Sorghums — grain, sweet and forage — offer unique opportunities as efficient, adaptable and drought tolerant feedstocks for biofuel production.
“Sorghum can fit into all renewable fuel schemes,” said Tim Lust, CEO, National Sorghum Producers, during the International Conference on Sorghum for Biofuels in Houston. “This conference is exciting,” Lust said. “It gives us an opportunity to understand the scope of global research.”
He said sorghum has been around for many years, “but a lot of the world does not know about it.” As a potential renewable fuel source, he said sorghum offers several options: as a starch for ethanol, sweet sorghum as sugar to ethanol, and forage and sudangrasses as high tonnage biomass for cellulosic or ligno-cellulosic ethanol.
Lust said 20 percent of the current U.S. sorghum crop goes into ethanol production. “And more (ethanol) plants are coming online in the sorghum belt. We see a lot of opportunity to expand.”
Lust presented a SWOT (strengths, weaknesses, opportunities and threats) analysis of sorghum as a biofuel crop.
Strengths include drought tolerance. “Sorghum, by nature, is drought tolerant,” he said. “That provides a unique opportunity.” Studies in West Texas show sorghum can produce significant tonnage on relatively small amounts of water.
“It’s also adaptable. Sorghum bicolor (the most common sorghum) will grow in 80 percent of the world.”
He said the sorghum genome has recently been sequenced, “the second cereal to be sequenced. We now have tools available (for enhanced research).”
He said seed companies have diverse germplasm and farmer checkoff funds, recently approved, provide more research money.
“Sorghum has well-known agronomic traits and we understand the disease and insect threats. It’s a non GMO crop and we have an active public research sector.”
He considered weaknesses, too.
“Growth will demand investment from private industry,” he said. That investment may be stymied by consolidation of the seed industry. Current GMO-centric research also affects distribution of research dollars.
Potential reduction in grain acreage in the United States is a possible weakness. “Also, we have limited research on sorghum as a biofuels crop and no ethanol-specific grain sorghum hybrids.”
Opportunities, he said, are “tons, tons and tons. We need a lot of feedstocks for biofuels and yields will be critical. Sorghum offers an opportunity to deliver tons of biomass on a limited amount of water. Sorghum can withstand conditions with either limited water or too much.”
Lust said a new generation of researchers and entrepreneurs offers potential for improved opportunities for sorghum as a renewable fuels crop. “Increased acreage worldwide is another advantage. Sorghum can be part of an international solution to renewable fuels.”
He said an advanced definition of biofuels in the energy bill “makes sorghum unique. It also leaves a small carbon and nitrogen footprint. We’re just learning about the compositional analysis of biomass.
“New sorghums have the potential to be some of the great biofuels crops,” he said. “Sweet sorghum could double the gallons per acre when combined with cellulosic or ligno-cellulosic ethanol.” That’s accomplished by using the sweet sorghum sugar extraction for ethanol and then using the biomass for cellulosic conversion.
Threats include other alternative fuel sources that emerge with high energy prices. “We also face the food-versus-fuel debate,” Lust said. “We have to position sorghum as part of the solution.”
Government renewable fuels standards policy changes also could threaten ethanol production. “The credit crunch might limit funding from private industry,” he said. “We have a limited number of new facilities.”
The logistics of harvesting, storing and transporting grain sorghum also must be considered. “And we have only 35 or 40 sorghum breeders in the United States and worldwide. We need more resources to develop feedstocks.”
He’s optimistic. “We see a tremendous potential for biofuels. And water issues make the renewable fuels industry lean toward crops that use water more efficiently. Sorghum offers low production costs, drought tolerance and potential to grow on 80 percent of the world’s crop land.
“We expect significant new acreage of sorghum.”