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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 This analysis spatially resolves the water consumed and water withdrawn for coal mining, coal preparation, and power plant cooling from 1) where the coal is mined to where the coal is burned for power production and 2) where the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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Hydroclimate risk to electricity balancing throughout the U.S
Abstract Although hydropower produces a relatively small portion of the electricity we use in the United States, it is a flexible and dispatchable resource that serves various critical functions for managing the electricity grid. Climate-induced changes to water availability will affect future hydropower production, and such changes could impact how the areas where the supply and demand of electricity are balanced, called balancing authority areas, are able to meet decarbonization goals. We calculate hydroclimate risk to hydropower at the balancing authority scale, which is previously underexplored in the literature and has real implications for decarbonization and resilience-building. Our results show that, by 2050, most balancing authority areas could experience significant changes in water availability in areas where they have hydropower. Balancing areas facing the greatest changes are located in diverse geographic areas, not just the Western and Northwestern United States, and vary in hydropower generation capacity. The range of projected changes experienced within each balancing area could exacerbate or offset existing hydropower generation deficits. As power producers and managers undertake increasing regional cooperation to account for introducing more variable renewable energy into the grid, analysis of risk at this regional scale will become increasingly salient.
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- PAR ID:
- 10557111
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research: Infrastructure and Sustainability
- Volume:
- 4
- Issue:
- 4
- ISSN:
- 2634-4505
- Format(s):
- Medium: X Size: Article No. 045006
- Size(s):
- Article No. 045006
- Sponsoring Org:
- National Science Foundation
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