ENERGETIC VALUE OF JATROPHA
energetic value of jatropha
| Composition of Jatropha Fruit and fraction by weight |
|
|
|
|
in % of fruit weight |
in% of seed weight |
assumed fruit weight of 1,538g |
| Shell |
35% |
N.A. |
538 |
| Seed |
65% |
N.A. |
1,000g |
| Husk |
29% |
44.6% |
446g |
| Kernel |
36% |
55.4% |
554g |
| Oil |
|
|
|
| a) Expelling ratio of 25% |
16% |
25% |
250g |
| b) Expelling ratio of 34% |
22% |
34% |
340g |
| Seedcake |
|
|
|
| a) Expelling ratio of 25% |
48.8% |
75% |
750g |
| b) Expelling ratio of 34% |
43% |
66% |
660g |
Depending on the expelling efficiency of the hardware, 1 metric ton of seeds will produce between 250 and 340 kg of Jatropha crude oil. With a density of 0.91kg/l (in comparison to mineral diesel with a density of 0.84kg/l), this translates into a yield of 275 to 374 l of CJO per MT of seeds.
Based on an average harvest of 7 MT of seeds per ha, a single ha of jatropha plantation will yield 1,750 to 2,380 kg of CJO, equaling 1923 to 2,615 l per ha.
| Energy Value of Indivisual Jatropha plant components SpecificEnergy Density by mass in Mj/kg |
|
|
|
|
Mj/kg |
|
Calculated for sample of 1538g of fruits (1000g of seeds) |
| Jatropha plant |
15.5 |
|
|
| Fruit |
21.1 |
|
32.4 |
| Fruit Shell |
10 |
|
5.38 |
| Husks |
17 |
|
7.58 |
| Seeds |
21-23 |
|
|
| Scenario l: Low expelling efficiency (25%)/seed weight to oil ratio 4:1 |
|
|
|
| Seed Cake (incl. husks) (750g) |
21 |
|
15.75 |
| Oil (250g) |
45 |
|
11.25 |
| Scenario ll: High expelling efficiency (34%)/seed weight to oil ratio 3:1 |
|
|
|
| Seed Cake (incl. husks) (660g) |
17 |
|
11.25 |
| Oil (340g) |
45 |
|
15.4 |
Gross energetic value
Once the oil is extracted, about 66 to 75 % of the original seed weight remains as seed cake residue, mainly in the form of protein and carbohydrates. The amount of oil left in the seed cake depends on the extraction process.
| 1. Expelling ratio 4:1 |
|
|
| a. Energy content Jatropha Crude Oil: |
11.25 Mj/kg |
= 35% |
b. Energy content of remaining non-oil biomass
(seed cake + fruit shells) |
21.15 Mj/kg |
= 65% |
| 2. Expelling ratio 3:1 |
|
|
| a. Energy content Jatropha Crude Oil: |
15.4 Mj/kg |
= 48% |
b. Energy content of remaining non-oil biomass
(seed cake + fruit shells) |
16.8 Mj/kg |
= 52% |
Energetic value
The energy content of the remaining parts of the fruit after oil extraction exceeds the energy content of the oil
Energy conversion and value formula per 1 ha of jatropha plantation:
| A) Oil component |
|
|
|
| Step 1: 7 MT of seeds/ha |
x |
expelling ratio of 30% |
= 2,100 kg of CJO/ha (= 2,307 l) |
| Step 2: 2,100 kg of CJO |
x |
45MJ/kg |
= 94,500 MJ (= 94.5 GJ) |
| Step 3: 94.5 GJ |
/ |
6.1 boe/GJ |
= 15.5 boe |
| Step 4: 15.5 boe |
x |
75 USD/bl |
= 1,162.5 USD |
| B) Seed cake component |
|
|
|
| Step 1: 7 MT of seeds/ha |
x |
expelling ratio of 30% |
= 4,900 kg seed cake/ha |
| Step 2: 4,900 kg seed cake |
x |
21MJ/kg |
= 102,900 MJ (= 103 GJ) |
| Step 3: 103 GJ |
/ |
6.1 boe/GJ |
= 16.9 boe |
| Step 4: 16.9 boe |
x |
75 USD/boe |
= 1,267.5 USD |
C) Combined energy value
94.5 GJ (oil) + 103 GJ (seed cake) = 197.5 GJ
oil to seed cake ratio
| D) Combined commercial value |
|
|
|
| 15.5 boe |
+ |
16.9 boe |
=32.4 boe |
| 32.4 boe |
x |
75 USD/boe |
= 2,430 USD |
Computation for 20, 000 ha plantation:
- 1,890,000 GJ (oil)
- 2,060,000 GJ (seed cake)
- Total: 3,950,000 GJ
- = 647,540 boe
