Sweet Sorghum Produces Renewable Diesel

Joanna Schroeder

Ceres’ sweet sorghum hybrids have been successfully processed into renewable diesel by Amyris.  The pilot-scale project was part of a grant from the U.S. Department of Energy (DOE) and Amyris presented a summary of results during the 34th Symposium on Biotechnology for Fuels and Chemicals held in New Orleans, Louisiana.

The project evaluated both sugars and biomass from sweet sorghum hybrids grown in Alabama, Florida, Hawaii, Louisiana, and Tennessee.  Once harvested, the sorghum juice was extracted from its stems and concentrated into sugar syrup.  Next, the syrup was processed by Amyris at its California pilot facility using its yeast fermentation system that converts sugars into Biofene.  From there, the Biofene can be processed into renewable fuels and chemicals.

“We believe that sweet sorghum could be an important and complementary source of fermentable sugars as the U.S. expands the production of renewable biofuels and biochemicals through the use of non-food crops outside of prime cropland,” said Spencer Swayze, Ceres director of business development.

Spencer believes that with free sugars in sweet sorghum readily accessible larger quantities of low-cost sugars could become available.  Ceres says that sweet sorghum has a number of advantages:  it’s fast growing, requires less fertilizer than sugarcane, can be grown in drier climates and produces large amounts of fermentable sugars and biomass.

Todd Pray, Amyris director of product management said, “The results from these evaluations confirmed that the Amyris No Compromise renewable diesel production process performs well across different sugar sources. Ceres’ sweet sorghum hybrids produced sugars that yielded comparable levels of farnesene as sugarcane and other sugar sources Amyris has utilized.”

Biodiesel, biomass