## 3 Materials and Methods
### Case Study Selection and Description  
The selected case study is located in Dhahran, a city in the Eastern Province of Saudi Arabia, positioned at a latitude of 26.27\({}^{\circ}\) and a longitude of 50.17\({}^{\circ}\). This area represents a major climatic zone characterized by hot, dry conditions, with elevated humidity levels during certain months [50]. The building under study is a typical student dormitory at King Fahd University of Petroleum and Minerals (KFUPM). Data on the building's characteristics were collected through on-site visits and from the Projects Department at KFUPM, which provided drawings, construction details, and material specifications. The dormitory spans three floors, with each floor covering an area of 1210.8 m\({}^{2}\) and a height of 2.9 m. The building has an L-shaped configuration, three staircases, and is oriented 17 degrees west of north. Each floor contains 29 bedrooms, with each room accommodating two students. Additionally, each floor features three bathroom zones, a lobby, a study room, and a mechanical room (Figure 2). The building is a precast concrete structure, which serves as the main construction material. The external walls are made up of 27 cm thick precast wall panels featuring 4 cm of expanded polystyrene (EPS) insulation, yielding a U-value of 0.563 W/m\({}^{2}\).K. The roof comprises a 20 cm hollow core concrete slab topped with phenolic rigid insulation, waterproofing, and concrete tiles, resulting in a total thickness of 35 cm and a U-value of 0.45 W/m\({}^{2}\).K. The windows are sliding rectangular units measuring 1.5 m by 1.2 m, with aluminum frames that lack thermal breaks. They feature double glazing with 6 mm thick glass, a bronze tint, and a 12 mm air gap, resulting in a glazing U-value of 2.66 W/m\({}^{2}\).K and a Solar Heat Gain Coefficient (SHGC) of 0.861. According to the architectural drawings, the windows are uniformly distributed, ensuring that each student room has one window; however, there is no solar protection provided. As indicated in the building elevations,  
Figure 1: Methodology framework. the total area of all facades is 2031.7 m\({}^{2}\), with the total window area measuring 201.8 m\({}^{2}\), resulting in a window-to-wall ratio of 9.9%. The HVAC system consists of a water-cooled chiller station that provides cooling for 21 residential buildings housing students, with an occupancy density of 0.045 persons/m\({}^{2}\). On-site visits were conducted to gather the necessary data for creating an accurate model of the building. Data was collected from energy meters installed at the chiller plant over the course of a year, including the chiller plant's electrical power and other loads (such as pumps and tower fans), which account for an additional 20% of the total energy consumption of the chiller plant. Table 1 presents the data obtained from the chiller meter screen. The chiller used is an electrically driven centrifugal YORK YX model with a nominal capacity of 2100 kW, a pump efficiency of 0.9, and a Coefficient of Performance (COP) of 5.5. The chiller is intricately connected to four cooling towers, which transport chilled water through a pipeline to the residential buildings. The system configuration is illustrated in Figure 3. The operational load of the water-cooled chiller is determined by the temperature difference between the inlet and outlet of the housing space. As the internal temperature approaches the desired thermal comfort level, the cooling load decreases, with the cooling setpoint established at 23 \({}^{\circ}\)C. However, in the examined case study, the chiller system operates continuously for an average of 16 h per day throughout the year due to the high external temperatures in the region.