## 5 Result of Simulation
### Profit Estimation and Comparison  
Table 5 is a rough estimate of the system construction costs based on the statistics of the data from various manufacturers [19]. \(C_{t}^{SB}\), \(C_{t}^{SBOS}\), and \(C_{t}^{PE}\) represent the cost of the storage block (SB), storage-balance of system (SBOS), and power equipment (PE), while \(P_{r}\) and \(E_{r}\) stand for the rated power and battery energy, and finally, \(C_{t}^{BESS}\) refers to the cost of the entire BESS. This study calculated the profit earned until EOL in each situation, and the related formulas are shown in Equations (11) and (12). To simplify the calculation, there were some simple assumptions in this paper:  
\[R_{t}^{EOL}=\sum_{m=1}^{m_{EOL}}\sum_{d=1}^{d_{m}}\sum_{h=1}^{24}\Bigl{(}p_{ cap}(m,d,\ h)+p_{eff}(m,d,\ h)\Bigr{)}\times q(m,d,\ h) \tag{11}\] \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Scenario** & **Mode** & **Spec. (\(P_{r}\)/\(E_{r}\))** & **SOC Level** & \(m_{EOL}\)**(Month)** \\ \hline
1 & dReg0.5 & 5 MW/6.25 MWh & 70\% & 189 \\
2 & dReg0.5 & 5 MW/6.25 MWh & 50\% & 210 \\
3 & dReg0.5 & 5 MW/6.25 MWh & 30\% & 228 \\
4 & dReg0.5 & 5 MW/3.125 MWh & 50\% & 195 \\
5 & dReg0.25 & 5 MW/6.25 MWh & 50\% & 189 \\
6 & dReg0.25 & 5 MW/3.125 MWh & 50\% & 165 \\
7 & sReg & 5 MW/6.25 MWh & 90\% & 159 \\
8 & sReg & 5 MW/12.5 MWh & 90\% & 162 \\
9 & sReg & 5 MW/6.25 MWh & 70\% & 180 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Battery life overview for each scenario. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Scenario** & \(P_{r}\) & \(E_{r}\) & \(C_{t}^{SB}\) & \(C_{t}^{SBOS}\) & \(C_{t}^{PE}\) & \(C_{t}^{BESS}\) \\  & **(MW)** & **(MWh)** & **(Thousand NTD)** & **(Thousand NTD)** & **(Thousand NTD)** & **(Thousand NTD)** \\ \hline
1 & 5 & 6.25 & 31,850 & 7350 & 11,900 & 51,100 \\
2 & 5 & 6.25 & 31,850 & 7350 & 11,900 & 51,100 \\
3 & 5 & 6.25 & 31,850 & 7350 & 11,900 & 51,100 \\
4 & 5 & 3.125 & 15,925 & 3675 & 11,900 & 31,500 \\
5 & 5 & 6\[R_{net}^{EOL}=R_{t}^{EOL}-C_{t}^{ESS} \tag{12}\] \[q(m,d,\ h)=1\ \{m,d,\ h\ |1\leq m\leq m_{EOL},\ 1\leq d\leq d_{m},\ 1\leq h \leq 24\} \tag{13}\]  
where \(R_{t}^{EOL}\) and \(R_{net}^{EOL}\) represent the total revenue and net profit estimated until the battery's EOL; \(m_{EOL}\) represents the number of months until the battery reaches its EOL. \(p_{cap}\), \(p_{eff}\), and \(q\) represent the capacity offer price described in Table 1, the efficiency offer price varying with the market bidding price every day, and the quality factor of operation, respectively. A.  dReg0.5 with the same rated capacity and battery energy but different SOC level target:  
As shown in Figure 22, Scenario 3 had the highest net profit among the three. The BESS specifications of the three Scenarios were the same so that the construction cost was also the same. Scenario 3 had the longest battery life and could thus earn the most profit. B.  dReg with the same rated capacity but different battery energy:  
As shown in Figure 23, either under the dReg0.5 or dReg0.25 mode, those with a higher C-rate had a higher net profit in the simulation results of this study. Although the battery life of those with a higher C-rate was shorter, the construction cost of their BESS was lower. Therefore, the net profit was still higher than that of those with a lower C-rate. However, these results are only the conclusion from the simulated data in this study; thus, the real results may vary due to the actual construction cost of actual sites and many other factors. Figure 23: Net profit under different C-rates using dReg0.5 and dReg0.25. Figure 22: Net profit under different SOC levels (dReg0.5). dReg0.5 and dReg0.25 with the same rated capacity and battery energy:  
As shown in Figure 24, the net profit difference between Scenario 2 and Scenario 5 was small. The two scenarios had the same specifications of BESS, so the construction cost was similar, but dReg0.5 (Scenario 2) had a slightly longer life.