Operational Optimization of HVAC Performance in Hot–Humid Climate: Minute-Level Case Study of an Institutional Building in Bangkok, Thailand

Muhammad Fawad Saleem; Majid Baseer; Sardar Ahmed Imtiaz; Muhammad Fawaz; Sheyar Shoukat; Nauman Fayyaz

Authors

Muhammad Fawad Saleem Department of Mechanical Engineering, University of Engineering and Technology, Peshawar https://orcid.org/0009-0007-2369-0859
Majid Baseer Department of Engineering, University of Palermo, Italy
Sardar Ahmed Imtiaz Department of Mechanical Engineering, University of Engineering and Technology, Peshawar
Muhammad Fawaz Department of Mechanical Engineering, University of Engineering and Technology, Peshawar
Sheyar Shoukat Department of Mechanical Engineering, University of Engineering and Technology, Peshawar
Nauman Fayyaz Department of Mechanical Engineering, University of Engineering and Technology, Peshawar

Keywords:

HVAC Operational Performance, Cooling Load Profiling, High-Granularity Data, Data-driven optimization

Abstract

Operational efficiency is one of the fundamental factors that determine the energy performance of buildings in terms of their ability to maintain thermal comfort. This research aims to evaluate operational HVAC characteristics such as cooling loads, energy intensity, and thermal comfort in an institutional building in Bangkok, Thailand. The building has seven floors with 33 zones. This study utilizes minute-level electricity consumption and indoor environmental conditions to determine operational efficiency. The study found significant underutilization of operational HVAC systems in buildings. The load factor of the building is 26.0%, indicating that some parts of the building consume 4.5 times more energy than the zone with the lowest consumption. The thermal comfort of the building is only 60.6%, indicating that there is significant overcooling in buildings. The research has also found that there is no significant relationship between outside temperatures and energy consumption in buildings (R² = 0.023). The research has proposed several strategies that could potentially reduce peak demand by 12.8% while improving thermal comfort by 15%, without requiring any upgrades to HVAC equipment.

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