There is a substance that's easy to make that could reverse the trend of global warming, increase plant production, retain water and eliminate the need for chemical fertilizers. No, it isn't that magic extraterrestrial spice from Dune; it's something everyone can make in their own backyard. It can be scaled up for large projects. It can even be made as a byproduct of energy production. It's virtually unknown to most of the world. It's biochar.
"It seems too good to be true," says David Morell, former Environmental Protection Agency administrator and project manager of the Sonoma Biochar Project. "If it's as good as its proponents say, why isn't it used everywhere? And it feels like magic—we're sequestering carbon, capturing energy, helping plants grow, saving the planet, yadda, yadda. And that makes something hard to sell.
"I've actually run seminars on this," adds Morell. "'If it's such a good idea, why aren't we doing more of it?' The answer has to do with marketing."
Let's back up a step. First of all, what is biochar? It's basically charcoal made from biomass like plants and trees that have been pyrolized—that is, burned at very high temperatures (650–930 degrees) without fire. "The heat drives off all the gasses that are in the wood, leaving pure, elemental carbon behind," explains Morell. Carbon is retained much more efficiently through this process, and that sequestered carbon can be buried in the earth, where it retains about 80 percent of its carbon for at least a hundred years, according to Johannes Lehmann of Cornell University, one of the nation's leading biochar scientists.
Lehmann theorizes that 10 to 12 percent of the world's carbon emissions can be offset by replacing a slash-and-burn technique with slash-and-char, which would turn the waste plants into biochar through on-site pyrolisis units. So far, biochar has proven to be the most realistic—if not the only—carbon-negative energy production method we've ever known.
The idea of burying charred wood goes back to about 2,500 B.C.E., when indigenous peoples in the Amazon rainforest began making and burying primitive biochar to make the notoriously infertile soil better for growing crops. They didn't worry about carbon sequestration, however. Atmospheric carbon dioxide has increased from 280 ppm in 1750 to 367 ppm in 1999, according to data from Cornell University, and the levels of today have not been exceeded at any time in the past 420,000 years.
But the data on biochar's big four benefits—carbon sequestration, soil health, water conservation and energy production—only goes back about 15 or 20 years, says Morell. His work focuses largely on water retention, which he says has shown, in some cases, to be as high as 8 percent more than non-biochar soil.
The Sonoma Biochar Project kicked into gear with a $75,000 federal grant in October—which was matched by the Sonoma County Water Agency and by passionate experts like Morell and farms like Green String and Swallow Valley—to build the county's first integrated biochar production system. It makes about 500 pounds of biochar per day, enough to just about cover a quarter-acre. Even with this breakthrough—they designed and built the unit from scratch to ensure minimal air emissions—they're on "the low end" of biochar production. "It's like buying a car that you have to crank on the front," says Morell, adding that the top-tier units cost upwards of $250,000.
As for marketing, that's something Raymond Baltar has been working on as director of the Sonoma Biochar Initiative, the nonprofit arm of the Sonoma Ecology Center which oversees the Sonoma Biochar Project. "There is not a huge market right now for biochar," he says. "It's growing, but it's still pretty small compared to other soil amendments out there because it's so new."
For his MBA thesis at Dominican University, Baltar wrote a business plan for a gassification program at the Sonoma County landfill that also produced biochar. "We showed pretty conclusively that in order to make the project work you needed biochar and the electricity generation portion of it," he says.
"Initially, I think, biochar caught wide attention because of the potential for carbon sequestration," says Morell. "Putting carbon effectively into the ground is an attractive process. But the economics of that is near zero. In the U.S., we have no carbon credits. We have no ability to generate economic return from dealing with the planet's climate challenge. That's kinda crazy, but it's true."
One of the downsides raised about biochar is that if this is done at scale, people might start farming trees just to make biochar.
"But that might help carbon dioxide absorption anyway," Baltar says.—Nicolas Grizzle