CHEOPS Hydropower Operations Model
Stanislaus River Operations Model and Improvement Evaluation
Pacific Gas & Electric (PG&E) Company (PG&E) and Tri-Dam Project each own and operate hydroelectric projects on the Stanislaus River system in northern California. These projects include Beardsley/Donnells, Sand Bar, Tulloch, Spring Gap-Stanislaus, Phoenix and Donnells-Curtis. With a combined capacity of 200 MW, the projects include 10 dams, four seasonal storage reservoirs, and six generating facilities spanning two river basins. Operation of the projects is highly interdependent due to reservoir storage and flow control restrictions in the basin. Tri-Dam Project and PG&E Company entered into an agreement for the coordinated operation of these projects with one goal of maximizing generation within regulatory and contractual constraints.
Conduct an operations and improvements study of the projects in the Stanislaus watershed. The intent of the study was to identify and evaluate any operational refinements or physical improvements that may be economical to implement either during the term of the current Federal Energy Regulatory Commission licenses or upon relicensing of the projects.
Devine Tarbell & Associates, Inc.’s (DTA) staff configured its CHEOPS™ model to analyze the river system. A cross-basin reservoir routing module was refined and configured for the specific hydrologic conditions present in the study system. DTA’s modeling staff used the CHEOPS™ model to perform an exhaustive analysis of the combined projects to identify an optimal coordinated operation of the system. Both seasonal storage operations and daily water schedules were scrutinized for potential increases in total generation and system benefits. Potential physical improvements to the system were also studied. The attractiveness of the alternatives was examined under existing license conditions and the electricity market in California, and under possible new license conditions and the electricity market that may exist in California once deregulation was complete. From initial data gathering to the final report and model training, the study effort was completed in five months.