Enhancing summer thermal comfort and energy performance in university office spaces using DesignBuilder’s parametric optimization: The role of window openings, solar shading, and HVAC systems

Year 2025, Volume: 10 Issue: 2, 461 - 510, 26.06.2025

Gonca Özer

https://doi.org/10.58559/ijes.1612536

Abstract

Improving energy efficiency, reducing consumption, and enhancing indoor thermal comfort are key concerns in sustainable architecture. While much research has addressed minimizing heating demands during winter, fewer studies have explored strategies to improve thermal comfort and reduce cooling loads during summer. This study aims to bridge that gap by analyzing the combined effects of window opening ratios, solar shading devices, and HVAC systems on summer energy performance and indoor comfort in faculty offices at Bingöl University.
The hypothesis suggests that optimizing window openings, implementing suitable shading strategies, and selecting effective HVAC systems can significantly enhance thermal comfort and lower cooling energy use. The study explores four main questions: (1) How effective is natural ventilation through varying window openings? (2) How much can solar shading reduce overheating and cooling loads? (3) How do mechanical systems interact with passive design strategies? (4) What is the combined effect of all three parameters on performance?
A parametric simulation approach was applied using DesignBuilder software. Scenarios included window openings from 5% to 50%, ten solar shading configurations, and five HVAC types. A total of 498 simulations generated a robust dataset for performance analysis. Results show that integrated optimization can reduce cooling energy use by up to 62% and improve thermal comfort by up to 54% compared to the base case. These findings confirm the initial hypothesis and underscore the value of holistic design strategies. In conclusion, this research offers a structured framework for improving summer thermal performance in educational office spaces. It provides actionable insights for architects, engineers, and policymakers seeking to enhance indoor environmental quality and energy efficiency in warm climate zones.

Keywords

BIM (Building Information Modeling) , BEM (Building Energy Modeling) , BES (Building Energy Simulation) , Building performance optimization , Natural ventilation and cooling energy in buildings , Building energy efficiency through sensitivity and pareto analysis

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