Carbon Capture: Scaling Challenges Without Emission Reductions

As we conclude our series on carbon capture and storage (CCS) (and our four special weeks), it's crucial to address the scalability of this promising technology. While CCS holds potential for reducing CO2 emissions from industrial sources, significant hurdles prevent it from being a standalone solution to climate change. This article delves into the physical challenges of scaling CCS to the required level and emphasizes the critical importance of reducing emissions alongside technological advancements.

The Need for Large-Scale Carbon Capture

Every technology that is geared toward reducing our emissions or capturing the carbon we released in excess in the atmosphere need to scale in order to try to mitigate as much as possible the adverse effects of CO2 in the atmosphere. Let's look at the blunt challenges we truly face.

Current Emissions vs. Capture Capacity

Globally, we emit more than 50 billion tonnes of CO2 annually. To make a meaningful impact, CCS technologies would need to capture a significant portion of these emissions. However, current CCS projects collectively capture only about 40 million tonnes of CO2 per year, which is less than 0.1% of global emissions. This vast discrepancy highlights the enormous challenge of scaling CCS to the required level.

Estimates for Required Scale

To limit global warming to 1.5°C, the Intergovernmental Panel on Climate Change (IPCC) estimates that we need to capture and store around 10 billion tonnes of CO2 annually by 2050. This requires a dramatic increase in CCS capacity, far beyond current capabilities. The scale of infrastructure and technological advancements needed to reach these levels is unprecedented, posing significant barriers.

Physical Challenges in Scaling CCS

But can we scale to the required level?

Volume and Space Requirements

Capturing and storing billions of tonnes of CO2 annually presents massive logistical challenges. The sheer volume of CO2 that needs to be captured and compressed is staggering. For example, 1 tonne of CO2 gas at standard temperature and pressure occupies approximately 556 cubic meters. Compressing this volume for transport and storage requires substantial infrastructure and energy. We're far from sure we can scale those operations with a net positive GHG emissions (meaning we will capture faster that we emit for these operations).

Storage Capacity

Identifying and certifying storage sites with adequate capacity for long-term CO2 storage is another significant challenge. Geological formations such as depleted oil and gas fields, saline aquifers, and basalt formations are potential storage sites. However, the global storage capacity is not evenly distributed, and suitable sites may not be available near major emission sources. Extensive geological surveys and long-term monitoring are necessary to ensure that CO2 remains securely stored, which adds to the complexity and scale of the task.

Infrastructure Needs

Developing the infrastructure required for large-scale CCS involves building extensive networks of pipelines to transport CO2 from capture sites to storage locations. For example, the United States alone would need tens of thousands of miles of new pipelines to handle the projected volume of captured CO2. Building this infrastructure involves significant time, resources, and coordination among various stakeholders. However, with somewhat limited resources, we will need some arbitrage and nothing is far from sure that the balance will be in favor or carbon capture!

Energy Intensity

Carbon capture processes, especially those using chemical solvents like amines, are highly energy-intensive. The energy required to capture, compress, transport, and store CO2 can offset the benefits of capturing it, particularly if the energy comes from fossil fuels. This additional energy demand poses a significant barrier to the efficiency and feasibility of large-scale CCS implementation.

The Urgency of Reducing Emissions

Despite all optimism from technolutionists, which is more hopecasting that anything else, we need to urgently reduce emissions in developped economies (emerging ones are generally below the accepted levels of carbon emissions and should not embark, so far, in dramatic carbon reduction, but this is another topic).

Emission Reduction Targets

While CCS is a vital tool in reducing emissions from industrial sources, it is not a silver bullet for climate change. The IPCC recommends reducing emissions by approximately 5% annually to meet the targets set by the Paris Agreement. This reduction is essential to avoid the worst impacts of climate change and requires immediate and substantial action. This is true for all economies though as shown in the interesting study, Greenhouse gas emissions and reduction strategies for the world's largest greenhouse gas emitters :

"This research provides an overview of global GHG emissions from 1970 to 2022 for the world's most polluting countries: the United States, China, India, Russia, Brazil, Indonesia, Japan, Iran, Mexico, and Saudi Arabia. These countries collectively account for approximately 64% of GHG emissions. The aim is to understand the impact of various economic sectors, such as industry, energy, agriculture, and transportation, on overall emissions. The analysis highlights the disparity in per capita emissions, with smaller but major oil-producing countries in the Persian Gulf, such as Qatar and the United Arab Emirates, exhibiting high per capita emission levels, while more populated countries like the United States and South Korea show lower per capita values but significant total emission volumes. The study suggests that transitioning to renewable energy, improving energy efficiency in industry, promoting sustainable agriculture, reforestation, and electrifying transportation are key methods to achieve United Nations Sustainable Development Goals (UN SDG)."

Not a Standalone Solution

Relying solely on CCS without reducing overall emissions is insufficient to meet global climate targets. CCS must be integrated into a broader climate strategy that includes a significant increase in renewable energy deployment, energy efficiency improvements, and changes in consumption patterns. Only through a combined approach can we hope to achieve meaningful reductions in greenhouse gas emissions.

Combining Efforts

Combining CCS with other technologies and strategies can enhance its effectiveness. For instance, integrating CCS with bioenergy (BECCS) can create a net-negative emission system, where CO2 is removed from the atmosphere. Additionally, policies promoting energy efficiency and the adoption of renewable energy sources can reduce the overall need for CCS, making it more manageable and cost-effective.

The physical challenges facing the implementation of carbon capture technologies are significant and multifaceted. The enormous volume of CO2 that needs to be captured and stored, the extensive infrastructure requirements, and the high energy intensity all pose barriers to the widespread adoption of CCS. While it is a necessary technology for reducing industrial emissions, CCS alone is not enough to mitigate the carbon emissions needed to curb climate change.

Governments, industries, and individuals must act now to reduce emissions significantly. Waiting for CCS to scale up without making immediate and substantial emission reductions risks locking in catastrophic climate impacts. We must leverage all available tools and technologies while prioritizing the urgent need to cut emissions by 5% annually. Only through a comprehensive approach that includes renewable energy, energy efficiency, and behavioral changes can we create a sustainable and effective climate strategy.

References

1. Boundary Dam Carbon Capture Project
2. International Energy Agency (IEA) CCS Overview
3. National Energy Technology Laboratory on Carbon Removal
4. IPCC Special Report on Carbon Dioxide Capture and Storage
5. World Resources Institute on Comprehensive Climate Strategy
6. Greenhouse gas emissions and reduction strategies for the world's largest greenhouse gas emitters .

This article has been written with the help of above resources and ChatGPT-4o.