Jatropha: hedging bets?

If you have ever taken a train between Mumbai and Delhi, you will have meandered through mile after mile of sprawling wasteland carpeted with rapacious, poisonous weeds. Yet these ugly shrubs may prove to be the ideal biofuel crop. 

Excitement is growing over the potential of the perennial jatropha bush as an alternative fuel. Jatropha produces fat, golf-ball-size seeds, which can be crushed to obtain a corn-coloured liquid similar to palm oil that can be made into biodiesel for combustion in standard diesel engines.  The residue can also be processed into biomass to power electricity plants.

Plenty of plants can be processed into fuel, but it takes vast swathes of land, hours of labour, gallons of water and pots of agrochemicals to do so. Jatropha thrives even in pest-ridden and drought-stricken areas, does not thirst for water or fertilizer and is not edible. Thus it does not divert resources away from crops that could be used as foodstuffs. It also yields more than four times as much fuel per hectare as soybean, and more than ten times that of corn.

If the crop does have a future, it is on the subcontinent:

• The Wall Street Journal recently reported that farmers in the United States only have enough arable land to replace about 7% of the country's gasoline with corn-based ethanol, despite an ambitious renewable-fuels target of 15%, by 2017.
• India, by contrast, has millions of acres of wasteland with low water tables and poor quality soil. The Indian government intends to start mixing 5% of jatropha into diesel by 2007.

Sizeable plantations of jatropha are also being developed in Zimbabwe, Egypt, China, the Philippines and Malaysia, in the hope that jatropha will help them to become more energy independent and even export biofuel.

Caveat agricola?

Agronomists urge caution, acutely aware that several plants that have promised to be 'solutions' have turned into environmental and social disasters. The biggest risk with this plant is that it will not be economically viable:

• Farmers may see jatropha as more valuable than food crops, lowering a country's food production.
• A recent United Nations report on biofuels warned that the benefits to farmers were "not assured", as commercialisation of the crop can take years.
• Biofuel programmes may result in a "concentration of ownership", driving poorer farmers off their land and into greater poverty.
• According to the New York Times, Indian farmers are already frustrated by poor seed sales after being encouraged to plant hedgerows of jatropha.

See more blog discussion here.