The fight against climate change is complex, demanding innovative and sometimes controversial solutions. In the urgent race to achieve “negative emissions,” Big Tech is making a significant investment in a carbon removal strategy that promises to pull vast amounts of greenhouse gases from the atmosphere, but not without drawing scrutiny from environmental experts. This strategy is known as bioenergy with carbon capture and storage, or BECCS, and it’s rapidly gaining traction among the world’s largest corporations.
Big Tech’s Big Bet: The Allure of BECCS
Over the last century, much of the US pulp and paper industry crowded into the southeastern corner of the nation, setting up mills amid sprawling timber forests to strip the fibers from juvenile loblolly, long leaf, and slash pine trees. Today, after the factories chip the softwood and digest it into pulp, the leftover lignin, spent chemicals, and remaining organic matter form a dark, syrupy by-product known as black liquor. It’s then concentrated into a biofuel and burned, which heats the towering boilers that power the facility—and releases carbon dioxide into the air.
Microsoft, JP MorganChase, and a tech company consortium that includes Alphabet, Meta, Shopify, and Stripe have all recently struck multimillion-dollar deals to pay paper mill owners to capture at least hundreds of thousands of tons of this greenhouse gas by installing carbon scrubbing equipment in their facilities. The captured carbon dioxide will then be piped down into saline aquifers more than a mile underground, where it should be sequestered permanently.
Big Tech is suddenly betting big on this form of carbon removal, known as bioenergy with carbon capture and storage, or BECCS. The sector also includes biomass-fueled power plants, waste incinerators, and biofuel refineries that add carbon capturing equipment to their facilities. Since trees and other plants absorb carbon dioxide through photosynthesis and these factories will trap emissions that would have gone into the air, together they can theoretically remove more greenhouse gas from the atmosphere than was released, achieving what’s known as “negative emissions.”
The companies that pay for this removal can apply that reduction in carbon dioxide to cancel out a share of their own corporate pollution. BECCS now accounts for nearly 70% of the announced contracts in carbon removal, a popularity due largely to the fact that it can be tacked onto industrial facilities already operating on large scales.
“If we’re balancing cost, time to market, and ultimate scale potential, BECCS offers a really attractive value proposition across all three of those,” says Brian Marrs, senior director of energy and carbon removal at Microsoft, which has become by far the largest buyer of carbon removal credits as it races to balance out its ongoing emissions by the end of the decade.
This surge in interest is partly due to grave climate warnings. In addition to dramatic cuts in emissions, the world may need to suck down 11 billion tons of carbon dioxide per year by 2050 and 20 billion by 2100 to limit warming to 2 °C over preindustrial levels, according to a 2022 UN climate panel report. For companies with fast-approaching climate deadlines, BECCS is one of the few options for removing hundreds of thousands of tons over the next few years.
“If you have a target you want to meet in 2030 and you want durable carbon removal, that’s the thing you can buy,” says Robert Höglund, who cofounded CDR.fyi, a public-benefit corporation that analyzes the carbon removal sector. He notes that these projects can harness the infrastructure of existing industries, making them relatively quick to implement. BECCS is also substantially less expensive for buyers than, say, direct air capture, with weighted average prices of $210 a ton compared with $490 among the deals to date, according to CDR.fyi.
Microsoft, for example, announced plans in 2020 to become carbon negative by the end of this decade. It’s leaning particularly heavily on BECCS, with the category accounting for 76% of its known carbon removal purchases to date. This includes massive deals, such as purchasing 3.7 million tons of carbon dioxide from a southern US paper and pulp mill through CO280, and an even larger agreement for 6.75 million tons of carbon removal from AtmosClear, which is building a biomass power plant in Louisiana.
The Controversial Side of Carbon Removal: Decoding BECCS
Despite its appeal, experts have raised a number of concerns about various approaches to BECCS, stressing they may inflate the climate benefits of the projects, conflate prevented emissions with carbon removal, and extend the life of facilities that pollute in other ways. It could also create greater financial incentives to log forests or convert them to agricultural land.
When greenhouse-gas sources and sinks are properly tallied across all the fields, forests, and factories involved, it’s highly difficult to achieve negative emissions with many approaches to BECCS, says Tim Searchinger, a senior research scholar at Princeton University. That undermines the logic of dedicating more of the world’s limited land, crops, and woods to such projects, he argues. “I call it a ‘BECCS and switch,’” he says, adding later: “It’s folly at some level.”
The logic of BECCS works like this for a biomass-fueled power plant: A tree captures carbon dioxide from the atmosphere as it grows. Someone then cuts it down, converts it into wood pellets, and delivers it to a power plant that burns the wood. Under EU and US rules, burning wood is generally treated as carbon neutral, assuming sustainable forest management. If that same power plant then captures a significant share of the greenhouse gas produced and pumps it underground, the process can potentially go from carbon neutral to carbon negative.
However, the starting assumption that biomass is carbon neutral is fundamentally flawed, because it doesn’t fully take into account other ways that emissions are released throughout the process, according to Searchinger. A proper analysis must also ask: How much carbon is left behind in roots or branches on the forest floor that will begin to decompose and release greenhouse gases after the plant is removed? How much fossil fuel was burned in the process of cutting, collecting, and distributing the biomass? How much greenhouse gas was produced while converting timber into wood pellets and shipping them elsewhere? And how long will it take to grow back the trees or plants that would have otherwise continued capturing and storing carbon?
“If you’re harvesting wood, it’s essentially impossible to get negative emissions,” Searchinger says. Moreover, burning biomass can also produce other forms of pollution that can harm human health, including particulate matter, volatile organic compounds, sulfur dioxide, and carbon monoxide. Emily Grubert, an associate professor of sustainable energy policy at the University of Notre Dame, notes that while preventing CO2 emissions might capture some other pollutants, it doesn’t necessarily filter out all the other pollution floating out of the flue stack.
The critical question with using waste biomass, a seemingly ideal feedstock for BECCS, is whether it would otherwise have been burned or allowed to decompose, or might some of it have been used in some other way that kept the carbon out of the atmosphere? Sugarcane bagasse, for instance, is or could also be used to produce recyclable packaging and paper, biodegradable food packaging and cutlery, building materials, or soil amendments. “A lot of the time those materials are being used for something else already, so the accounting gets wonky really quickly,” Grubert says. Some fear that the financial incentives to pursue BECCS could also compel companies to trim away more trees and plants than is truly necessary, creating perverse incentives to produce waste, as Danny Cullenward, a researcher at the University of Pennsylvania, points out.
Navigating the Nuances: Waste, Due Diligence, and Future Standards
Notably, many BECCS projects, including several supported by Microsoft, rely on some form of waste, a category distinct from fresh-cut timber or crops grown for the purpose of fueling BECCS projects. Solid waste, agricultural residues, logging leftovers, and plant material removed from forests to prevent fires present some of the ripest opportunities for BECCS. A 2019 report from the National Academy of Sciences estimated that the US could achieve more than 500 million tons of carbon removal a year through BECCS by 2040, while the world could exceed 3.5 billion tons, by relying just on agricultural by-products, logging residues, and organic waste—without needing to grow crops dedicated to energy.
Roger Aines, chief scientist of the energy program at Lawrence Livermore National Laboratory, argues we should at least be putting these sources to use rather than burning them or leaving them to decompose in fields. He stresses that the BECCS sector can learn a lot from using that waste material. “The point is you won’t grow new material to do this in most cases, and won’t have to for a very long time, because there’s so much waste available,” Aines says.
Like other big tech companies, Microsoft has lost some momentum when it comes to its climate goals, in large part because of the surging energy demands of its AI data centers. But the company has generally earned a reputation for striving to clean up its direct emissions where possible and for seeking out high-quality approaches to carbon removal. Marrs says the company has extended that scrutiny to its BECCS deals. “We want as much positive environmental impact as possible from every project,” he says.
“We’re doing months and months of technical due diligence with teams that visit the site, that interview stakeholders, that produce a report for us that we go through in depth with a third-party engineering provider or technical perspective provider,” Marrs adds. In a follow-up statement, Microsoft stressed that it strives to validate that every BECCS project it supports will achieve negative emissions, whatever the fuel source. “Across all of these projects, we conducted substantial due diligence to ensure that BECCS feedstocks would otherwise return carbon to the atmosphere in a few years,” the company said.
Likewise, Jonathan Rhone, the cofounder and chief executive of CO280, stresses that they’ve worked with consultants, carbon market registries, and pulp and paper mills “to make sure we’re adopting the best standards.” He says they strive to conservatively assess the release and uptake of greenhouse gases across the supply chain of the mills they work with, taking into account the type of biomass used, growth rate of forests, shipping distances, total facility emissions, and more. Proponents of BECCS say we could leverage biomass to deliver substantial volumes of carbon removal, so long as appropriate industry standards are put in place to prevent, or at least minimize, bad behavior. The question is whether that will be the case—or whether, as the BECCS sector matures, it will veer closer to the pattern of carbon offset markets, which have often been criticized for exaggerated climate benefits.
Conclusion: Beyond the Magic: A Call for Accountability in Carbon Removal
Even with all these carbon accounting complexities, BECCS projects can often deliver climate benefits, particularly for existing plants. Adding carbon capture to an operating paper and pulp mill, power plant, or refinery is at least an improvement over the status quo from a climate perspective, insofar as it prevents emissions that would otherwise have continued. However, ambitions for BECCS are already growing beyond existing plants, raising critical questions about the true climate impact of new facilities.
If biomass isn’t carbon neutral, as Searchinger and others argue it can’t be in many applications, then new unfiltered biomass power plants are just adding more emissions to the atmosphere—and BECCS projects aren’t drawing any out of the air. This raises tough questions about corporate climate claims and the societal trade-offs involved, such as land use for energy crops versus food production, or increased pressure on forests already vital for carbon sequestration and biodiversity. Searchinger argues that we’re better off adding carbon capture and storage (CCS) equipment to an existing natural-gas plant instead, as it’s more efficient and avoids pressure on natural resources. “People think some magic happens—this magic combination of using biomass and CCS creates something bigger than its parts,” Searchinger says. “But it’s not magic; it’s simply the sum of the two.”
The path forward for carbon removal, particularly with BECCS, demands rigorous oversight, transparent accounting, and a commitment to verifiable negative emissions, not merely prevented ones. As Big Tech pours billions into these ventures, the success of their climate commitments—and our planet’s future—hinges on ensuring these solutions deliver real, lasting environmental benefits, free from inflated claims or unintended consequences.
