1. The water footprint of carbon capture and storage technologies.
- Author
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Rosa, Lorenzo, Sanchez, Daniel L., Realmonte, Giulia, Baldocchi, Dennis, and D'Odorico, Paolo
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CLIMATE change mitigation , *ECOLOGICAL impact , *WATER shortages , *WATER supply , *WATER consumption , *CARBON sequestration , *GEOLOGICAL carbon sequestration - Abstract
Carbon capture and sequestration (CCS) is an important technology to reduce fossil CO 2 emissions and remove CO 2 from the atmosphere. Scenarios for CCS deployment consistent with global climate goals involve gigatonne-scale deployment of CCS within the next several decades. CCS technologies typically involve large water consumption during their energy-intensive capture process. Despite potential concerns, the water footprint of large-scale CCS adoption consistent with stringent climate change mitigation has not yet been explored. This study presents the water footprints (m3 water per tonne CO 2 captured) of four prominent CCS technologies: Post-combustion CCS, Pre-combustion CCS, Direct Air CCS, and Bioenergy with CCS. Depending on technology, the water footprint of CCS ranges from 0.74 to 575 m3 H 2 O/tonne CO 2. Bioenergy with CCS is the technology that has the highest water footprint per tonne CO 2 captured, largely due to the high water requirements associated with transpiration. The widespread deployment of CCS to meet the 1.5 °C climate target would almost double anthropogenic water footprint. Consequently, this would likely exacerbate and create green and blue water scarcity conditions in many regions worldwide. Climate mitigation scenarios with a diversified portfolio of CCS technologies have lower impacts on water resources than scenarios relying mainly on one of them. The water footprint assessment of CCS is a crucial factor in evaluating these technologies. Water-scarce regions should prioritize water-efficient CCS technologies in their mitigation goals. In conclusion, the most water-efficient way to stabilize the Earth's climate is to rapidly decarbonize our energy systems and improve energy efficiency. • Carbon capture and storage involve large green and blue water consumption. • Large-scale deployment of carbon capture and storage could double the water footprint of humanity. • Trade-offs between climate mitigation benefits and water resources should be weighed. • Carbon capture and storage should be prioritized in regions not affected by water scarcity. • Water sustainability should be accounted for in carbon dioxide removal policies. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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