*2.2. BES Modeling*

This study was conducted using TRNSYS 18, a BES modeling tool program as earlier stated. TRNSYS, which stands for "Transient System Simulation Program", is a versatile component-based program that provides tools for simulating both simple and complex energy flows in buildings. This program has been used for many different applications. Examples of simulations carried out using TRNSYS are those for energy systems research, energy building simulation, solar thermal processes, solar applications, ground-coupled heat transfer, geothermal heat pump systems, air-flow modeling, system calibration, hydrogen fuel cells, wind and Photovoltaic (PV) systems, and power plants [21].

The modeling process was completed in three parts, including, pre-processing, modeling, and simulation. The details of each are discussed below in the corresponding sub-sections. An overview of the complete modeling process is detailed in Figure 4.
