Courtesy of Western Water Magazine, an overview of the watergy nexus. As the article notes:
“…The connection between water and energy is more relevant than ever. After existing in separate realms for years, the maxim that it takes water to produce energy and energy to produce water has prompted a re-thinking of management strategies, including an emphasis on renewable energy use by water agencies.
Using groundwater has always been essential in the arid West. Now groundwater banking is be-ing promoted as the way to stabilize California’s water supply without the challenges associated with surface storage.
Across the West, investment in renewable energy projects like wind and solar is moving forward at an unprecedented rate as agencies face rising power costs and the need to trim budgets. The Metropolitan Water District of Southern California (MWD), the nation’s largest water supplier, is embarking on a slew of projects aimed at counteracting an expected five-fold increase in electricity costs to move water.
“As one of the larger energy users in the state, we have an obligation to pursue policies that are consistent with the district’s goals to balance long-term reliability and control costs, with the added benefit of reducing greenhouse gas emissions,” MWD Chairman Timothy Brick said after the district adopted its energy management policies Aug. 17.
In a noteworthy report in 2005, the California Energy Commission (CEC) said that “if not coordinated and properly managed on a statewide basis, water-related electricity demand could ultimately affect the reliability of the electric system during peak load periods when reserve margins are low.” The report concluded that “more efficient water usage, coupled with energy efficiency improvements in the water infrastructure itself, could reduce electricity demand in this sector.”
Since the report’s publication, experts have further scrutinized the energy needs associated with water and the potential for savings from water conservation and water efficient appliances.
MWD and other agencies are investing substantial resources in renewable energy projects to gain a degree of self-sufficiency and to reduce GHG. In MWD’s case, the move reflects the expiration of its Hoover Dam power contract in 2017 and the projected reduction in Colorado River hydropower supply. Producing and using power accounts for more than 25 percent of the district’s $870 million operations budget in 2010-2011.
Districts investing in solar and wind power take advantage of the fact that many have available land on which to build generation facilities. Wastewater agencies are incorporating on-site renewable generation (using mostly solar and biogas) as a means to offset their own electricity consumption, and in the case of biogas, sell it.
“We have the resources and a staff capable of installing and operating renewable power,” said Martha Davis, executive manager of policy development at the Inland Empire Utilities Agency. Inland Empire, which provides regional wastewater service and imported water deliveries to eight contracting agencies, has solar and wind projects and is pursuing a goal of being 100 percent powered by renewable energy by 2020. “We are at 50 percent now,” Davis said.
The nation’s largest municipal utility, the Los Angeles Department of Water and Power (LADWP) expects to have 20 percent of its power needs met by renewable energy by the end of the year. LADWP’s long-range power plan will address renewable its energy strategy and the LADWP energy efficiency program. “This process is all about getting feedback from our customers to help shape the city’s energy future,” said Aram Benyamin, senior assistant general manager for the department’s Power System.
Water agencies are finding that cutting energy costs makes good business sense. “I think they see rising energy costs as the big elephant in the room they have to address,” said Scott Hernandez, energy/climate change specialist with the Association of California Water Agencies (ACWA). To hedge against that inflation, more agencies are investing in renewable energy projects.
“Most water agencies tend to have both lands that are suitable for renewable energy, especially solar, and are in close proximity to transmission lines,” Hernandez said. “This allows agencies to maximize their production of renewable energy beyond their own needs and sell the excess back to the utilities for the broader public benefit.”
Reducing GHG emissions through better use of water helps the state meet the legislative mandate of bringing emissions to 1990 levels by 2020. “Water use requires significant amounts of energy,” says the scoping plan for AB 32, the landmark GHG emissions law enacted in 2006.
“Although state, federal and local water projects have allowed the state to grow and meet its water demands, greenhouse gas emissions can be reduced if we can move, treat and use water more efficiently.”
The push for a coordinated water and energy policy is tied closely with climate change adaptation; advocates of clean energy technologies say the pursuit of less harmful energy production benefits the West’s vulnerable water supply. According to a July report by Western Resource Advocates and the Environmental Defense Fund called Protecting the Lifeline of the West: How Climate and Clean Energy Policies Can Safeguard Water, power plants in Arizona, Colorado, New Mexico, Nevada and Utah consume enough water to meet the combined demands of Denver, Phoenix and Albuquerque.
“Western water utilities play an important role in reducing energy use and greenhouse gas emissions, by adopting robust conservation programs and avoiding energy-intensive new water supplies,” the report says. “Many western water utilities have already made demonstrable progress. In 2008 alone, conservation programs adopted by the Albuquerque Bernalillo County Water Utility Authority saved over 19 billion gallons of water and an estimated 138,000 megawatt-hours (MWh) of electricity.”
California agency personnel studying the issue say it is beyond question that more efficient use of water directly correlates to less energy used.
“When discussing potable supplies, it is still the case that the single best way to reduce the energy intensity in water is water conservation,” said Cindy Truelove, senior policy analyst for water issues with the California Public Utilities Commission (PUC). “One of the best ways to conserve water is to use every drop as many times as we can.”
The PUC, which regulates privately owned electric, natural gas, and water utilities, recently concluded “there is sufficient basis for determining that the amount of energy used by the supply and conveyance segment of the water use cycle is likely higher than the amount originally estimated by the Energy Commission in 2005. The primary source of the difference is likely attributable to groundwater energy.”
Experts say if the energy-water nexus is to be balanced, water must be optimally managed with carbon emissions.
“There will be a significant need for more water to provide energy for the 9 billion people who will be on the planet in 2050,” said Jan Dell, vice president of the energy division at CH2M HILL in Santa Ana. “Increasingly, water availability is becoming a critical factor in energy production operations and development plans and is anticipated to influence long-term profitability in the energy sector.”
The last few years have seen several high-profile meetings in which experts on water and power have shared knowledge in an effort to bridge the gap between the two resources. At a March 2010 meeting in San Francisco organized by the Carpe Diem Western Water and Climate Change Project, participants noted the existing discrepancy between the water and energy sectors.
“The energy efficiency world has had two decades to develop both technically and politically and is far ahead of the water-efficiency community,” a summary of the proceedings says. “There are not enough people working on water-energy issues from the water perspective, either in science or in policy.”
In July, the Water Research Foundation sponsored the first Water and Energy Sustainability Summit in Los Angeles to talk about solutions to avoid a statewide water-energy crisis.
“It’s a critical issue,” said Robert C. Renner, executive director of the Foundation. “The more water we use, the more energy is required. It’s a symbiotic relationship. But finite supplies of water and energy, greenhouse gas emissions and economic consequences drive the need to determine how to balance the water-energy relationship to avoid a future crisis.”
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