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Abstract Water consumption from electricity systems can be large, and it varies greatly by region. As electricity systems change, understanding the implications for water demand is important, given differential water availability. This letter presents regional water consumption and consumptive intensities for the United States electric grid by region using a 2014 base year, based on the 26 regions in the Environmental Protection Agency’s Emissions & Generation Resource Integrated Database. Estimates encompass operational (i.e. not embodied in fixed assets) water consumption from fuel extraction through conversion, calculated as the sum of induced water consumption for processes upstream of the point of generation (PoG) and water consumed at the PoG. Absolute water consumption and consumptive intensity is driven by thermal power plant cooling requirements. Regional consumption intensities vary by roughly a factor of 20. This variability is largely attributed to water consumption upstream of the PoG, particularly evaporation from reservoirs associated with hydroelectricity. Solar and wind generation, which are expected to continue to grow rapidly, consume very little water and could drive lower water consumption over time. As the electricity grid continues to change in response to policy, economic, and climatic drivers, understanding potential impacts on local water resources can inform changes.
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Spatially and Temporally Detailed Water and Carbon Footprints of U.S. Electricity Generation and Use
Abstract Electricity generation in the United States entails significant water usage and greenhouse gas emissions. However, accurately estimating these impacts is complex due to the intricate nature of the electric grid and the dynamic electricity mix. Existing methods to estimate the environmental consequences of electricity use often generalize across large regions, neglecting spatial and temporal variations in water usage and emissions. Consequently, electric grid dynamics, such as temporal fluctuations in renewable energy resources, are often overlooked in efforts to mitigate environmental impacts. The U.S. Department of Energy (DOE) has initiated the development of resilient energyshed management systems, requiring detailed information on the local electricity mix and its environmental impacts. This study supports DOE's goal by incorporating geographic and temporal variations in the electricity mix of the local electric grid to better understand the environmental impacts of electricity end users. We offer hourly estimates of the U.S. electricity mix, detailing fuel types, water withdrawal intensity, and water consumption intensity for each grid balancing authority through our publicly accessible tool, the Water Integrated Mapping of Power and Carbon Tracker (Water IMPACT). While our primary focus is on evaluating water intensity factors, our dataset and programming scripts for historical and real‐time analysis also include evaluations of carbon dioxide (equivalence) intensity within the same modeling framework. This integrated approach offers a comprehensive understanding of the environmental footprint associated with electricity generation and use, enabling informed decision‐making to effectively reduce Scope 2 water usage and emissions.
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- Award ID(s):
- 2144169
- PAR ID:
- 10576968
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Water Resources Research
- Volume:
- 60
- Issue:
- 12
- ISSN:
- 0043-1397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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