Through CDR (Carbon Dioxide Removal), we want to reduce atmospheric pollution; to do so, we need to know the capture capacity, operation costs, and risks. In the tenth chapter of “The State of Carbon Dioxide Removal, 3rd Edition” report, we find an analysis of how much different capture methods could remove and at what approximate costs, showing that wide ranges of uncertainty exist, alongside a set of methods with significant potential to contribute to climate goals, each with very distinct profiles of cost, capacity, and risks.
The intention is not to fix definitive figures but to organize available information in terms of cost ranges per tonne removed and sustainable annual potentials, explaining why these figures vary so much according to assumptions on storage durability, sustainability limits in land, water, or energy, value chain designs, and the geographic context in which CDR is deployed.
Cost Ranges and Potentials
The chapter highlights from the beginning that estimated costs for CDR span a very wide spectrum, from less than 10 dollars per tonne to more than 1,000 dollars per tonne of removed, and that for most methods, the upper cost limits exceed 200 dollars per tonne—meaning they are above the carbon prices observed in most current markets. Similarly, estimated potentials show dispersion: for several methods, the most reliable lower ranges sit around 1 per year or less, while upper ranges extend to several gigatonnes, though these high values usually depend on optimistic assumptions regarding resource availability and social acceptance. The discussed sources of uncertainty include the low technological and commercial maturity of some novel methods, the diversity of deployment scenarios considered in literature, the lack of consensus regarding minimum durability requirements, and heterogeneity in accounting for co-benefits and adverse effects.
Conventional Methods: Low Costs and Sustainability Limits
Regarding land-based conventional methods, such as afforestation and reforestation, forest management, carbon sequestration in agricultural and pasture soils, or wetland and peatland restoration, the report concludes that their costs per tonne tend to fall within the low and medium end of the spectrum, often in the tens of dollars per tonne, especially when capitalizing on synergies with other objectives like ecological restoration, productivity improvement, or erosion reduction. These methods can offer significant potential in the short and medium term, particularly if land-use practices are reformed and emissions linked to deforestation and degradation are decreased. However, the chapter insists that their expansion is limited by land availability and competition with other uses, such as food production, biodiversity conservation, and human settlement needs, and it underscores the vulnerability of these stores to reversibility—since forest fires, pests, or policy changes can release part of the stored carbon back into the atmosphere.
For all these reasons, although conventional CDR is essential today and relatively cheap in many contexts, the chapter warns that it cannot be assumed it can scale indefinitely without conflicting with other sustainability goals. When discussing the potential of these methods, it proposes clearly distinguishing between theoretical technical potential, which is usually very high, and sustainable potential, which incorporates constraints on land use, biodiversity conservation, and respect for the rights and livelihoods of local communities.
Novel Methods: High Costs, Durability, and Resource Requirements
In the case of novel CDR methods—such as bioenergy with carbon capture and storage, direct air capture of with geological storage, enhanced weathering, biochar applied to soils, mineral products that store carbon durably, or biomass burial—cost ranges are generally higher, and uncertainties are greater. The chapter shows that in most studies, BECCS and DACCS currently sit in cost bands of several hundred dollars per tonne, although some analyses anticipate significant reductions if deployed at a large scale, activating learning effects and economies of scale. Enhanced weathering and mineral products present costs that are highly sensitive to factors such as the distance between mines and application sites, the type of rock used, or the energy mix employed, producing ranges that can overlap with BECCS or DACCS, while biochar usually appears with slightly lower costs and relevant co-benefit profiles in agriculture, but also with limitations in sustainable biomass availability.
Storage Durability and Associated Risks
The report places emphasis on the fact that many of these novel methods offer carbon storage forms with durabilities spanning centuries or millennia, such as geological storage in deep formations or mineralization in rocks and construction materials, making them especially valuable for offsetting residual fossil emissions that are difficult to eliminate by other means. However, it also warns that the massive deployment of these methods implies large demands for energy, infrastructure, minerals, water, and technical capacities, and that the extent to which these requirements are compatible with other sustainability goals is still being studied. For example, DACCS requires large amounts of electrical and thermal energy, meaning that deployment without a low-carbon footprint energy base could reduce or even negate net removals; likewise, the expansion of BECCS could compete for land and biomass with food production and ecosystem conservation if not designed with strict safeguards.
A large portion of the chapter is dedicated to explaining why estimates of costs and potentials differ so much between studies, identifying several causes. It notes that there are differences in the system boundaries used in life-cycle assessments, as some works incorporate only the stages directly associated with the CDR project while others also include upstream and downstream emissions and costs. It also highlights that there are varying assumptions regarding minimum durability and reversal risk management, which influence how each removal is valued economically and climatically, and that deployment scenarios start from very different baselines—for instance, considering BECCS only in agricultural waste plants versus imagining large dedicated biomass plantations, or assuming DACCS powered by renewable electricity versus fossil-derived electricity. The chapter concludes that these methodological differences generate wide ranges and that it is necessary to harmonize criteria and improve transparency so that comparisons between studies become more robust.
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