Western Drought Steals Clean Energy Along With Fresh Water At Power Plants

Via the Washington Post, a look at the southwest US drought’s watergy impact:

The floor rumbled under Mark Cook. His legs vibrated as he stood in a tunnel tucked into the thick base of Hoover Dam, 430 feet below the tourists looking out over Lake Mead. Beneath him, water roared through steel pipes 13 feet tall. Nearby, heavy turbines hummed with mechanical intensity.

“We’re moving some good water today,” Cook, the dam manager, said proudly.

Moving water means making electricity. But the drought is making that harder to do. The lack of water has put a serious crimp in the hydroelectric line at Hoover Dam and other power plants across the West, limiting an inexpensive and pollution-free energy source that once was considered endless.

Power capacity at Hoover Dam, on the Arizona-Nevada border, has dropped nearly 25 percent since 2000. In California, home to 287 hydroelectric plants and where almost half the state today is classified as being in “exceptional drought,” hydropower has fallen 60 percent in the past four years.

“The drought is taking a toll on power generation,” said Mike Connor, deputy secretary of the Interior Department.

Some power companies in California have raised rates as they turn to pricier, often dirtier energy sources. That makes it harder to reduce the greenhouse gases some blame for worsening the drought in the first place.

Meanwhile, the risk of brief summertime blackouts could rise: Hydroelectric plants often are called upon to help urban power grids deal with sudden spikes in demand.

The problem can be traced to shortages of rain and snowpack, which lead to shallower rivers and reservoirs, which result in less pressure to speed the water along. Slower water simply packs less punch. So turbines spin more slowly, generating less electricity.

Some small facilities, such as those along the Truckee River in northern Nevada, have shut down. Other plants are open but struggling. The 53 hydropower facilities run by the U.S. Bureau of Reclamation across the West are producing 10 percent less power than a few years ago, despite rising demand.

Lake Mead lies in the Colorado River basin, which has been mired in drought for more than a decade. Tree-ring studies suggest this is the region’s fourth-worst drought in 1,000 years.

Once the largest U.S. water reservoir, Lake Mead has faded to fourth place as it has lost water. In 2008, a Scripps Institution of Oceanography research paper asked the provocative question, “When Will Lake Mead Go Dry?” The study predicted the lake had a 50-50 shot at achieving that fate by 2021, given current trends.

 “The system is in deep trouble,” said Tim Barnett, one of the study’s lead authors.

California’s drought is just four years old. But the drop in the state’s hydroelectric production has been precipitous. Hydroelectric sources are projected to contribute just 7 percent of the state’s power this year, down from 23 percent in 2011.

While natural gas use has gone up during that period, renewable energy sources such as solar and wind have mostly filled the hydropower gap. California officials think the state can avoid power interruptions during peak hours and even meet long-term environmental goals despite hydropower’s decline.

But the hydroelectricity will be missed, said Robert B. Weisenmiller, chairman of the California Energy Commission. “It’s a great resource when we have it,” he said.

At Hoover Dam, the biggest worry is hitting “dead pool” status: The point at which the water level sinks too low to efficiently turn the dam’s massive turbines.

For years, engineers thought that Lake Mead would be “dead” when the waterline slumped to 1,050 feet above sea level. The turbines would spin roughly, rattling the dam’s base. Power generation would need to stop. And a structure hailed as an engineering marvel — called the greatest dam in the world when it was finished in 1935 — would cease to perform one of its primary functions.

Inside Hoover Dam, manager Cook walked past a reminder of the trouble he faces: A sign posted on a bulletin board listing decades of Lake Mead elevations.

The trend was distinctly downward. In June 2014, the lake hit 1,081 feet, a record low. This summer the lake is projected to set another record, at 1,073 feet.

But dam workers no longer worry about hitting the 1,050-foot dead pool. In the mid-2000s, as the drought settled in, they began planning to install new turbines that could deal with slower-moving water. Fearing lower lake levels were part of a long-term trend, they wanted to engineer a way around the drought’s effects.

Cook recalled that when the drought eased off briefly in 2012, dam workers wondered whether they needed to install the new equipment. But thankfully, Cook said, the first of the five new wide-head turbines was installed later that year.

Hoover Dam has 17 turbines split between powerhouses on the Arizona and Nevada sides of the canyon. Inside the Nevada powerhouse, the latest $3.5 million wide-head turbine is being installed. It’s the fourth of five and should be generating power later this year.

“It doesn’t look that different,” Cook said, standing near two men working on the turbine, “but it behaves different.”

The new turbines should allow the dam to continue generating power even if Lake Mead drops to 950 feet, Cook said. But a water level that low, he said, would be a sign of almost unimaginable environmental catastrophe, so the loss of hydroelectric power would be the least of anyone’s worries.

On that score, Cook is an optimist, however. He said he can imagine Lake Mead filling back up, if only briefly.

“It’ll just take a few years of really good rain,” he said.

This entry was posted on Monday, April 27th, 2015 at 8:07 am and is filed under Uncategorized.  You can follow any responses to this entry through the RSS 2.0 feed.  You can leave a response, or trackback from your own site. 

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About This Blog And Its Author
As the scarcity of water and energy continues to grow, the linkage between these two critical resources will become more defined and even more acute in the months ahead.  This blog is committed to analyzing and referencing articles, reports, and interviews that can help unlock the nascent, complex and expanding linkages between water and energy -- The Watergy Nexus -- and will endeavor to provide a central clearinghouse for insightful articles and comments for all to consider.

Educated at Yale University (Bachelor of Arts - History) and Harvard (Master in Public Policy - International Development), Monty Simus has held a lifelong interest in environmental and conservation issues, primarily as they relate to freshwater scarcity, renewable energy, and national park policy.  Working from a water-scarce base in Las Vegas with his wife and son, he is the founder of Water Politics, an organization dedicated to the identification and analysis of geopolitical water issues arising from the world’s growing and vast water deficits, and is also a co-founder of SmartMarkets, an eco-preneurial venture that applies web 2.0 technology and online social networking innovations to motivate energy & water conservation.  He previously worked for an independent power producer in Central Asia; co-authored an article appearing in the Summer 2010 issue of the Tulane Environmental Law Journal, titled: “The Water Ethic: The Inexorable Birth Of A Certain Alienable Right”; and authored an article appearing in the inaugural issue of Johns Hopkins University's Global Water Magazine in July 2010 titled: “H2Own: The Water Ethic and an Equitable Market for the Exchange of Individual Water Efficiency Credits.”