A California ethanol plant and a dairy team up to build a methane digester
When officials from a nearby ethanol plant approached him last year about a methane digester project, dairy producer Frank Junio was skeptical.
"My first thought was, ‘Why would I want to get hooked up with them?’" recalls Junio, who milks 1,600 Jerseys at his family’s dairy near Pixley, Calif.
Calgren Renewable Fuels could cite a couple of good reasons. The plant wanted the biomethane from Junio’s dairy manure to help power its ethanol-making operation. Located less than a mile north of the Junios’ Four-J Dairy, Calgren proposed building an underground pipeline to transport raw manure to a digester it would construct on its ethanol-producing site. Would Four-J be interested in a new manure management infrastructure and dried solids for freestall bedding, at no cost?
Junio’s hesitation wasn’t so much that the ethanol industry had become something of a villain to livestock producers, who blame soaring feed prices on ethanol’s growing demand for corn. The issue was more pragmatic for the third-generation dairy producer. "A lot of ethanol plants were going out of business in the Midwest," Junio says. "It didn’t seem like the right thing for us to do."
But for Calgren and project manager Daryl Maas, the Pixley biogas project made total sense. "I wouldn’t be here if I didn’t think this would work," says Maas, whose Farm Power Northwest company owns five dairy digesters in Washington and Oregon.
"The biogas industry has been plagued by delusions of grandeur," acknowledges Maas. "But this is a good, practical project. It involves neighbors who are working together with knowledgeable people. They’re taking on a project of manageable size that provides a direct benefit for both the dairy and the ethanol plant."
Junio’s doubts eased after meeting with Maas and Calgren’s president, Lyle Schlyer. "Lyle assured us they are here for the long haul," he says.
The dairy producer now sees the project as "a big plus for us."
Calgren first fired up its ethanol plant in 2008. One of California’s three operational ethanol plants, it produces 58 million gallons of ethanol a year, as well as wet distillers’ grains and corn oil. Nearly all of the plant’s corn comes from the Midwest.
From the beginning, Calgren saw opportunity in powering its plant with biomethane, not just fossil-fuel based natural gas. The company wanted to reduce its pollutant emissions and meet new federal guidelines under the Renewable Fuels Standard. And it sat in Tulare County, one of the nation’s top dairy areas. "If we could substitute a waste product to power our plant, we would make a more environmentally friendly ethanol product," Schlyer says.
Calgren had another need. Because it generates its own electricity and steam, it produces hot stack gases and ends up with excess heat. That heat surplus could keep a methane digester at consistently high temperatures—perfect for the anaerobic process and producing methane. "We would improve efficiency and consume less fuel," Schyler says.
The company turned to Maas, who helped write a grant proposal for the digester-pipeline project. In April 2010, the California Energy Commission awarded Calgren a $4.68 million matching grant to pay for half of the project.
Calgren is still deep in the permitting process for the project, which operates under the name Pixley Biogas Company. It hopes to begin construction by early next spring. Under Maas’ direction, the company will install a GHD-modified, plug-flow digester system about 100 yards north of the ethanol plant, which sits beside busy Freeway 99. Schlyer hopes the biomethane will reduce the plant’s natural gas usage by 8%.
At Junio’s dairy, raw manure will no longer flow into a lagoon. Instead, it will enter an underground pipeline and head to the digester. Junio will receive a valuable digester byproduct: pathogen-free manure solids, known as biofibers, which he’ll use as bedding in his freestalls. Another benefit will be the digester’s liquid wastewater, returned to the Junios via pipeline. They’ll apply that to their 800 acres of crops.
Beyond those benefits, Junio sees expansion possibilities. "We need this new infrastructure to allow us to expand and build a new milk barn," he says. "Because it will be environmentally correct, we think it can help us get permitted to do that.
"If this all comes to fruition, it will mean $500,000 to $1 million in benefits for us," adds Junio, who’s signed a long-term contract with Calgren. "Nothing’s a sure thing. Technology could change, something could happen. But it’s all positive at this point."
Local Opposition Slows the Project
Calgren’s methane digester pipeline project with Frank Junio’s dairy is a scaled-down version of an earlier plan. Originally, Calgren wanted a bigger digester. The ethanol company planned to supplement the manure it received from the dairy with waste trucked in from dairies in a two-mile radius.
"It was the county planning staff’s position that the digester at that location would meet all relevant local codes and ordinances, and we recommended approval of the project," says Benjamin Kimball, chief planner for Tulare County.
But opposition from local residents, farms, businesses and the Pixley town council over perceived transportation and odor issues, as well as a sense that the public had not been adequately informed about the project, forced a change in plans.
"We’re not looking for a fight," says Calgren’s president, Lyle Schyler.
To appease those concerns, Calgren downsized the project to 60% of its original size. The revised plans include a smaller digester, supplied by the manure and liquid from Junio’s dairy alone. Kimball believes Tulare County’s Planning Commission and Board of Supervisors will eventually approve the project.
"The scaled-down project will be easier to achieve," says project manager Daryl Maas. "We’re eager to get it going."