Biomass-energy dreams

Thor Bailey has a problem. He says that the agricultural-biomass industry he had hoped to see become a big player among energy providers over the last 30 years seems stagnant. Generating carbon-neutral energy from agricultural biomass—such as the trimmings of orchards or rice hulls, which are often discarded or burned—seems so progressive, and yet in many ways, according to Bailey, the concept is stuck in the 1970s; many plants have failed to keep up with environmental regulations, while others were shut down because they weren’t financially viable. Infrastructure for new plants to be successful is largely unbuilt.

“We’re struggling with how we can take advantage of learning the hard way what didn’t work, and how can we, the industry, [move forward] over the next 30 years, based on what we learned in the last [30],” Bailey said. Thus, he and several colleagues got together to make sure what they’ve learned is passed on to younger North State small farmers interested in the technology via the Agricultural Biomass Center (ABC), the Colusa-based nonprofit he helped form in 2004. As ABC’s website puts it, the organization aims to provide “a forum of collaboration, education and insight to provide farmers, energy producers, and technology providers the ability to work together.” ABC is currently working with Orland’s T. M. Duché Nut Co. and Premier Mushrooms in Colusa on developing a plan to recycle their agricultural wastes.

In the case of orchards, Bailey said, larger producers have machinery to chip orchard trimmings into useful mulch on-site, but smaller farms—40 or fewer acres—often can’t afford to do much else than burn it or send it to the landfill. “[Small farmers are] probably burning 30 to 40 percent of the prunings, throughout the valley,” said Bailey. Primarily, those are small orchards that can’t afford to pay for it to be hauled away or buy chipping machinery. “There’s not enough volume to cover the cost to process it on-site.”

ABC’s vision is to help small farmers and energy producers collaborate, to turn those smaller-farm wastes into biogas—a usable gas emitted from the waste when processed—and soil amendments instead, by securing investor funding to build small processing facilities in strategic locations. ABC recognizes that “there isn’t a one-size-fits-all” in biomass processing. Envisioning future infrastructure has to take into account such things as the types of farms and waste inputs involved, how far the waste would need to be trucked to a facility, and which processing technology would be most viable. ABC is working on finding “innovative ways to help finance smaller projects from the private sector,” said Bailey.

Several Northern California facilities already collect farm waste to produce energy. Some are “in-house, closed-loop” systems, said Bailey. A methane digester at Marin County’s Straus Family Creamery captures the methane from cows’ manure to use as energy. In Winters, organic-walnut producer Dixon Ridge Farms uses its walnut shells in a process called gasification, in which the material is burned at high temperatures with a controlled amount of oxygen.

A similar method of processing waste through burning called pyrolysis, which uses very low levels of oxygen, however, is the method preferred by ABC, said Bailey. Its byproduct, biochar—charcoal made by the process of pyrolysis—is gaining popularity as a soil amendment. Because of its high carbon content, environmentalists advocate its use for carbon sequestration; when biochar is made and then buried, much of the carbon that would otherwise be burned and sent into the atmosphere as carbon dioxide is instead trapped in the biochar, according to the U.S. Biochar Initiative (go to www.biochar-us.org to learn more). Additionally, it is praised for its ability to filter water, meaning cleaner aquifers.

“There’s a bigger market [for biochar] than there is product available,” noted Bailey.

The list of benefits from agricultural-biomass energy generation is long: It keeps agricultural wastes out of the landfill and lessens agricultural burning, provides an alternative fuel source, decentralizes energy production, creates local jobs and produces a marketable product for soil fertility.

“Soil health—soil tilth—is the primary driver for ABC, and renewable energy is secondary,” said Bailey. And yet, while a few companies have their own biomass facilities, smaller-scale projects aren’t profitable, due to competing costs of other energy sources like natural gas, “stringent, burdensome environmental regulations,” and a lack of infrastructure, he said.

“The reality is, if you scale down, the returns aren’t there,” explained Bailey. Larger, collaborative projects have enough input to justify the large initial investment for the processing plant.

Clean World Partners (CWP), a young Sacramento for-profit business specializing in small-scale anaerobic digesters, says the opposite—that scaling down is profitable. Anaerobic digestion of biomass is in essence a composter without oxygen, which, like the thermal technologies, produces biogas and a compost-like byproduct.

“We have the same challenges,” like lack of infrastructure and the lack of startup money to build facilities, that Bailey mentioned, “but we think we’ve overcome them by scaling down,” said Warren Smith, CWP’s vice president of business development.

CWP debuted its first anaerobic digester last month in Natomas, which it claims will turn a profit. CWP’s proprietary anaerobic-digester technology, based on research done at UC Davis, is the better technology, said Smith. “We have no interest in thermal technologies,” like pyrolysis, Smith said.

Smith believes the landscape of interest has changed. Just 10 years ago, the motivation to build facilities was “government-directed” with a “public-sector push,” he said.

However, “in the last couple of years, we’ve seen private-sector pull,” as a result of companies motivated to find a sustainable solution for their waste stream, and to show off to their investors and customers, who are asking for green change.

“We’re starting to see projects that are penciling,” explained Smith. CWP’s partners are not strictly agricultural—its new facility in Natomas, for example, digests corrugated cardboard along with other wastes.

For his part, Bailey will continue to work on ABC’s version of the biomass future.

“It’s not about us anymore—it’s about our kids and grandkids,” he said.