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There are water consequences across every life cycle stage of coal‐fired electricity consumption, from production and processing to combustion, which have not been studied with regional specificity. There is often a spatial decoupling between where coal is produced and processed versus where it is combusted for power generation, complicating any analysis to estimate the life cycle water implications of electricity consumption. Furthermore, electricity generated by coal‐fired power plants can be consumed within its own balancing authority or exported to another balancing authority. This analysis spatially resolves the water consumed and water withdrawn for coal mining, coal preparation, and power plant cooling from 1) where the coal is mined to where the coal is burned for power production and 2) where the electricity is generated to where the electricity is consumed. Although the largest portion of coal consumed came from the Northern Great Plains province, coal from this region consumes the least amount of water for mining and preparation compared with other provinces. Water withdrawals for cooling power plants within each balancing authority are driven by cooling technology. Due to the interconnected grid, there can be differences between attributing water footprint at the producer level versus the consumer level.
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A regional assessment of the water embedded in the US electricity system
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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- Award ID(s):
- 1632945
- PAR ID:
- 10305347
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research Letters
- Volume:
- 14
- Issue:
- 8
- ISSN:
- 1748-9326
- Page Range / eLocation ID:
- Article No. 084014
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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