Farmers may soon be growing a new type of energy crop, called high-biomass sorghum, that can be used to generate electricity or fuel cellulosic ethanol plants.
That’s according to Brent Bean, former Texas A&M research and Extension grain specialist and now director of agronomy at NexSteppe, a seed company that specializes in energy sorghums.
The company’s high-biomass sorghum is sold under the Palo Alto brand. Currently, one hybrid, N52K1009, is available, and more will be released this year, Bean told those attending the mid-December 2013 Western Alfalfa & Forage Symposium.
The hybrids typically grow between 12’ and 16’ tall and produce a great amount of biomass low in soluble sugar and typically “10-15 percentage points drier than a forage sorghum would be at harvest.” The lower moisture content reduces harvesting and transportation costs and gives the crop a higher energy density, says Bean.
The crop can be grown on marginal land, although it will yield better on productive ground. It will likely be harvested and stored as hay or silage, he adds. In a recent Oregon study, yields averaged 10 dry tons/acre under irrigation, with a yield range of about 6-13 tons, depending on the hybrid.
The annual’s establishment costs are “relatively low,” he says, and fertilizer inputs may be lower than those for forage sorghums. Seed will cost around $55/acre.
NexSteppe is currently working with companies in the U.S. to determine if high-biomass sorghum can be used as a replacement for coal at utility plants. Bean also sees it as a good fit for farmers who will, in the future, grow feedstocks for cellulosic ethanol plants, along with perennials such as miscanthus and switchgrass.
“With sorghum, you can be in and out in 140 days, and I think farmers will be a lot more receptive to that than planting a perennial that will require long-term commitment of the land for several years.”