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arXiv · 2605.15431

Optimizing Chilled Water Systems with Cooling Towers via Virtual Power Metrics and Extremum-Seeking Control

Min Gyung Yu·Alex Vlachokostas·Karthik Devaprasad·Matt Cornachione·Stephanie Johnson·Tim A. Yoder·Timothy I. Salsbury
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Abstract

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.

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Min Gyung Yu, Alex Vlachokostas, Karthik Devaprasad, Matt Cornachione, Stephanie Johnson, Tim A. Yoder, Timothy I. Salsbury. 2026-05-14. Optimizing Chilled Water Systems with Cooling Towers via Virtual Power Metrics and Extremum-Seeking Control. https://doi.org/10.1080/19401493.2025.2575349

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