JUICE: Go With the Flow

By Published On: February 6, 2009

If you are a real blond, bronzed surfer in Southern California, you think of waves when you think of Santa Monica or Huntington Beach. If you’re board-less and pale, those coastal regions may make you think of once-through cooled power plants. If you’re among the latter, the electricity generating plants on those beaches and throughout the state have been creating waves—not the surfing kind. Calls to overhaul, replace, or close the state’s 19 once-through cooled power plants are moving front stage. Pressure is increasing at the state and federal levels to phase out generating units that use huge quantities of coastal water to cool down hot turbines. The outdated once-through technology consumes precious water and marine critters. Its outflow is warmer than surrounding water and can, according to the state, “scour” marine flora. The ultimate fate of the plants that are deemed needed to keep the grid humming will largely depend on which gets higher priority—water or power supplies. Case in point: a key strategy for protecting the coastal ecology and state electrical system reliability is to use reclaimed water in place of coastal water at some plants. “A nearly ideal situation would be one in which a wastewater treatment plant is located in very close proximity to a power generation facility and both facilities are owned or operated by the same municipality,” states the State Water Resource Control Board in its 2008 draft scoping policy on once-through cooling. The Los Angeles Department of Water & Power’s Scattergood power plant along the Santa Monica Bay and its neighbor, the Hyperion Wastewater Treatment Plant also owned by L.A., are said to fit the bill. But do they? Like surfing, it appears far easier than meets the eye. It entails riding multiple political, economic, and environmental currents and waves. They include the kind and amount of metal in the reclaimed water, which can be corrosive, impacts of a plant revamp on the surrounding neighborhood, the outcome of the U.S. Environmental Protection Agency’s revised rules for power plant intake structures, the State Water Board’s final once-through cooling policy, and the cost of upgrading the three Scattergood units. But the big Kahuna is what is deemed the best use of the treated wastewater from Los Angeles’ Hyperion treatment plant that sits next to the Scattergood facility. California, which swings between droughts and floods, looks like it is entering its third dry year—putting the squeeze on water supplies. There is not enough reclaimed wastewater to go around, said Jim Caldwell, LADWP environmental manager. Thus, the central question is what is “highest and best use for the Hyperion water?” he noted. Given crimped water supplies, higher priority for reclaimed water is using it as a substitute for potable water now used in industry and irrigation, as well as keeping salt water from intruding into coastal water supplies. Lower down on the list is power plant cooling. The large Hyperion treatment plant discharges about 420 million gallons of treated wastewater a day. That is close to the quantity of water Scattergood uses for cooling. The power plant pulls in 496 million gallons of coastal water a day, harming millions of fish and invertebrates, according to the State Water Board. Scattergood’s daily water use and aquatic impacts are dwarfed by the much larger Diablo Canyon and San Onofre nuclear power plants along the coast—each consuming about 2 billion gallons/day—but are still significant. Two of the three water-cooled units at Scattergood will be replaced with dry cooling, Caldwell said. In addition, a new unit will be built to more efficiently create megawatts from the digester gas generated by the wastewater treatment plant next door. Like the surfer however, the fate of the third unit will go with the flow, if there is any to go around. But to keep the water rolling for both those on and off the boards higher priority must be given to water and energy conservation that can be independently verified.

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