## 2 Case Study Location and Building Data
### Building Information: Outpatient Medical Center  
The medical center is a single-story building facing south, divided into 11 zones with 127.63 m\({}^{2}\) surface construction and a volume of 521.18 m\({}^{3}\). A detailed description of the building's dimensions is found in Figure 2. The medical center is mainly built from masonry stone with plaster on the exterior and interior sides, a cast concrete ceiling,  
Figure 1: Psychometric chart with the heat indices reported in the historical center of San Francisco de Campeche, Mexico for 2022.  
door and windows frames made from wood, and windows made of 3 mm clear glass (Table 1). The building is reconditioned to carry out medical consultations and specialized ophthalmological surgeries. It operates Monday to Friday from 9:00 a.m. to 1:00 p.m. and 5:00 p.m. to 9:00 p.m.; and Saturdays from 9:00 a.m. to 4:00 p.m. The facilities operate with five employees in the consulting and optical zones and six employees in the surgery zone. The medical center has an average flow of 60 to 80 monthly patients for the consultation zone and an additional 80 people who come to the operation zones. It is important to emphasize that the age of the building implies the absence of regulatory standards regarding energy saving during its construction. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \multirow{2}{*}{**Envelope**} & \multirow{2}{*}{ \begin{tabular}{c} **U-Value** \\ **(W/(m\({}^{2}\) K))** \\ \end{tabular}  } & \multirow{2}{*}{ \begin{tabular}{c} **Total Solar** \\ **Transmission** \\ **(\%)** \\ \end{tabular}  } & \multirow{2}{*}{ \begin{tabular}{c} **Light** \\ **Transmission** \\ **(\%)** \\ \end{tabular}  } & \multirow{2}{*}{**Materials**} & \multirow{2}{*}{ \begin{tabular}{c} **Width** \\ **(m)** \\ \end{tabular}  } & \multirow{2}{*}{ \begin{tabular}{c} **Thermal** \\ **Conductivity** \\ **(W/(m-K))** \\ \end{tabular}  } & \multirow{2}{*}{ \begin{tabular}{c} **Specific** \\ **(J/(kg-K))** \\ \end{tabular}  } & \multirow{2}{*}{ \begin{tabular}{c} **Density** \\ **(kg/m\({}^{3}\))** \\ \end{tabular}  } \\ \hline \multirow{4}{*}{\ \begin{tabular}{c} Outdoor \\ walls \\ \end{tabular}  } & \multirow{4}{*}{1.773} & \multirow{4}{*}{Na} & \multirow{4}{*}{Na} & \multirow{4}{*}{Na} & \multirow{4}{*}{ \begin{tabular}{c} Outdoor \\ gypsum plaster \\ Cast concrete \\ Concrete block \\ \end{tabular}  } & 0.01 & 0.4 & 780 & 1860 \\  & & & & & & &  
An energy audit was conducted to identify the electricity devices with significant demand and establish the building's energy consumption baseline. Audit data was collected on the number of devices and operating hours of lighting equipment, HVAC systems, office equipment, and specialized medical practice systems. For the present study, HVAC systems only cover air conditioning devices, as due to regional climatic characteristics, the heating requirement for thermal comfort is null [22]. The energy audit information was collected through surveys carried out on staff, installed equipment datasheets, and measurements. Electrical data was captured by an AEMC 3945-B PowerGrid analyzer; it is a class S device designed to measure power frequency, magnitude of supplied voltage, voltage unbalance, interruptions, and electrical rapid changes with 5% precision concerning the nominal voltage. The measurement period ranged from January to December 2022. Energy audit results are presented in Table 2, which describes the electrical loads between the 11 zones of the ambulatory medical center, such as the energy final use of electricity. According to the data collected, higher electrical energy consumption is associated with using air conditioning to cool the spaces that patients and staff frequent to a greater extent. These results are consistent with the literature, where it is reported that air conditioning equipment represents about 66% of electricity consumption in regions with hot-subhumid or similar climates [23].