Future Power Generation Could Further Endanger Water Supplies

The country stands at a critical moment when it can dramatically lower the power industry's draw on the nation's strained water supply by replacing its aging power plants with water-smart options like renewable energy and efficiency, according to a study released today by the Union of Concerned Scientists-led (UCS) Energy and Water in a Warming World Initiative (EW3). The report warns that continuing down a business-as-usual path will place a heavy burden on the nation's overly-taxed water resources.

"Making low-carbon, water-smart choices is a high-stakes effort. The choices we make in the near term to define the power sector of this century will affect water resources, our climate and long-term hydrology, and the power sector's long-term resilience," said Peter Frumhoff, UCS's director of science and policy and chair of the project's Scientific Advisory Committee. "We set electricity and water on a collision course years ago. Now we must build a power system hard-wired not for risk, but for resilience."

More than 40 percent of U.S. freshwater withdrawals are used for power plant cooling. These plants also lose several billion gallons of freshwater every day through evaporation. Further, increasing demand and drought are putting a greater strain on water resources. Low water levels and high water temperatures can cause power plants to cut their electricity output in order to avoid overheating or harming local water bodies. Such energy and water collisions can leave customers with little or no electricity or with added costs because their electric supplier has to purchase power from elsewhere, as occurred during the past two summers.

Low natural gas prices and a rash of retirements of old and uncompetitive coal-fired power plants have prompted significant change in the power industry. The UCS-led study, Water-Smart Power: Strengthening the U.S. Electricity System in a Warming World, found the choices the industry makes now will decide how much the energy sector will tax the nation's threatened water supplies and contribute to climate change in the decades to come.

"Our electricity system clearly isn't able to effectively meet our needs as we battle climate change and face a future of expanding electricity demand and increasing water strain," said Erika Spanger-Siegfried, co-author of the report and a senior analyst in the UCS Climate & Energy Program. "As old plants are retired or retrofitted and new plants are built, we've got to untangle our competing demands for water and energy."

Examining different paths the nation's electricity production can take in the coming decades, the study found that while utilities' ongoing shift to natural gas would decrease water use in the coming decades, its ongoing requirements could still harm water-strained areas. This shift to natural gas also would do little to lower the power sector's carbon emissions.

"Under the industry's current -- or business-as-usual -- path, emissions would stay within 5 percent of current levels and water withdrawals would not drop significantly until after 2030," said John Rogers, co-manager of EW3 and a senior energy analyst with UCS's Climate and Energy Program. "In our water-constrained world, a 20-year delay in tackling the problem leaves the power industry unnecessarily vulnerable to drought and exacerbates competition with other water users. We can bring water use down faster and further, but only by changing how we get our electricity."

A pathway that includes strong investments in renewables and energy efficiency, according to the study, would greatly reduce power generation's water use and carbon emission. Under such a scenario, water withdrawals would drop by 97 percent from current levels by 2050, with most of that drop within the next 20 years. That approach would also cut carbon emissions 90 percent from current levels, mostly in the near term. A renewables path would also be a much cheaper path for consumers, the report found.

"We have a tremendous opportunity before us," said Robert Jackson, an environmental scientist at Duke University. "By increasing energy efficiency and renewables, we can cut greenhouse gas emissions and water use, improve the quality of our water and air, and save money and lives at the same time. How often do we get a chance like that?"

The study concluded that many near-term options exist to reduce power sector water and climate risks. Options include prioritizing low-carbon, water-smart energy choices, such as renewable energy and energy efficiency; upgrading power plant cooling systems with technologies that ease local water stress; and instituting integrated resource planning that connects energy and water decision making.