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U.S. firm buries oil made from farm waste, in costly carbon tech

by Alister Doyle | @alisterdoyle | Thomson Reuters Foundation
Wednesday, 10 November 2021 15:00 GMT

A sample of a glue-like oil produced from crop waste that is buried by U.S. Charm Industrial as a tiny step to slow climate change HANDOUT/Charm Industrial

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In a symbolic reversal of the fossil fuel era, a U.S. start-up is making and burying 'bio-oil' from crop waste, aiming to cut carbon emissions - but the method is still small-scale and expensive

By Alister Doyle

GLASGOW, Nov 10 (Thomson Reuters Foundation) - A U.S. company is burying a dark, gooey oil made from crop waste deep underground to fight climate change, using an expensive technology that marks a symbolic reversal of the fossil-fuel age.

Since starting operations in January, Charm Industrial says it has buried the equivalent of 5,000 tonnes of carbon dioxide contained in a "bio-oil" generated from agricultural waste such as crop stalks or walnut shells.

Charm's technology, from harvest to injection in rocks deep underground, costs an expensive $600 per tonne of carbon dioxide - and 5,000 tonnes is roughly the equivalent of the annual greenhouse gas emissions of just 300 Americans.

"It's still a drop in the bucket," but what will matter is the speed of boosting volumes, Charm's chief executive Peter Reinhardt told the Thomson Reuters Foundation on the sidelines of the COP 26 U.N. climate conference in Glasgow.

San Francisco-based Charm, with its 16 employees, represents a miniscule about-turn for the modern U.S. oil industry, which drilled its first commercial well in Pennsylvania in 1859.

Reinhardt says his long-term goal is to get prices down to $50 a tonne, adding that 5,000 tonnes exceeds the amounts buried so far by other carbon removal firms seeking to complement government efforts to cut emissions.

Switzerland's Climeworks, for instance, opened a facility in Iceland in September with capacity to suck 4,000 tonnes of carbon dioxide from thin air every year.

A "pyrolyzer", a machine used by U.S. firm Charm Industrial to convert crop waste into oil that it injects deep underground as a step to fight climate change. HANDOUT/Charm Industrial

Many environmental activists are dismissive, fearing sci-fi ideas distract from the emissions reductions that are meant to be the focus of the two-week COP26 in Glasgow. They point out that forests soak up carbon for free.

"Reduce emissions - stop talking about how you are going to capture them," said Juan Pablo Osornio, senior political lead for Greenpeace International.

"We need to carefully assess these technologies," said Diana Ürge-Vorsatz, a professor at the Central European University in Hungary.

They are costly, may require large amounts of energy and could have knock-on impacts for land use, forests, water, fertilisers and biodiversity, she added, noting that this was her personal opinion.

Ürge-Vorsatz separately co-chairs a U.N. panel of climate scientists looking at ways to solve global warming, with a report due for publication in 2022.

Still, she said the world will likely need to extract carbon from the air using nature to help get on track to avert worsening floods, heatwaves, droughts and loss of species this century.

Peter Reinhardt, chief executive of U.S. carbon removal firm Charm Industrial, looks at the venue for the COP26 U.N. climate negotiations in Glasgow, Scotland. November 8, 2021 Thomson Reuters Foundation/Alister Doyle


Charm has backers including Microsoft, Stripe and Shopify, which invest in carbon start-ups to offset their greenhouse gas emissions, hoping some will grow fast and be able to sequester huge volumes in future.

Nan Ransohoff, head of climate at digital payments processor Stripe, said the firm had so far committed $9 million to carbon removal tech firms, including Climeworks and Charm, at prices of up to $2,000 a tonne of carbon dioxide. The goal was to boost innovation, she added.

Reinhardt said waste such as stubble, corn husks, leaves and branches left over from timber harvesting could be turned into bio-oil and then buried. Such products are often used for animal feed, burnt or ploughed into the ground as fertilisers.

In Charm's process, the oil is produced in a "pyrolizer", a machine where biomass is heated, producing an oil low in energy and high in carbon in a self-sustaining chemical reaction. Reinhardt described the resulting oil as "carbon glue".

So far, the company has delivered crop waste to other firms that produce the oil in pyrolizers but is now building its own mobile model, able to fit on a truck.

It will travel to "wherever the cheapest biomass is", such as after harvest in Kansas or to Canada when foresters thin out woods, he said.

"Eventually we will operate the pyrolizer on the field, like a combine harvester. It will go back and forth, stop at the edge (and) unload a bunch of bio-oil," he said.

The hope, he added, is that thousands of farmers around the globe will adopt the technology.

(Reporting by Alister Doyle; editing by Megan Rowling @meganrowling. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers the lives of people around the world who struggle to live freely or fairly. Visit http://news.trust.org/climate)

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