Most bio-ethanol in India is produced from the molasses left over from the refining of sugar from sugarcane, but the supply of molasses is insufficient and not reliable enough for costly ethanol production facilities that need to keep working around the clock to pay off. There is huge potential in a little-known dryland crop, sweet sorghum, to help fill this supply gap. ‘Sweet’ varieties of sorghum store large quantities of energy as sugar in their stalks, while also producing reasonable grain yields.
Sorghum, like sugarcane and maize, exhibits C4 metabolism – making it more efficient at converting atmospheric carbon dioxide into sugar than most plants. As a dryland crop, sorghum requires far less water than costly irrigated sugarcane, making it more accessible to the poor. The juice squeezed out of sweet sorghum stalks contains about 15-20% sugar that can be fermented into ethanol more cheaply than from sugarcane molasses—and with even greater energy savings compared to maize grain, which has to be hydrated and converted from starch to sugar before it can be fermented.
India’s National Research Centre for Sorghum (NRCS) has developed excellent open-pollinated varieties and some hybrids. ICRISAT’s complementary contribution has been the identification of high-sugar parent lines for hybrid breeding from their global germplasm collection (another payoff from that immensely valuable resource). Hybrids are also less photoperiod sensitive so they can be grown year-round, smoothing out supply variations for the ethanol production facilities.
Making it happen
Public-private collaboration is used to move sweet sorghum from a good idea on the shelf, to impact on the ground. The hybrid sorghum program receives substantial support from the private sector (30 seed companies) through a Hybrid Seed Consortium, so the seeds are moving quickly through the research-to-development pipeline.ICRISAT Headquarters in Patancheru, India has formed a public-private partnership with Rusni Distilleries (P) Ltd. Rusni ensures that seeds of the highest-sugar sorghum varieties identified by ICRISAT and NRCS reach farmers so they can increase their productivity. Rusni also helps farmers by transporting the stalks from farms within a 30 kilometer radius of the plant, and providing more distant farmers with technologies to crush the stalks and reduce the juice into syrup that can be moved cost-efficiently to the ethanol production plant.
Forty percent of India’s oil imports are consumed in the form of diesel fuel, and demand is rapidly growing. The nation has adopted similar blending targets as for bio-ethanol (10%). Bio-diesel is even more environment-friendly than bio-ethanol because it requires less energy to process. It is also much less polluting than fossil-fuel diesel.
As in the case of bio-ethanol, the biggest constraint for takeoff of the bio-diesel industry is insufficient supply of the raw material. To fill this gap, vast wasteland areas, estimated at 38 to 187 million hectares in India, that include areas suitable for dryland-hardy bio-diesel crops can be made available to local communities. While providing an income-earning opportunity for the poor, these perennial tree and shrub crops also help rehabilitate these lands by building the fertility of their soils.
Two contrasting dryland species are especially interesting: Pongamia pinnata, a leguminous tree adapted to wetter wastelands with problem soils; and Jatropha curcas, a more drought-tolerant shrub adapted to well-drained wastelands and widely grown as a homestead boundary plant in the Sahel. Both produce fruits containing about 35% oil suitable for bio-diesel.Women are the main cultivators and processors of bio-diesel crops at the village level. ICRISAT is working with poor women united in self-help groups to start Pongamia enterprises in remote tribal areas of Andhra Pradesh, India, and working with India’s national research system to identify high-oil varieties as well as better cultivation methods.India is also promoting Jatropha; it is grown along rail lines and the oil is blended with petro-diesel to power trains. Japtropha is also widely grown as a hedgerow boundary plant in Indian and African villages.
A future of possibility
Will biofuel crops compete for land with food crops, driving up food prices? To be sure, there are risks; however we look at this issue differently. The dryland poor need food to eat, but they also need opportunities for economic growth if they are to escape poverty. Sorghum production in India has been declining for many years due to urban preferences and subsidies for rice and wheat, lessening economic opportunities for dryland agriculturalists. The same trends will probably develop in Africa in decades to come. Increases in area sown to corn or sugarcane for ethanol, in contrast would take the most valuable, fertile lands out of food production.
We can help transition the sorghum enterprise from a human food to a cash crop for bio-ethanol as well as producing grains and stalks that feed humans and livestock. We can help rural villages gain greater self-sufficiency in energy production through bio-diesel crops. The benefits are multiple and significant: easing poverty, reducing air pollution, mitigating global warming, and rehabilitating degraded wastelands.
Thursday, February 14, 2008
I wish to share the details of a research on biofuels being conducted by ICRISAT(International crops research institute for the semi-arid tropics) in my country India. Contrary to common belief that massive subsidies are needed to promote bio-ethanol, it is now price-competitive with petrol (gasoline) in India without subsidies, due to recently skyrocketing petrol prices. India is targeting a 10% blend of ethanol in its national petrol supply. The constraint is not the cost of ethanol production; it is the supply of raw materials. This is where ICRISAT and partners come in.