In ars (S.2967), which directs the Massachusetts Clean Energy Center (MassCEC) to conduct and publish a study on the “prospects and opportunities for carbon dioxide removal (CDR) innovation and operations within the commonwealth or in waters not more than 50 nautical miles off the commonwealth.” CDR refers to human activities that remove carbon dioxide (CO₂) from the atmosphere and durably store it in geological, terrestrial, or ocean reservoirs, or in products. Unlike emissions reductions, which prevent new CO₂ from entering the atmosphere, CDR focuses on removing CO₂ that is already present. CDR is a broad term that encompasses a diverse range of pathways that differ in their underlying mechanisms, maturity, reversal risk, and cost. RMI was contracted by MassCEC to conduct this study.

The Massachusetts Carbon Dioxide Removal Study (this Study) builds on Massachusetts’ prior planning to assess which CDR pathways are most feasible and scalable in the state’s policy, economic, and natural resource context. The outcomes of this effort will inform future iterations of the state’s Clean Energy and Climate Plans (CECPs), which are the flagship climate planning documents, to provide an assessment of best practices and policy options that Massachusetts should consider when responsibly integrating CDR into its net-zero strategy.

This Study describes and assesses 23 CDR and storage pathways across several characteristics, analyzing their suitability for deployment and research and development (R&D) leadership in Massachusetts. Main findings include the following.

• Many CDR pathways may be suitable for deployment by midcentury in Massachusetts at a scale that is significant relative to Massachusetts’s need. 14 million tCO₂e per year of removals will likely be needed by 2050. If a pathway is able to meet over 7% of those 14 million tCO₂e, or about 1 million tCO₂ per year, it is considered to have at least a medium scale potential relative to Massachusetts’ need.

• It is likely that Massachusetts could be a leader in R&D and innovation for seven pathways, ranging across biogenic, geochemical, and synthetic CDR, as well as storage.

• Even with the opportunities for deployment and R&D leadership, it is unlikely that deployment of CDR solely within the state can achieve its likely total need.

• Additional emissions reductions, regional coordination, and out-of-state procurement of CDR will likely be needed for Massachusetts to achieve it Net Zero 2050 mandate.

This Study identifies policy interventions from other jurisdictions that Massachusetts could learn from to support responsible innovation and deployment of CDR in support of its climate and economic goals. These interventions should be assessed during the forthcoming 2035 CECP process in consideration with other policy priorities and resource capacity.