PLEA Network

8 September 2025, CarbonBrief: Guest post: How the role of carbon storage has been hugely overestimated. Removing carbon dioxide (CO2) from the atmosphere is widely expected to play a key role in meeting the goals of the Paris Agreement. But this will only be effective for slowing climate change if the CO2 can be stored securely and indefinitely. This requires “geological carbon storage”, where captured CO2 is injected deep underground, where it can stay trapped for thousands of years. While the current deployment of CO2 removal (CDR) technologies around the world is small, almost all facilities aim to store captured CO2 in sedimentary basins. However, in our study in Nature, we show that current policy approaches to using these formations on a larger scale could be suffering from a false sense of abundance. We find that – once technical, social and environmental risks are considered – the world’s available reserves of geological carbon storage are significantly more limited than most estimates suggest. Our research shows that, of nearly 12,000bn tonnes of CO2 (GtCO2) of theoretical carbon storage capacity, just 1,460GtCO2 is risk-free. Significantly, we find that, if all available safe carbon storage capacity were used for CO2 removal, this would contribute to only a 0.7C reduction in global warming. In short, geological carbon storage is not limitless – on the contrary, its practical potential is a rather scarce planetary resource.  Read more here