To provide an extremum-seeking control system for a chilled water plant including a feedback controller controlling at a condenser water temperature setpoint and an extremum-seeking controller optimizing a performance index.SOLUTION: At least one of a chilled water plant 1100, a chiller compressor 1102, a condenser water pump 1114, and a cooling tower fan 1136 are provided. An extremum-seeking controller 502 is configured to provide a condenser water temperature setpoint to a feedback controller. The extremum-seeking controller is configured to determine an optimal value for the setpoint condenser water temperature setpoint by perturbing the condenser water temperature setpoint with a stochastic excitation signal, monitoring a power consumption of equipment resulting from the perturbed condenser water temperature setpoint, estimating a gradient of the power consumption with respect to the condenser water temperature setpoint, and modulating the condenser water temperature setpoint to drive the estimated gradi
