This paper presents an extremum seeking control (ESC) method for cooling tower fans to minimize overall power consumption of a chilled water plant system. Simulation studies across different climate locations demonstrate energy savings of approximately 15% compared to conventional control during summer conditions. This paper also proposes a virtual power meter (VPM) to enable use of the strategy in systems that lack physical power meters. Validation tests for the VPMs against physical meters showed good accuracy with a correlation of 96.11% and a normalized error of 5.11%. Coupled with the VPM, the proposed ESC control solution can be implemented on systems using typically available sensor measurements without the need for additional instrumentation.
@article{arxiv.2605.15431,
title = {Optimizing Chilled Water Systems with Cooling Towers via Virtual Power Metrics and Extremum-Seeking Control},
author = {Min Gyung Yu and Alex Vlachokostas and Karthik Devaprasad and Matt Cornachione and Stephanie Johnson and Tim A. Yoder and Timothy I. Salsbury},
journal= {arXiv preprint arXiv:2605.15431},
year = {2026}
}