JUICE: The Water-Energy Knot

By Published On: February 13, 2014

Water and energy are like roses and chocolate. Not only are they inextricably linked but the coupling takes center stage at certain times: the latter when love spills over on Valentine’s Day and the former during dry spells. To save both energy and water, state leaders launched efforts to partner utility energy efficiency programs with water efficiency programs. Gov. Jerry Brown proposes a marriage made in heaven—or the market. He wants to direct $40 million of carbon cap-and-trade program auction revenue toward combined water-energy efficiency work in the coming year. This week, the California Public Utilities Commission announced yet another effort to tie the efficiency knot for the two critical resources. The administrative law judge, who considers water and energy “yin and yang,” may direct electric programs and gas utilities to support water efficient toilets and other fixtures and appliances. On top of that, President Barack Obama is expected to visit California today to see the drought’s heart break first hand in Fresno. Obama was expected to announce federal funding to help California grapple with the dowry-less drought, potentially including money for farmers to upgrade their irrigation systems. Agriculture is the largest consumptive user of water supplies in the state. Meanwhile, Senators in the nation’s capital introduced a bill to establish a panel to study the water-energy nexus and advise federal agencies how to use both resources more efficiently. Combining water and energy savings comes against the climate change backdrop—driven largely by burning fossil fuel, which may permanently dry out the state and much of the West. That means using less energy from fossil fuels and also becoming more efficient in the use of our constrained water supplies. Almost one fifth of the state’s electricity is consumed transporting and treating water supplies, according to the California Energy Commission. Moving it around alone consumes 6.6 percent. That’s a whole lot of flower power. Just talk to Metropolitan Water District, which spends about $280 million a year on power to pump water over the mountains that surround the Southern California metro area. Given the huge expenditures on energy to supply and treat water, which are passed on to consumers, it’s no wonder state officials want to find ways to wed energy and water savings. Saving water saves energy. Natural Resources Defense Council scientist Steve Fleischle points out that just getting an Energy Star washing machine in a home can save almost 3,400 gallons of water annually, plus enough electricity to power a home for nine days. That’s a monetary savings of $60 a year. However, like love, the water-energy relation is complex. Figuring out the savings of each resource is loaded because the two are governed by different laws, agencies, agendas and stakeholders. The direct and indirect impacts of shortages of the two resources are multifaceted. To help it sort through the water-energy thicket, the CPUC hired Navigant Consulting. As Navigant begins to study measures to conserve both resources, the line between the two may not be as direct as imagined. For instance, saving water in homes may not equate to pumping less surface water up and over mountains. Instead of coming out of home taps, water suppliers may use the surface water to fill up storage reservoirs—above and below ground—to build up supply cushions for inevitable dry years. Supplies in hydropower reservoirs may also be augmented, particularly during droughts. Low hydro means less hydropower supplies, and also curbs in hydropower load following. The Metropolitan Water District has used imports to increase its storage. That puts Southern California in a better position in this third year of drought than much of Northern California, even though the region has had only an inch or two of rain this “wet” season. MWD has developed the ability to store some 5 million acre-feet of water, enough to meet its total needs for almost three years. Currently, said MWD spokesperson Bob Muir, the storage facilities are about half full, meaning MWD is likely to take more surface water imports even if its customers conserve. So much for energy savings by moving less water over the mountains. But, there would still be downstream savings at wastewater treatment plants and perhaps savings related to heating water. For MWD and other suppliers, saving energy—while attractive—is not the primary concern. Instead it’s making sure they can supply water in a land that’s cyclically water stressed and prone to periodic droughts. There are other conundrums too, when it comes to saving both energy and surface water use. When supplies from rivers and other fresh water bodies are low, farmers and others make up the missing flow by pumping groundwater, an energy intensive operation. For a major irrigation supplier in the San Joaquin Valley, for example, its costs are expected to soar because of the drought and loss of state surface water supplies. Irrigators in the Semitropic Water Storage District in Kern County likely will get 100 percent of their supplies—about 400,000 acre feet—from groundwater. The electricity tab alone is estimated to be about $40 million, said Wilmar Boschman, Semitropic consultant and former general manager. High rates of groundwater pumping causes land in certain areas to sink. Land in parts of Kern County has seriously subsided, which in turn shrinks groundwater storage capacity. Other impacts of reduced water supplies to save energy include: * Savings from efficiency measures including permanently changing landscaping, appliances, and fixtures may eventually pay off in saving energy and water upstream as a permanent reduction in water demand factors into long-term planning. * It’s not just saving water that matters, but where the water you’re saving comes from. For instance, in the long run recycling more water in cities can save energy compared to pumping it long distances because once a sewage treatment plant—which has to run anyway—finishes its work, it takes less energy to finish treating that water to drinkable standards than it does to pump water over mountains. In some cases the situation may be the same for treating brackish groundwater. * Desalination of ocean water on the other hand likely takes more energy than pumping water. The City of Santa Barbara, which built a plant to make seawater potable in the 1990s but never used it, could restart the plant. San Diego will be getting desalinated water from a project Poseidon is building in Carlsbad. Poseidon is pursuing permits to build another desalination plant in Huntington Beach. Los Angeles has not discarded the possibility of building a plant. These are among the ‘for better or worse’ issues that the CPUC and other state agencies must sort out before making any wholesale turn toward using energy utility efficiency money to fund water efficiency measures. Meanwhile, the state should think roses and chocolate as it strives to tie the water and energy love birds’ knot.

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