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Abstract To achieve net zero carbon emissions by mid-century, the United States may need to rely on carbon dioxide removal (CDR) to offset emissions from difficult-to-decarbonize sectors and/or shortfalls in near-term mitigation efforts. CDR can be delivered using many approaches with different requirements for land, water, geologic carbon storage capacity, energy, and other resources. The availability of these resources varies by region in the U.S. suggesting that CDR deployment will be uneven across the country. Using the global change analysis model for the United States (GCAM-USA), we modeled six classes of CDR and explored their potential using four scenarios: a scenario where all the CDR pathways are available (Full Portfolio), a scenario with restricted carbon capture and storage (Low CCS), a scenario where the availability of bio-based CDR options is limited (Low Bio), and a scenario with constraints on enhanced rock weathering (ERW) capabilities (Low ERW). We find that by employing a diverse set of CDR approaches, the U.S. could remove between 1 and 1.9 GtCO2/yr by midcentury. In the Full Portfolio scenario, direct air carbon capture and storage (DACCS) predominates, delivering approximately 50% of CO2removal, with bioenergy with carbon capture and storage contributing 25%, and ERW delivering 11.5%. Texas and the agricultural Midwest lead in CDR deployment due to their abundant agricultural land and geological storage availability. In the Low CCS scenario, reliance on DACCS decreases, easing pressure on energy systems but increasing pressure on the land. In all cases CDR deployment was found to drive important impacts on energy, land, or materials supply chains (to supply ERW, for example) and these effects were generally more pronounced when fewer CDR technologies were available.
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Status of CCS injection well regulation in the United States and correlates of project location and maturity
Abstract The number of carbon dioxide capture and sequestration (CCS) projects under development in the United States increased sharply following the passage of the Inflation Reduction Act in 2022. The 168 applications subsequently filed with the Environmental Protection Agency reflect projects that are unevenly spread geographically and vary in maturity. Here we summarize the heterogeneous regulatory environment for approval of injection wells across the country and examine whether there is a relationship between the existence and maturity of injection well applications and a range of factors that could affect the development process. These factors include EPA region, state primacy, geologic resources for sequestration, point source carbon dioxide (CO2) emissions, public land ownership, pore space legislation, and community characteristics. We find that CCS project approvals have not matched the pace of application submissions and there is wide geographic variation in siting. We find evidence that EPA region and state primacy are associated with project maturity, while geologic resources, state pore space legislation, and county-level racial group shares are associated with project location. While we make no causal claims, we find with statistical significance that sequestration sites are more frequently located in counties with higher non-White populations. We find no clear relationship between state CO2emissions, public land ownership, or median household income with either project location or maturity.
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- Award ID(s):
- 2230743
- PAR ID:
- 10657206
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research: Energy
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2753-3751
- Format(s):
- Medium: X Size: Article No. 045021
- Size(s):
- Article No. 045021
- Sponsoring Org:
- National Science Foundation
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