Electric chillers (EC) that are installed at District cooling (DC) plants are designed for charging thermal energy storage (TES) during off peak period.The stored chilled water in the TES is used to support the demand of chilled water during peak period.This is the case of EC at Universiti Teknologi PETRONAS (UTP) DC plant due to insufficient supply of chilled water (CW) from steam absorption chillers (SAC) and TES.At the same time, the EC were also operated during the day time to support the demand of CW during peak timeand this was not per design.This led to EC were being operated at partial load.This study is on partial load operations of EC at the plant during year 2016 and 2017 covering four EC, each with 325 RT capacity.The main function of the ECs was to charge the TES during off peak period.Cases arise EC were also operated during the day.This resulted to EC were not being operated at full load.They were operated at partial load.This study is to determine the part load performance of EC operated under these conditions.Historical data was used for the study.Findings indicate most of the time EC were operated at about 10 h during the day. © 2023, Institute of Technology PETRONAS Sdn Bhd.