 232 | 8.23 |
9 | ASH | 461 | 551 | 90 | 8.10 |
10 | NUT | 459 | 664 | 205 | 8.07 |
11 | ELM | 459 | 594 | 135 | 8.07 |
12 | CLONES | 447 | 679 | 232 | 7.67 |
13 | BIRCH | 440 | 595 | 155 | 7.92 |
14 | CHERRY | 400 | 630 | 230 | 7.03 |
15 | LARCH | 396 | 585 | 189 | 7.30 |
16 | CHERRY | 370 | 585 | 215 | 6.35 |
17 | CHESTNUT | 367 | 630 | 263 | 6.30 |
18 | Douglas fir | 367 | 490 | 127 | 6.61 |
19 | PINE | 353 | 574 | 221 | 6.50 |
20 | ASAP | 324 | 567 | 243 | 5.70 |
21 | SPRUCE | 310 | 560 | 250 | 5.84 |
22 | POPLAR | 309 | 525 | 216 | 5.30 |
23 | FIR | 300 | 595 | 295 | 5.53 |
24 | WILLOW | 238 | 610 | 372 | 4.01 |
explanation to the table:
– mpu is the cubic meter of stacked timber (fireplace),
– water 25% to 25% wood moisture,
– fresh wood to unseasoned wood, immediately after cutting,
– evaporated water to amount of water that needs to be evaporated from fresh wood, do optimal level 25% humidity 1 wood (need to put approx 10% wood shrinkage, so about these 10% more wood needs to be dried and water evaporated from it as well)
– Calorific Value to calorific value 1 mpu,