What is in this article?:
- Former San Joaquin Valley sugar beet growers are expected to learn next month if funding will be forthcoming for a pilot biorefinery near Mendota, Calif.
- If the pilot plant proves feasible — next step would be an ambitious plan to build biorefinery that produces 36 million gallons of ethanol annually: plus 6.3 megawatts of certified green electricity, 1.6 million cubic feet of renewable biomethane, and high-nutrient non-synthetic compost and liquid fertilizer.
Rusty Gragnani, left, vice president of the Mendota Advanced Bioenergy Beet Cooperative board, stands next to a map showing the area to be served by the beet cooperative. Bill Pucheu, Cooperative board president, holds a schematic of the plant’s many components.
Wood byproduct fuel
Jim Tischer of the California Water Institute at California State University, Fresno serves as project coordinator.
Working with energy crop experts from the University of California, Davis and bioenergy specialists in the U.S., Germany and Switzerland, the group determined a pilot plant was feasible and applied to the California Energy Commission to build it.
The idea of utilizing beets for biofuel is not new, but the approach taken by the Mendota energy cartel is.
One of the biggest drawbacks in getting ethanol from beets is the energy cost. The Mendota biorefinery process will generate as much as 50 percent of its energy from wood byproducts.
“There are 100,000 acres of almonds alone within 30 miles of the plant site,” said Diener. These woody byproducts, an estimated 80,000 tons of almond prunings and other agricultural waste, would be fed into a biomass gassifer cogeneration plant to generate power and heat.
Along with the ethanol, Mendota Bioenergy expects to produce 6.3 megawatts of certified green electricity, 1.6 million cubic feet of renewable biomethane, and high-nutrient non-synthetic compost and liquid fertilizer.
With fresh water for irrigating, and city dwellers growing more scarce in the valley, the Mendota project will get its water from urban and ag wastewater.
The plant’s green biogas would be sold into the commercial utility market. The natural gas would fuel trucks and pumps. Waste water from the plant will be used on farms and in parks and landscaping. The fertilizer production component would be 10-10-10 fertilizer from anaerobic digesters.
The plant also will produce biodiesel from high-yield, salt-tolerant canola.
The goal is to build a biorefinery that will utilize between 840,000 to 1 million-plus tons of sugar beets annually within a 60-mile radius of the plant each year.
The beet feedstock for the plant are called energy beets, not sugar beets. “You have to forget about the sugar like we did when we grew beets for the sugar market,” said farmer Rusty Gragnani. Energy beets are larger and are likely to produce 50 to 60 tons per acre versus the more typical 40 tons when beets are produced for sugar only.
Diener said part of the yield increase would come from growers not being asked to trim the beets before delivering them as they did for sugar production. He said the bioenergy plant will use everything delivered from the field.
Cellulosic energy beets will produce up to 1,200 gallons of ethanol per acre compared to approximately 450 gallons per acre from corn-based ethanol. Biorefineries in Germany and France have been producing ethanol from energy beets for several years. There are at least three other locations in the U.S. where farmers and others are looking to do what the Central Valley group is attempting.
Bill Pucheu , Tranquillity, Calif., farmer and cooperative board chairman, said growers would earn $40 to $60 per ton for the beets delivered to the full scale plant that, under the current time table, would be operational in June 2016.