Carbon-negative bioenergy technologies gain traction as a climate solution

Bioenergy with carbon capture and storage, BECCS, is gaining traction as a technological solution for reducing carbon emissions while adding to the global energy supply, but experts are arguing that it needs more clearly defined policy incentives to play a role in midcentury climate targets.

BECCS is among a suite of carbon dioxide removal technologies necessary to limit global warming to 1.5-2 degrees Celsius, yet it is one that has received less attention over the years relative to other CO2 removal solutions, such as direct air capture, afforestation, and biochar production.

But BECCS' allure is its carbon-negative component. Because the process uses organic waste materials before they are allowed to naturally decompose—a process that releases greenhouse gasses into the atmosphere—then adds CCS technology on the back end, the process has the net effect of reducing CO2 emissions while producing clean fuels.

According to a June 27 report from the Energy Futures Initiative, BECCS's status as a climate solution is gaining traction.

"As the only net-negative technology that can also provide energy and power, BECCS is seeing growing attention in recent years from policymakers and companies looking to meet net-zero emissions targets," said Richard Newell, CEO of Resources for the Future, a think tank that organized a presentation of EFI's new report. "But [the] deployment of BECCS at scale is not without its challenges."

In the Intergovernmental Panel on Climate Change's Sixth Assessment Report, released last year, carbon dioxide removal technologies will need to account for around 6 gigatons/year of CO2 globally by 2050, a total that is roughly equivalent to US annual emissions today. And the IPCC calls on BECCS to account for nearly half of that 6 gigaton/year total.

Ethanol production is the largest bioenergy activity in the US. For BECCS to scale to the levels the IPCC identified, the bioenergy industry will have to diversify beyond ethanol, to be used in products like biodiesel, renewable natural gas, and sustainable aviation fuel. Some producers have even launched projects producing biohydrogen—a process that converts biomass to biogas, then spits that biogas into hydrogen and carbon in an autothermal reformation process.

Scaling biomass feedstock

Scaling BECCS to these new levels will require an enormous amount of biomass feedstock, a category that includes everything from organic agricultural waste to municipal landfill waste and forest debris cleared during wildfire mitigation operations. According to EFI Executive Vice President Joseph Hezir, who led the group's report, the US should aim to produce around 500 million mt/year of biomass for BECCS development.

"There is a significant potential for a feedstock base that is managed in a sustainable manner from various residuals and other forms of biomass that currently have little or no market value," Hezir said.

There are two primary categories through which the US could reach that 500 million mt/year target—residues and wastes that currently have no market value, and biomass grown on land not suited for agricultural production or on agricultural lands set aside for conservation. "BECCS can use biomass that has little to no market value and create value in that process," Hezir said.

One of the more attractive sources for new biomass is projects coming from wildfire-management measures, wherein smaller trees or other woody plants on the lower levels of a forest are removed to prevent fires from spreading into the upper canopies.

"Currently we have the processing capacity and markets for large diameter timber, but much less so for smaller diameter trees and other kinds of woody biomass," said Senator Martin Heinrich, a New Mexico Democrat advocating for BECCS policy support. "BECCS systems could be that market. They could make profitable the removal of small-diameter woody fuels that are often destined to act as ladder fuels for wildfires. If we can integrate those systems into active forest management practices, BECCS systems could help us reduce the intensity of our wildfires, and ... our carbon emissions."

Further policy support

Even after the bevy of clean tech policy support packaged in the Inflation Reduction Act and the Bipartisan Infrastructure Act, BECCS does not have the same level of government support as other technologies.

Earlier this year, researchers at the Columbia Center on Global Energy Policy, cited similar concerns for carbon-negative technologies.

"I'm so thankful to the IRA for basing [subsidies] on carbon intensity, but the negativeness of the emissions is absent," Columbia researcher Anne-Sophie Corbeau said in March 2023. "You are not valued more if you are going into negative emissions. I think this is something that is missing in all the policy frameworks. There should be even more reward for something that is actually reducing your emissions."

The EFI report suggests that clear policy signals are needed to encourage BECCS deployment at scale. That support could piggyback off existing incentives within the Inflation Reduction Act and the Bipartisan Infrastructure Law, the report says, such as the 45Q tax credit program, which subsidizes carbon capture technologies. Or policymakers could expand existing incentives within the upcoming farm bill to incorporate biomass production.

"We know there are voices out there that would prefer other pathways towards deep decarbonization, but the reality is, in our view, we need all of the above, because the fight for every tenth of a degree is really important," said EFI CEO and former US Energy Secretary Ernest Moniz. "If we're going to a net-negative economy eventually, you can't do it without negative carbon technologies."