## 3 Simulation Methodology
### Weather Conditions of the Four Regions Selected for This Study  
The ASHRAE 90.1-2009 international climate zone definition, which classifies world climate based on heating and cooling degree days, was used to classify climatic zones in this study [39]. Four regions, namely, Incheon: Seoul metropolitan area--South Korea, New Delhi--India, Berlin--Germany, and Minneapolis--U.S., were selected, and they show typical characteristics of each climatic zone. The weather files were obtained from the U.S. DOE weather data (2017) [20], and Table 5 and Figure 7 show the detailed values. Incheon belongs to the ASHRAE 4A Mixed-humid climatic zone, and its climate according to the Koppen climate classification is Dwa (cold and dry winter, and hot summer). The maximum average monthly temperature is 25.0 \({}^{\circ}\)C in August, and it has a hot and humid summer, with maximum average monthly relative humidity of 86.3% in July. The minimum average monthly temperature is \(-2.2\)\({}^{\circ}\)C in January, and it has a cold and dry winter, with minimum average monthly relative humidity of 46.5% in January. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \multirow{2}{*}{**Regions**} & \multirow{2}{*}{**ASHRAE Climate**} & \multirow{2}{*}{\begin{tabular}{c} **Koppen** \\ **Climate** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Latitude** \\ **Cimate** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Oudoor Air** \\ **Longitude** \\ **N(°)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Relative Humidity** \\ **(Average Monthly)** \\ **Min. Avg.** \\ **Max (°C)** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **HDD** \\ **Min. Avg.** \\ **Max (°C)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **CDD** \\ **(18 \({}^{\circ}\)C)** \\ \end{tabular} } \\ \hline Incheon & 4A & Dwa & 37.48 & 126.55 & \(-2.2/11.8/25.0\) & 46.5/68.8/86.3 & 2762 & 611 \\ \hline New Delhi & 2A & Aw & 26.62 & 77.20 & 14.1/24.7/33.2 & 63.1/73.5/86.6 & 286 & 3010 \\ \hline Berlin & 5A & Cfb & 52.52 & 13.39 & 0.3/9.8/19.1 & 38.4/62.5/74.6 & 3283 & 147 \\ \hline Minneapolis & 6A & Dfb & 46.97 & \(-93.26\) & \(-9.9/4.8/17.5\) & 49.7/67.3/77.2 & 4202 & 417 \\ \hline \end{tabular}
\end{table} 
Table 5: Detailed climate characteristics of the four regions. Figure 7: Selection of the four regions for the EnergyPlus simulation. Incheon has 2762 heating degree days (HDD, 18 \({}^{\circ}\)C), and 611 cooling degree days (CDD, 18 \({}^{\circ}\)C). New Delhi belongs to the ASHRAE 2A Hot-humid climatic zone, and its climate according to the Koppen climate classification is Aw (tropical and dry winter). This weather has 286 heating degree days (HDD, 18 \({}^{\circ}\)C), and 3010 cooling degree days (CDD, 18 \({}^{\circ}\)C). It is also very hot and humid, with a maximum average monthly temperature of 33.2 \({}^{\circ}\)C in June, and maximum average monthly relative humidity of 86.6% in August. Berlin belongs to the ASHRAE 5A Cool-humid climatic zone, and its climate according to the Koppen climate classification is Cfb (temperate and warm summer). It has 3283 heating degree days (HDD, 18 \({}^{\circ}\)C), and 147 cooling degree days (CDD, 18 \({}^{\circ}\)C). The maximum average monthly temperature is 19.1 \({}^{\circ}\)C in July. Its average maximum monthly relative humidity is 74.6% in December. Minneapolis belongs to ASHRAE 6A Cold-humid climatic zone, and its climate according to the Koppen climate classification is Dfb (cold winter and cool summer). It has the greatest number of HDD of all four regions in this study, with 4202 heating degree days (HDD, 18 \({}^{\circ}\)C), and 417 cooling degree days (CDD, 18 \({}^{\circ}\)C). Its maximum average monthly temperature (17.5 \({}^{\circ}\)C), minimum average monthly temperature (\(-\)9.9 \({}^{\circ}\)C), and average monthly temperature (4.8 \({}^{\circ}\)C) are the lowest among the four regions. Figure 8 compares the monthly outdoor temperature and relative humidity in the four regions.