Written by Rick Da Tech
Pongam tree aka, Pongamia pinnata, Millettia pinnata, Pongamia, Honge tree, Karanj tree, and Indian Beech tree is a deciduous legume that grows up to about 50 to 80 feet tall and is native to subtropical regions. It is a viable non-toxic alternative to jatropha. Being a legume, it fixes nitrogen into the soil and is often used as a windbreak between fields on farms.
It has a wide spreading canopy making and fragrant flowers making it ideal for ornamental shade applications. The oil is non-edible due to bitter tasting flaveroids. The plant has pharmacutial uses but is not poisionous to the touch like jatropa. It is insect resistant and there is mention of using the presscake as both insectiside and chicken feed.
The plant prefers wet and hot with well drained soil, full sun to partial shade, and temperatures above freezing, as the plants are not cold hardy. A 15ft x 15ft spacing is prefered.
The Asian varieties reach adult height in 4 or 5 years and start bearing seads at 4 to 7 years. It can produce 50 to 100 lbs of seed per tree. Assuming 200 trees per acre, and 25% oil per pound of seed you would get from about 100 to 600 gallons of oil per acre. Genetically modified plants produce more.
The tree is all over India, used to line roadways and waterways. The seeds can be economically picked up from these plants and the oil expelled in presses in local villages for small quanities of oil that can either be added to diesel used by the village or sold for an income. The meal can be used as animal fodder or composted.
Its disadvantage is that the oil may contain high levels of unsoponifable material. More literally, the oil contains stuff that will not turn into biodiesel. Sometimes a lot of stuff that will not turn into biodiesel.
Fatty acid composition:
palmitic, 3.7–7.9%, c16:0
stearic 2.4–8.9, c18:0
arachidic 2.2–4.7, c20:0
behenic 4.2–5.3, c22:0
lignoceric 1.1–3.5, c24:0
oleic, 44.5–71.3, c18:1
linoleic 10.8–18.3, c18:2
eicosenoic 9.5–12.4%. c20:1
Karanj (Pongamia pinnata)
Performance and emission characteristics of a 4 stroke C.I. engine operated on Honge Methyl Esters using artificial neural network by Shivakumar, Srinivas Pai P., Shrinivasa Rao B. R. and Samaga B. S.
Pongamia oil - a promising source of bio-diesel by P. Gogoi. D.R. College, Golaghat , Assam
Purdue Univ. Horticulture Dept
Austrailian plant supplier, (genetically modified)
Plants of Hawaii - Milletia pinnata (pongamia)