An electrochemical technology might be a solution to combat ocean acidification and remove carbon dioxide from the atmosphere. With the support of the Carbon to Sea initiative, researchers from McMaster University and the University of Toronto have developed the ingenious technology.
The innovation could have far-reaching implications for mitigating the catastrophic effects of global warming. The team’s breakthrough is even more relevant given the alarming increase in CO2 emissions over the past six decades.
This has corresponded with a 30% rise in ocean acidity. The sharp increase is now posing a grave threat to marine life and ecosystems, particularly coral reefs.
According to an article written by the study’s authors in The Conversation, only 45% of carbon dioxide emissions remain in the atmosphere; the remainder is absorbed through two cycles: 1) the biological carbon cycle stores CO2 in plant matter and soils, and 2) the aqueous carbon cycle absorbs CO2 from the atmosphere into the oceans. Each of these cycles accounts for 25% and 30% of emitted CO2, respectively.
Consequently, scientists have explored various methods to address this issue. One of the methods they have tried is ocean alkalinity enhancement. This innovation aims to restore the ocean’s pH balance while simultaneously absorbing excess CO2 from the atmosphere.
Traditionally, adding alkali minerals directly into the ocean has been considered, but the sheer scale required for this approach poses challenges. Estimates suggest that we would need to introduce a mass of roughly eight thousand Empire State Buildings’ worth of alkaline substance into the oceans.
And this is just to scratch the surface of IPCC emissions targets. This alone won’t suffice.
An electrochemical approach
Enter bipolar membrane electrodialysis. This electrochemical approach removes seawater acidity without the need for additional substances. Powered by decarbonized energy, the method offers a simple, modular, and potentially cost-effective means of carbon dioxide removal.
A small-scale BMED system was developed to test in collaboration with the Palo Alto Research Center and X Development in 2015. This system showed promising results. The results were even more astounding when integrated with existing facilities such as desalination plants.
Despite initial success, a few obstacles have prevented the widespread adoption of BMED technology. For one, there is the high cost and limited lifespan of specialized membranes. However, ongoing research aims to overcome these challenges. The plan is to create scalable, ultra-thin membranes that can efficiently extract acidity while reducing production and operational costs.
Several start-ups, including Ebb Carbon, SeaO2, and Vesta, are also addressing ocean carbon dioxide removal through OAE. Entrepreneurial interest is high in these projects. All in all, targeting OAE solutions hinges on massive support from various stakeholders, including government agencies, industries, non-profits, and venture capitalists.
