Hourly Pumped‐Storage Modeling with Microcomputer

Abstract

A chronological approach to scheduling a pumped‐storage plant optimally using an hourly time step is discussed. An objective function defines total power cost for any hour as a function of system generation; the pumped‐storage plant adds cost for any pumping hour and reduces cost for any generating hour. Hourly conservative‐of‐flow equations, coupled with lower and upper limits on the plant's storage, constrain the reservoir's hourly storages. Unit pumping and generating capabilities are nonlinear functions of the plant's head and are included here as nonlinear upper bounds on hourly generation or pumping. An existing nonlinear programming package optimizes the objective function while satisfying the constraint equations. An application to a large pumped‐storage plant that is part of a large power system is given for a weekly planning period. This approach requires only a minimum programming effort, even for a problem with hundreds or thousands of constraint equations, and is implemented on an enhanced personal computer.