The Energy-Water Connection
Energy production requires a reliable, abundant, and predictable source of water, a resource that is already in short supply throughout much of the United States and the world. The electricity industry is second only to agriculture as the largest user of water in the United States. Electricity production from fossil fuels and nuclear energy requires 190,000 million gallons of water per day, accounting for 39% of all freshwater withdrawals in the nation, with 71% of that going to fossil-fuel electricity generation alone.
Coal, the most abundant fossil fuel, currently accounts for 52% of U.S. electricity generation, and each kWh generated from coal requires 3.3 gallons of water. That means U.S. citizens may indirectly depend on as much water turning on the lights and running appliances as they directly use taking showers and watering lawns. According to the Bush administration's 2001 National Energy Policy, our growing population and economy will require 393,000 MW of new generating capacity (or 1,300 to 1,900 new power plants—more than one built each week) by the year 2020, putting further strain on the nation's water resources.
Several related factors bring into question whether a stable, affordable supply of water will exist to support the nation's future electricity demands.
While the U.S. population is expected to increase significantly, accessible freshwater supplies are not. Moreover, population movement and energy demand do not always track well with water availability. During the 1990s, the largest regional population growth (25%) in the United States occurred in one of the most water-deficient regions, the Mountain West. Water availability is also becoming a serious issue in the Southeast, where population has increased by nearly 14% since 1990. By comparison, the water-rich northeast has experienced only a 2% growth in population.
Issues
An increasing population not only will need more electricity but also more food, pushing the nation's two largest water users into potential competition for limited water resources.
Proposed restrictions on the use of water for power generation to protect fish and other aquatic organisms could result in increased costs of electricity or potential energy shortages.
Because the energy required for treatment and delivery of water accounts for as much as 80% of its cost, an insufficient supply of affordable energy will have a negative impact on the price and availability of water.
The interdependency between the water and carbon cycles could lead to shifts in water distribution that are difficult to predict. That is, increases in electricity production – and use – may lead to higher levels of atmospheric carbon, which can impact the availability of water to electricity producers in certain regions.
In summary, the link between clean, affordable energy and clean, affordable water is crystal clear. There cannot be one without the other.
For additional resources and reference material, please access these online resources that discuss this topic.
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