Jatropha curcas: poison shrub or environmental savior?

Jatropha curcas is a plant that sounds like science fiction. Proponents’ claims describe it as a biofuel miracle shrub that out-produces corn 10-1, grows in marginal lands, and requires very little water. Its oil can also be used in a Diesel engine with no modifications to the engine or the oil (no transesterification needed). But this bush has a dark side: mildly poisonous seeds (1 or 2 are a laxative, 5 are deadly), the need for harvesting by hand, a propensity to die in the cold, and its perception by some as an invasive weed.

None of those problems have stopped Clint Cheek, a network engineer with biodiesel dreams, from doing everything he can to change careers from computers to curcas. “Jatropha will grow anywhere,” enthuses Cheek in his Texas drawl. “You can go to a parking lot, crunch up 14 tons of concrete, throw on some seeds, and it’ll grow!”

This “grow anywhere” propensity has led Western Australia to declare jatropha curcas an invasive species, making it illegal to grow jatropha for biofuel production. Ron Schwartz of Biosecurity Australia wrote that jatropha had been assessed as posing a significant weed risk in Western Australia. “Based on our information at present it definitely has weed potential,” opines Schwartz Yet, other Australian states have not followed suit in banning jatropha, and Queensland has discussed committing 100,000 hectares (386 square miles) to a model jatropha farm.

India also doesn’t buy into Western Australia’s caution. The Indian government has identified over 300,000 km² (an area larger than Arizona) of jatropha-ready wasteland and has committed 1.3 billion rupees (roughly $26.5 billion) in incentives for farmers to grow jatropha. India aims to replace 20% of its diesel fuel consumption with jatropha oil by 2011, and is already using jatropha extensively in its rail system. India clearly is willing to gamble on the fuel benefits outweighing the invasive weed danger.

Erring on the side of potential benefit over potential cost has burned Americans in the past. Southern residents are constantly reminded of the potential impact of invasive species as they stare at endless landscapes taken over by kudzu. Originally brought to the U.S. to combat soil erosion, kudzu became “The vine that ate the south.”

But Cheek is quick to dismiss the kudzu-to-jatropha comparison. For one, points out Cheek, jatropha’s bush-like qualities make it easier to control than a vine. “Careful management should make it simple to control,” says Cheek.  “In addition,” added Cheek, “It can’t survive any extended temperatures below 40 degrees Fahrenheit, so it can’t grow anywhere that gets a frost.”

That temperature requirement isn’t scaring off Florida farmer Mark Dalton, of My Dream Fuel. For him, the advantages far outweigh the negatives. “Jatropha can go six months without a drop of water. You don’t have to harvest the tree. All you have to do is take the pods off the tree, take the seeds out of the pod, crush the seeds, and you have biofuels.” Claims Dalton, “This tree is incredibly hardy. It can go 6 months without a drop of water.”

In addition, jatropha shouldn’t factor into the “food vs. fuel” debate that has plagued biodiesel and ethanol. “Not being a food source, you’re not competing with corn or soybean or other products that are being used to feed this world’s population,” points out Dalton. Pair that with jatropha’s ability to grow in soil that would make a soybean cringe, and jatropha can be grown with no negative impact on food production.

According to its proponents, jatropha has another advantage: its potential has barely been scratched. “We’re still working with a wild plant. An undomesticated crop,” points out Roy Beckford of the University of Florida. “Even at its very lowest projections, jatropha gives you 200-300 gallons per acre, and soy gives you less than 100 gallons per acre.” Beckford points out a further jatropha advantage: it’s long life. Soy is an annual, meaning it has to be replanted every year. Jatropha bushes live 50 years on average.

One industry has pushed chips in on the jatropha oil card: airlines. Four airlines have conducted live flight tests with a jatropha blend since late 2008: Continental, Virgin Atlantic, Air New Zealand, and Japan Air. All four are banking on jatropha as a future mainstay source for their fuel-thirsty airplanes, and all four have successfully flown on a blend of jatropha and biodiesel in one engine of a multi-engine plane. “They did all the tests, emergency shutdowns and startups,” says Cheek.

“The airplane performed perfectly,” Continental test pilot Rich Jankowski told the Houston Chronicle newspaper. “There were no problems. It was textbook.”

But wait, there’s more! As a crop, jatropha has significant benefits. It plays nicely with other plants and can be planted alongside coffee, sugar, fruits, and vegetables. Jatropha produces a slight scent that dissuades animals from going near it, so it’s often planted as a fence to keep animals away from other crops and can even deter mosquitoes. Its drought tolerance and marginal soil preference makes it an ideal desertification fighter, and its seed cake makes an excellent fertilizer.

Cheek waxes poetic about the potential for other jatropha applications. He points out that in coastal Texas, dredging operations continually produce small islands of near-sludge from the silt. The islands aren’t particularly stable, and certainly not live-able. But, points out Cheek, “Put a small layer on topsoil, plant jatropha seeds, harvest the oil and reuse the seed-cake to fertilize the land. 10 to 20 years from now, they’re viable little islands that you can put buildings on.” Cheek’s enthusiasm so evident that one can almost see his huge grin over the phone as he says ,“I just do not see why people aren’t going crazy about it over here. Every biorefinery in Texas is asking for feedstock: ‘How many millions of gallons per day can you send me,’ they ask. It’s ridiculous.”

Jatropha’s hand is still being dealt, like that of most alternative energy concepts. But with enthusiasts like Cheek and Dalton evangelizing on its behalf, airlines getting on board, and even companies like British Petroleum getting on board (they recently partnered with D1 Oils of London on Indian Jatropha), the potential for jatropha cannot be ignored. It’s a gamble that more and more organizations are taking.