The Global CCS Institute is sharing a letter submitted to Nature (journal) in response to the recent study by Gidden et al., “A prudent planetary limit for geologic carbon storage.”
The correspondence offers expert perspective on the study’s findings, drawing on operational experience from CCS projects worldwide. It highlights the urgency of deploying CCS at scale and underscores that timely action is critical to meeting global climate objectives.
The recent study from Gidden et al. published in Nature (“A prudent planetary limit for geologic carbon storage”) provides a timely reassessment of global CO₂ storage capacity that reinforces the urgent need for immediate deployment. While their conservative estimate of 1,460 GtCO₂ storage capacity is lower than some previous assessments, it aligns closely with IPCC conclusions and confirms that geological storage remains more than sufficient for CCS to play a crucial role in limiting global warming. The study’s finding that CCS could reduce warming by 0.7°C, even under restrictive assumptions, demonstrates its continued necessity, particularly for hard-to-abate industrial sectors like cement, steel, and chemicals where scalable alternatives remain limited.
While we agree with some of the key conclusions, the study’s methodology applies overly restrictive assumptions about risk and technical parameters of CCS projects. In fact, some of those assumptions contradict real-world operational and project experience. For example, their depth limits of 2,500 meters for subsurface storage ignore successful projects like Northern Lights operating at 2,600 meters, while their 300-meter ocean depth restriction overlooks Brazil’s decade-long experience with CO2 injection at 2,000-meter water depths. The study’s 25km buffer zone around populated areas also appears conservative when compared to operational experience and discordant with the typical approach to permitting. CarbFix operates at 8km from populated areas and Shell Quest at 15km. Existing projects demonstrate through rigorous permitting and risk assessments that high safety standards can be met in practice.
The Institute would generally agree that the research correctly frames geological storage as a finite intergenerational resource requiring strategic management. This supports prioritising CCS for essential applications – industrial point sources that cannot be electrified and durable carbon removal technologies. The critical question is not whether adequate storage capacity exists, but rather the speed at which it can be utilised at scale.
Immediate action is imperative: delaying CCS implementation not only jeopardises achieving near-term climate targets, but compounds the future storage requirements and operational complexity needed to meet climate goals. This study reinforces that every year of delay makes climate goals more difficult and expensive to achieve.
Rather than constraining CCS ambitions, this research should galvanise efforts to reach the critical 1 GtCO₂ storage target by 2030. Early deployment will provide the operational data needed to refine future capacity estimates and develop robust legal and regulatory frameworks essential for safe, long-term storage operations. The window for effective climate action is narrowing and CCS deployment remains essential to achieving a net-zero future.
