Coleman et al. [Preprint]: Quantifying baseline costs and cataloging potential optimization strategies for kelp aquaculture carbon dioxide removal
Struan Coleman, Tobias Dewhurst, David W. Fredriksson, Adam St. Gelais, Kelly L. Cole, Michael MacNicoll, Eric Laufer, Damian Brady IN: Front. Mar. Sci., Sec. Marine Fisheries, Aquaculture and Living Resources, doi: 10.3389/fmars.2022.966304
The authors take a detailed look at the economics of growing and sinking massive amounts of seaweed in the ocean as a means of permanently sequestering carbon. They find that the cost of kelp-based CDR in their model system is more than $17k per ton of CO₂. After careful optimization, this could drop as low as $1,200/ton, still many times higher than the Energy Department’s goal of $100/ton. Why so expensive? Unsurprisingly, building floating farms that can handle the wind and waves of the ocean is hard. But kelp farms also face more mundane challenges. Like all carbon removal solutions, decarbonizing the supply chain and improving methods for monitoring, reporting, and verification (MRV) are musts in order for this solution to become efficient and cheap enough for prime time.