Study Exposes Limits of Underground CO2 Storage as a Climate Change Strategy
According to new research from Imperial College London, there are limits to how quickly humanity can store gigatons of carbon dioxide to combat climate change.
The 2015 Paris Climate Agreement, under which world leaders expressed their commitment to prevent global temperatures rising by more than 1.5C, relies on technologies, the research team points out, that removes carbon dioxide from the Earth’s atmosphere faster than humans can release it. However, this entails removing CO2 at a rate of 1-30 gigatonnes per year by 2050 and existing projections are “unlikely to be feasible at the current rate of growth.”
It might be possible by 2050, per the study, to store up to 16 gigatonnes of CO2 underground each year but this target cannot be reached without increasing storage capacity on a massive scale and scaling it over the coming decades. But investment, development and deployment is not moving at the pace required to make this a reality. The team's estimates indicate that a more achievable global target is around 5-6 gigatonnes of carbon storage annually by 2050, a projection based on the historical scaling patterns of comparable technologies.
The results, published in Nature Communications, highlight the critical need to align ambitious initiatives with practical goals for how rapidly CO2 can be safely stored underground, counterbalancing messaging from the UK government to make Great Britain a world leader in the realm of clean energy. The nation is making significant progress in its transition to clean energy and the World Economic Forum previously reported that “40% of the UK's electricity in 2022 was made up of solar, wind, biomass and hydropower.”
Researchers from Imperial's Department of Earth Science and Engineering designed simulations to project how swiftly carbon storage systems could be built and implemented, considering factors such as the presence of viable geological formations, as well as technical and financial constraints on expansion.
The findings indicate that while large-scale CO2 emission reductions are attainable, the route to accomplishing this and the role of critical regions may vary significantly from current projections, including those outlined in Intergovernmental Panel on Climate Change (IPCC) reports.
"There are many factors at play in these projections, including the speed at which reservoirs can be filled as well as other geological, geographical, economic, technological, and political issues,” said lead author Yuting Zhang, from Imperial's Department of Earth Science and Engineering. “However, more accurate models like the ones we have developed will help us understand how uncertainty in storage capacity, variations in institutional capacity across regions, and limitations to development might affect climate plans and targets set by policymakers."
The scientists uncovered that the IPCC had incorporated findings from integrated assessment models (IAMs)—sophisticated instruments that amalgamate diverse data sources to forecast the effects of carbon sequestration methods on both climate and economy—which tend to significantly overestimate the volume of CO2 that can be stored underground.
Specifically, the study indicates that the projections in IPCC reports for Asian nations such as China, Indonesia, and South Korea—where current development levels are minimal—assumed deployment rates that are implausible. This suggests that the existing forecasts are improbable and not dependable.
