Diego Saez-Gil moved from New York City to the old-growth forests of the Santa Cruz Mountains to learn what nature had to teach him. He planned to start a technology company that would use artificial intelligence to harness the carbon-sucking power of trees.
Then, last August, nature brought his house to ashen rubble in the CZU Complex Fire.
“I wanted to be close to the forest that I wanted to help protect,” he said. “In a very ironic turn of events, now I am a victim of climate change.”
But the immense loss only sharpened his focus on the urgency of the climate crisis. “I took it as a catalyst, as a reminder that this is something that’s happening right now, not in the future,” he said.
Saez-Gil’s company, Pachama, uses satellites, distance-measuring lasers and machine learning to calculate the carbon-capturing potential of nearly 40 forests worldwide, selling those savings as carbon credits to customers looking to offset their emissions.
Pachama is just one of a growing number of Bay Area startups turning their attention towards carbon drawdown—a process of trapping carbon dioxide before it’s released into the atmosphere. The technology has long been used to capture carbon directly from sources like oil refineries or chemical plants. But now, carbon dioxide levels are higher than at any point in at least the past 800,000 years, necessitating the need to remove already-existing carbon from the atmosphere, for good.
From data-driven reforestation to carbon-sucking rocks and even bio-oil extracted from plant waste, tech companies are starting to develop and deploy carbon removal solutions that they claim will help the world meet its emissions targets and avoid environmental collapse.
“We have polluted so much, especially with carbon,” said environmental scientist Lorenzo Rosa. “We need to do something big to mitigate our emissions.”
The downside to drawdown
The idea of capturing carbon from industrial processes like gas power plants was introduced in the late 1970s, according to the International Energy Agency. But recently, carbon capture and storage technologies have gained increasing attention from investors and policymakers alike.
Earlier this month in Iceland, a Direct Air Capture plant called Orca from the Swiss start-up, Climeworks, switched on its whirring fans to permanently trap and filter carbon underground.
In the United States, the Biden Administration has included carbon capture as part of its plan to reach 100 percent carbon pollution-free electricity by 2035. It has allocated billions of dollars in the Infrastructure Bill toward carbon capture and storage technology.
But some environmental groups argue that such technology, traditionally placed at refineries or coal plants to trap direct emissions from industry, perpetuates humanity’s dependence on fossil fuels.
“All of these so-called solutions are being put forth so that the fossil fuel industry can keep doing what it does,” said Joe Uehlein, president of the nonprofit Labor Network for Sustainability. Uehlein also pointed to the enormous energy and land use demands required to operate carbon capture processes.
Others, like Jim Walsh, a senior analyst at Food and Water Watch, are critical of the astronomical expense of such projects and said that even the most recent iterations of these technologies fall short.
Take the Orca project, for example. Walsh said, “They’re spending literally billions of dollars to capture a very small amount of CO2 relatively — the estimate’s around 800 automobiles being taken off the road — it’s a very expensive proposition.”
Still, scientists like Rosa are agnostic about how to reduce the volume of emissions spewed into the atmosphere. He only insists that we act, and soon. “The key is to decarbonize as quick as possible,” he said.
Analysis by the National Academy of Sciences and the Intergovernmental Panel on Climate Change shows that carbon removal technologies are critical to achieving U.S. and global emissions reduction targets by 2050, and a growing number of Bay Area start-ups bet they can play a crucial part in this transition.
Heirloom, for example, has bold plans to remove 1 billion tons of carbon from the atmosphere by 2035 through a process called carbon mineralization. Put simply, said Max Scholten, the company’s head of commercialization, Heirloom uses carbon-thirsty minerals like a sponge to draw down carbon and then wrings that captured carbon out underground.
Heirloom is essentially speeding up a naturally occurring geologic process with engineering and a high-temperature reactor, resulting in what the company claims is a safe, inexpensive process with huge potential.
“What we are doing is removing CO2, not avoiding emissions,” said Scholten, distancing the company from CCS and the fossil fuel industry. “We are taking CO2 that is already in the atmosphere out of the atmosphere.”
Charm Industrial is another such example. Started in San Francisco by founders Kelly Hering, Shaun Meehan and Peter Reinhardt, the company collects agricultural refuse, like corn or wheat stalks left over in fields after harvest. It then puts this plant waste, which sequestered carbon throughout its growth cycle, through a process called pyrolysis — basically, exposing the plant matter to high heat and forcing it to decompose in the absence of oxygen.
“Plants are the real heroes in this story,” said Hering, co-founder of Charm Industrial. “They are capturing the carbon, and they’re doing so in a very efficient way. They are not requiring electricity, any sort of power to do that.”
The engineering process produces three main byproducts: a carbon solid, called biochar, a gas, and vapor which the company then turns into a bio-oil. Charm then injects this oil into underground wells as negative emissions, “to put oil back where it came from, effectively,” said Hering.
Last year, the e-commerce giant Shopify supported the removal of 1,000 tons of carbon using Charm, and the company plans to sequester 3,000 additional tons by the end of 2023.
An uncertain future
These companies face a number of mounting challenges, including where to store the byproducts of their removal processes equitably and how to scale these nascent businesses affordably.
Both Heirloom and Charm are focused on underground storage, either in wells or aquifers, which the companies say are well understood by scientists. “They’ve been surveyed by the U.S. Geological Survey, by the EPA, by the federal government over the last 50 years or so. They’re very, very good stores of CO2 — and it’s permanent,” said Scholten of the salty underground aquifers.
Yet others are wary of underground transportation and storage, especially when it comes to carbon captured from industrial operations, which would require pipelines and deep wells. “All the pipes that we’ve ever put in the ground have leaked,” said Uehlein.
Both Heirloom and Charm say that environmental justice is top of mind as they scale their businesses and make decarbonization technology more affordable.
“We are not going to just plop down in someone’s backyard and build something that’s not wanted,” said Scholten, adding that there’s been some hesitation, especially concerning water contamination and seismic activity in an earthquake-prone state like California.
And even when storage is not a concern, nature-based solutions like Pachama’s also face risks. Increasing wildfires in the West and illegal deforestation in South America threaten global forests and can reverse any carbon savings gained through preservation or reforestation.
Rosa also points out that while projects like Pachama’s are critical, they will not alone meet global emissions targets. “We need to remember that carbon stored in trees is not a long-term carbon sequestration solution and we need to permanently remove carbon from the atmosphere,” he said.
It’s a sentiment that most everyone in this space seems to agree on. “We don’t need to have one technology that works,” said Scholten. “We need to have 10 technologies that work. We basically need as many shots on goal as possible in carbon removal.”