The Western Area Power Administration (WAPA) will extricate itself from the California Independent System Operator (CAISO) at the end of this year, turning over its control area operations to the Sacramento Municipal Utility District under a proposal that still must be approved by Sacramento and the Western Electricity Coordinating Council. The power administration?s decision, announced July 13, apparently has more to do with control than with money. ?It?s a small difference? financially between CAISO and Sacramento, said Western spokesperson David Christy. He would not, however, divulge the amount of the difference because the agency has signed a nondisclosure agreement with the muni. Western has interest in interstate transmission lines from the Pacific Northwest as well as customers for its hydroelectric generation. WAPA clients, such as Redding, Roseville, and Irrigation District No. 1085, will receive their allocations from Western but will have to contract for the balance. This means that in wet years, customers will get their real-time generation, but in dry years they may not, added Christy. The power administration?s Central Valley Project supplies about 3,500 GWh for customers. Christy estimates that current customers will have to scramble for about 5,000 GWh of electricity. Smaller customers are expected to ask Western to buy on their behalf. Sacramento was selected because it met the agency?s criteria for flexibility, durability, certainty, operating transparency, and cost-effectiveness, according to Jim Keselburg, Western?s Sierra Nevada regional manager. ?It creates layers in operations,? lamented Stephanie McCorkle, spokesperson for the grid operator. While not venturing a scenario in which a lag time in communications among CAISO, Western, and the muni could affect grid-wide reliability, McCorkle said that the more control areas within the region, the less direct communications will be. The power administration?s change of control areas doesn?t necessarily require coordinating council approval, according to Kwin Peterson, WECC spokesperson. He said that if a new control area is formed or if there are significant changes to an existing control area, the coordinating council would have to recertify it for reliability. At this point, the significance of any change to the Sacramento control area is unknown, he added. WAPA had to decide between CAISO and Sacramento because its current contract with Pacific Gas & Electric expires at the end of the year. Sacramento must still approve the contract, which it is expected to do at its August 5 meeting.