Google “jatropha,” specifically the species Jatropha curcus, and it’s hard to miss the hundreds of Web sites touting it as the new darling of the biodiesel world.
While jatropha’s seeds are toxic enough to require special handling, they are between 40 and 60 percent oil, making the tree a potentially high-yield source of biodiesel. One hectare of jatropha (roughly 2.5 acres, or an area about one and a half times the size of a soccer field) produces an estimated 500 gallons of biodiesel, nearly four times the 130 gallons a hectare soybeans produce.
The biodiesel blends produced from jatropha seeds can be used in all forms of diesel-based transportation — as shown in January when Air New Zealand flew a 747 with a 50/50 blend of jatropha biodiesel and regular jet fuel in its tanks. Byproducts of the biodiesel production include useful things like fertilizer, paper, cosmetics and even cough medicine.
Jatropha may emerge as one of the most viable biodiesel sources because it’s able to grow in marginal, low nutrient, even gravelly soils where most commercial crops — including biodiesel competitor corn — struggle.
Native to Central America, jatropha prefers warm climates like those of India and Brazil, and while it likes about 2 feet of rain a year (about the same as corn), it can withstand up to three years of drought by simply dropping its leaves. Also, because the trees can produce seeds for up to 50 years, the erosion problems associated with annual replanting of corn or soy beans are minimized.