Lawrence Livermore National Laboratory (LLNL) scientists have identified a suite of technologies to help California to become carbon-neutral—and ultimately carbon-negative —by 2045. To achieve the goal of carbon-neutrality, California will likely have to remove on the order of 125 million tons per year of CO₂ from the atmosphere.

In the report, “Getting to Neutral: Options for Negative Carbon Emissions in California,” funded by the Livermore Lab Foundation (LLF) with grant support from the ClimateWorks Foundation, LLNL focused on three specific pillars of negative emissions: natural and working lands; carbon capture from biomass conversion to fuels; and direct air capture.

The three main pathways to negative emissions (removing CO₂ from the atmosphere) for California are restoring natural ecosystems, converting waste biomass to fuels while capturing the CO₂ generating during processing, and direct air capture machines. Source: “Getting to Neutral”

The team identified a portfolio of approaches for achieving greater than 125 million metric tons per year of negative emissions for California by 2045 and evaluated the scope of state and private investment to best achieve the goal.

Of the three, the authors concluded that converting the state’s waste biomass (about 56 million bone dry tons per year) into fuels with simultaneous capture of the process CO₂ emissions holds the greatest potential for negative emissions in the State—some 84 million metric tons per year. More specifically, gasifying biomass to make hydrogen fuel and CO₂ has the largest promise for CO₂ removal at the lowest cost and aligns with the state’s goals on renewable hydrogen.

This study intentionally avoids any discussion of policies and does not include current incentives; it provides a range of options, tradeoffs and costs that can be used to inform future policies. The key finding of this report is that carbon neutrality is achievable.

—“Getting to Neutral”

The study was conducted as part of LLNL’s energy programs work and the Laboratory’s Carbon Initiative. The goal of the initiative is to identify solutions to enable global-scale CO₂ removal from the atmosphere and hit global temperature targets.

The report assesses the advanced carbon reduction technologies now available, their costs, as well as the tradeoffs necessary to reach the state’s decarbonization goal. The report codifies a number of significant conclusions by researchers at eight institutions. It serves as a resource for policymakers, government, academia and industry.

California can achieve this level of negative emissions at modest cost, using resources and jobs within the State, and with technology that is already demonstrated or mature. This is our conclusion after a comprehensive, first-of-its-kind, quantitative analysis of natural carbon removal strategies, negative emissions technologies, and biomass and geologic resources in the State, using methods that are transparently detailed in this report. We also find that realizing this goal will require concerted efforts to implement underground carbon storage at scale, build new CO₂ pipelines, expand collection and processing of waste biomass, and accelerate learning on important technologies, like direct air capture.

—“Getting to Neutral”

Background. California executive order B-55-18 mandates that the state achieve carbon neutrality by 2045 and maintain net negative emissions thereafter. Carbon neutrality refers to achieving net-zero carbon dioxide emissions by balancing any remaining atmospheric emissions with removal of carbon dioxide from the air, or simply by eliminating carbon emissions altogether. It applies to everything that generates greenhouse gases.

Achieving this goal would complete a chain of other ambitious statewide targets for reducing greenhouse gas emissions. The LLNL study finds that not only is carbon neutrality possible, but that California can be a global climate leader by demonstrating how to remove significant amounts of CO₂ from the atmosphere.

Without CO₂ removal, reaching our carbon neutrality goal will be slower, more difficult and costly. While there are no silver bullets, we have evaluated strategies that rely on many existing technologies and resources, creating a CO₂ removal blueprint that can be replicated.

—LLNL chemist Sarah Baker, lead author of the report