Can human engineering play a supporting role to nature? That’s a question that grows in relevance and urgency, given the gap between where global emissions stand and where they need to be, posthaste. The sheer quantity of excess greenhouse gases means natural processes can’t do it all when it comes to carbon sequestration. Select nascent technologies show some promise to supplement terrestrial, coastal, and ocean sinks.
Remove carbon. Do something with it. Those are the central premises of engineered sinks. Remove can mean pulling carbon from the concentrated exhaust of a power plant or industrial process, which falls under the umbrella of “carbon capture.” Remove can also mean pulling carbon out of the air, where it’s much less concentrated.
Where carbon goes next is the other critical piece of the equation. It can be stored or buried—pairing “capture” and “storage.” Carbon can also be used—cycled quickly, perhaps for adding bubbles to a beverage or to make more sustainable jet fuels. Or it can be locked up for a long while, perhaps in concrete or through the ancient practice of baking biomass into biochar, then buried. This so-called “semi-permanent sequestration” is most powerful.
Could recaptured carbon become a commodity? Something of value? Perhaps. For now, solutions in this sector are “coming attractions,” and issues of cost, scale, and the energy required all remain in the balance.
NOTE: Project Drawdown has assessed a very limited set of solutions for engineered sinks to date. This solution set will expand in the future (e.g., direct air capture).