Pinal Energy explores sweet sorghum ethanol production

By Kris Bevill | October 04, 2011

Pinal Energy LLC has constructed a pilot plant next to its 50 MMgy corn/milo ethanol plant in Maricopa, Ariz., to test sweet sorghum production processes. The project is a joint venture with the University of Arizona to explore the viability of using sweet sorghum, a locally available feedstock, for ethanol production, according Pinal Energy General Manager Keith Kor.

Plant officials expect the first load of 6,000 gallons of sorghum juice to be delivered to the pilot plant this week and stored in two tanks at the plant until it is used for testing. The sorghum juice used at the facility is being sourced from a nearby test plot of sweet sorghum, Kor said.

The primary interest in testing sweet sorghum as an ethanol feedstock is its availability in Arizona compared to corn and milo, according to Kor. Additionally, while corn typically yields 300 gallons of ethanol per acre, sorghum has the potential to yield up to 900 gallons per acre, he said. Sorghum stalks could also be used for animal feed and Pinal Energy will also explore using the sorghum bagasse as a feedstock for biomass boilers.

The plant was constructed in about six months at a cost of about $250,000. Pinal Energy and the university will collaborate on technology used at the pilot plant and expect the project could become an ongoing research facility. Kor said it is possible the pilot plant could also be leased in the future by other ethanol producers seeking a site to test various feedstocks. Scale-up plans won’t be determined until after trials have been run at the pilot scale and Kor said price will be a major factor in any possible future decision to switch feedstocks at Pinal’s Maricopa plant. “We’ll see how these trials go,” he said. “There are times when corn gets too expensive and we switch to milo, but it will really be price sensitive.”