Meeting Carbon Dioxide Removal Demand in 2030: The Potential of Macroalgae Cultivation and Harvest

A growing number of countries have announced net-zero and net-negative emissions targets, but only a few countries provide incentives for carbon dioxide removal (CDR). We derive estimates of countries' hypothetical demand for CDR in 2030 based on their emissions reduction targets under the Paris Agreement. The aggregated average global demand for CDR in the compliance year 2030 is 1064 MtCO2, 353 MtCO2, and 124 MtCO2 for the low, medium, and high-cost CDR scenarios, respectively. This demand comes exclusively from countries and regions with relatively high GDP per capita, relatively high abatement costs and a limited supply of removals from afforestation. In a scenario with full international emissions trading, CDR demand until 2030 would drop to zero. Thus, the near-term demand for CDR is primarily driven by fragmented, inefficient climate policies. As there will be no functioning system of international emissions trading in the near future, regions with ambitious climate targets and high abatement costs, such as Canada, Japan, the United Kingdom, and the European Union, will already have significant CDR demand in 2030. Marine CDR methods such as macroalgae cultivation and harvesting could make a small but relevant contribution to meeting this demand. However, given the lead time required to achieve reasonable carbon sequestration efficiencies, a forward-looking climate policy would begin to incentivize and develop such methods now, so that areas within countries' exclusive economic zones can be developed for this purpose.