The Intergovernmental Panel on Climate Change (IPCC) is clear: making a meaningful dent in global warming will require more than reducing greenhouse gas emissions. With that forewarning, some companies are hustling to find ways to go further: working to remove carbon dioxide (CO2) from the atmosphere and sequester it indefinitely.
Finish-based technology developer Carbo Culture is a startup making headway along that carbon removal and sequestration path. Its patented process, which it calls Carbolysis, converts CO2 from biomass into biochar for use in several applications. The process removes CO2 from the atmosphere and the biochar will either be sequestered securely underground or sequestered within the product itself, depending on the product.
Now nearing the last stretch of its R&D work at a California pilot test site, the team’s plan is to launch a commercial site in Europe, slated for 2024, then to eventually go global. Target markets are carbon credits, syngas utilization, and agricultural applications for biochar.
“Our primary objective is carbon removal, which we accomplish by creating the biochar,” says Charlotta Liukas, head of Operations, Carbo Culture.
She explains: “We take waste biomass and most of that is inherently carbon from plants that store the carbon in soil. But eventually the plants decay or get burned and most of the carbon is released into the atmosphere as CO2. When we convert that biomass to biochar the carbon stays stable and will not get released as CO2.”
Researchers at the University of Hawaii developed the conversion technology. Since its contractual agreement with the University to utilize it, Carbo Culture has scaled capacity by tenfold to a nameplate capacity of about 50 tons of biochar (150 tons CO2). The team aims to increase production capacity by fourfold by the end of 2022.
Work is in progress to prepare for commercial roll out of the technology, with a $2.2 million grant from the European Innovation Council (EIC). The EIC is the EU’s flagship accelerator.
One key to scaling is cranking out more applications.
“The more products you can output, the more you can lower your operational costs. For us that will require further validating to really nail down the concept, and from there to scale,” Liukas says.
But at the end of the day, she says, it’s really about the system that produces biochar.
“We can make more product quicker and sequester more CO2 by improving the efficiency of the reactor.”
The agriculture sector will be a primary market. The biochar can be mixed with nutrients that go in soil.
Because the process yields material with a high surface area and conductivity, it’s suitable for multiple applications, Liukas says. Among attributes it has high-water retention capacity to keep water in soil longer, and it can act like a slow-release fertilizer.
The biochar can also be used in applications that require filtering or absorption, for instance to limit nutrients leaching into soil or to prevent them from entering waterways. And it has been found effective in soil substrate material (a media in which specialty crops grow).
A material to make functional, carbon-negative concrete is also in the pipeline. That project is in development to make heatable concrete products, with support from a €600k grant (about $615,000) awarded by the German Federal Agency for Disruptive Innovation SPRIN-D.
At a basic level, the process to make the various commodities involves carbonizing biomass at a high temperature with a pressurized system to create a biocarbon of over 90% carbon. The biochar contains no toxins such as PAH (polycyclic aromatic hydrocarbons), which are generated whenever substances are burned and can be an issue with lower-grade biochar.
About 50% of the carbon is stabilized into biochar. The rest is released as mixed syngases, which will be used in energy applications.
“We envision the first European plant will make heat from syngas. Later we may separate and further purify the mixed syngases for other applications,” Liukas says.
The team is beginning to talk to offtake partners – energy companies that deliver central district heating for businesses and residential properties.
Puro.earth, a voluntary carbon credit marketplace, verified the pilot plant in California and Carbo Culture is selling carbon credits through the organization’s B2B platform.
Customer service software company Zendesk is among the first to sign a carbon credit purchase agreement with Carbo Culture.
“The carbon removal industry is still a long way away from scale,” Megan Trotter, vice president, Social Impact at Zendesk said in a statement. “At Zendesk, we are proud to help promising new technologies catch their stride. In Carbo Culture, we see a new approach to bringing biochar to the center stage of fighting climate change.”
The company has a pitch for waste stream generators; it wants more biomass suppliers looking to valorize their stream if their material is good for biochar production.
“We are interested in straw, hemp, or other residual side streams from agriculture, as well as from food production like discarded sugar beet pulp and other residues or discards of food manufacturers. Or from other industrial methods, like pulp or paper processes with residuals,” Liukas says.
Despite ambitious plans, Carbo Culture and the carbon removal industry at large have a way to go to crack global warming.
“Climate authorities say we will need gigatons of scale of carbon removal, and none of our solutions are there,” Liukas says.
Further, she admits, no one innovation will be the answer.
“We will need many methods and technologies. But with biochar technology it’s a near-market-ready solution. There is potential to scale and do this efficiently with nature’s help.”