Underground CO2 storage: Feasible solution or climate illusion?

Underground CO2 storage, a key component of carbon capture and storage (CCS) technology, is often viewed as a vital solution to combat climate change. In light of the urgency to address global warming, many potential methods of carbon capture have been meticulously investigated.

While the concept of storing CO2 underground is promising, recent research from Imperial College London highlights significant limitations and challenges associated with scaling up this technology.

Current international scenarios for limiting global warming to less than 1.5 degrees Celsius by 2100 rely heavily on technologies that can remove CO2 from the Earth’s atmosphere at unprecedented rates.

These strategies aim to remove between 1 and 30 gigatons of CO2 annually by 2050. However, the estimates for how quickly these technologies can be deployed have been largely speculative.

The Imperial study indicates that existing projections are not likely feasible at the current pace of development.

Uncertainty in storage projections

“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 Yuting Zhang, lead author 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 experts found that storing up to 16 gigatons of CO2 underground annually by 2050 is possible, but would require a substantial increase in storage capacity and scaling that current investment and development levels do not support.

Realistic plans for CO2 storage

While the UK Government has aspirations to position Britain as a clean energy superpower through initiatives like CCS, the research emphasizes the need to align such ambitions with realistic objectives for the safe and effective storage of CO2.

“Although storing between six to 16 gigatons of CO2 per year to tackle climate change is technically possible, these high projections are much more uncertain than lower ones,” noted co-author Dr. Samuel Krevor, also from Imperial’s Department of Earth Science and Engineering.

“This is because there are no existing plans from governments or international agreements to support such a large-scale effort. However, five gigatons of carbon going into the ground is still a major contribution to climate change mitigation.”

Modeling CO2 storage

The researchers developed models to show how quickly carbon storage systems could realistically be scaled up, taking into account factors such as suitable geology, economic limitations, and technological feasibility.

These models suggest that while it is possible to reduce CO2 emissions on a large scale, the path to achieving this and the contribution from key regions might diverge significantly from current projections.

For example, the study questions the overly optimistic projections often found in Intergovernmental Panel on Climate Change (IPCC) reports, particularly for countries like China, Indonesia, and South Korea, where current development is low.

“While integrated assessment models play an important role in helping climate policymakers make decisions, some of the assumptions they make when it comes to storing large amounts of carbon underground appear unrealistic,” noted study co-author Professor Christopher Jackson from Imperial’s Department of Earth Science and Engineering.

“Our findings suggest that more attainable and accurate benchmarks are needed to guide policy and investment.”

Setting a realistic global benchmark

The team’s analysis suggests a more realistic global benchmark for underground CO2 storage might be in the range of 5-6 gigatons per year by 2050.

This projection aligns with growth patterns observed in existing industries, including mining and renewable energy.

By applying these historical growth patterns to CO2 storage, the researchers have developed a model that offers a more practical and reliable method for predicting how quickly carbon storage technologies can be scaled up.

“Our study is the first to apply growth patterns from established industries to CO2 storage,” explained Dr. Krevor. “By using historical data and trends from other sectors, our new model provides a realistic and practical approach for setting attainable targets for carbon storage, helping policymakers to make informed decisions.”

The research, funded by the Engineering & Physical Sciences Research Council (EPSRC) and the Royal Academy of Engineering, highlights the importance of setting realistic goals in the global effort to combat climate change.

While underground carbon storage presents a promising strategy, understanding its potential and limitations is crucial for making the best use of this technology.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–