Humans are releasing dangerous amounts of carbon dioxide into the atmosphere, and we are beginning to feel its effects. Weather is becoming more extreme, ice caps are melting, and oceans are acidifying. The Intergovernmental Panel on Climate Change continues to release reports that warn of the disastrous future that lies ahead if we collectively fail to act on climate change. It has also become clear that there is no single fix to climate change, and that we must implement a multitude of strategies in order to get the world’s climate back on track for future generations.
One such strategy for mitigating our CO2 output is carbon capture and sequestration, or CCS. The goal of CCS is to capture CO2, either from point sources or from the ambient air, and store it where it cannot escape, essentially removing CO2 from our atmosphere. The most efficient way to implement CCS is at point sources, such as power plants. By installing CO2 scrubbers on smokestacks, much of the escaping CO2 is filtered out and ready to be transported and stored underground where it can’t escape. A major advantage of this strategy is that current power plants can be retrofitted with this technology. However, CO2 scrubbers are expensive, raising the question of whether that money should be spent to retrofit a coal-powered power plant or invested in our transition to renewable energy.
Scrubbing CO2 from point sources like smokestacks is one thing, but how do we sequester the immense amounts of CO2 that have already been emitted into our atmosphere? Many biological processes and ecosystems naturally sequester and store CO2, including forests, wetlands, and oceans. It should remain a priority to protect these natural CO2 stores, but clearly human activity has exceeded natural bounds.
A more recent and controversial CCS technology, named direct air capture, has entered the conversation. This strategy aims to filter mass amounts of ambient air through a filter in order to remove CO2. While this technology seems logical and exciting, it has been expensive in its current state. The sheer amount of air that must be filtered in order to access the dilute amount of CO2 in our atmosphere is immense, and requires an incredible energy input, often from fossil fuels. We should not regard direct air capture as an answer to the excess of CO2 in our atmosphere; we should instead see it as an exciting technology that is still in its infancy and requires additional research and development.
Carbon capture and sequestration technology can be used to both help and hurt the environment. It turns out that injecting carbon dioxide into oil fields can release additional crude oil that would otherwise be nearly impossible to extract. This strategy is called enhanced oil recovery, and is used to recover an additional 10–15 percent of crude oil yields in large-scale oil operations. As we decide how to develop and implement CCS technology in the future, it is important to consider the ways in which it can be used to help solve the climate crisis and also contribute to it.
Carbon capture and sequestration technology has the potential to contribute to the climate change solution, but not in its current state. An immense amount of collaboration between researchers, engineers, and scientists is necessary if CCS is to become a viable and cost-effective means of addressing the excess of CO2 in our atmosphere. Still, CCS marks an exciting time in which human ingenuity is mimicking natural processes in order to address the largest and most looming problem facing the planet.