## 3 Results
### Operation Cost Savings  
Figure 10 shows the saving obtained during the initial and the final 2 weeks (second and third columns of Table 2) for each of the three weather conditions. We present three groups of comparisons as follows. In black, configuration A (see Section 2.2.1); B1 in red (see Section 2.2.2); [B2,C,D] in different degrees of blue (see Sections 2.2.3-2.2.5, respectively). We can also find a summary of the RL improvement against each method in Table 3.  
\begin{table}
\begin{tabular}{c c c} \hline
**Weather Condition** & **Initial Phase Days** & **Final Phase Days** \\ \hline dry & 210–224 & 714–728 \\ \hline rain & 196–210 & 588–602 \\ \hline storm & 224–238 & 476–490 \\ \hline \end{tabular}
\end{table}
Table 2: Comparison periods.  
Figure 9: Days on which the RL agent and the PIDs will be compared.  
In concrete, looking at Figure 10, it can be appreciated that the RL has the A configuration, the hardest one to overcome in every weather condition. On the opposite side, the  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Control Method** & **Dry** & **Rain** & **Storm** \\ \hline A & 126.29\% & 34.61\% & 235.6\% \\ B1 & 937.97\% & 17.50\% & 37.45\% \\ B2 & 64.38\% & 12.80\% & 33.64\% \\ C & 64.18\% & 12.76\% & 28.68\% \\ D & 64.32\% & 12.84\% & 28.77\% \\ \hline \hline \end{tabular}
\end{table}
Table 3: OC improvement percentage (\(\frac{final-initial}{initial}\times 100\)) of the RL agent against each control method from the initial to the final stage (14 days cumulation sum).  
Figure 10: Savings obtained using the RL agent (cumulated difference of Operation Costs).  
blue group are clearly overcome by the RL agent since the onset of each weather condition. Lastly, B1 configuration is in the middle.  
We will start the comparison with the A and B1 configurations on dry weather. Remarkably, this peaceful dry weather condition is the hardest one that the RL agent must face. Let us obtain some insights to identify why.  
In Figure 10, dry weather, the RL agent shows that the initial phase has a hard time when it tries to control the plant with low \(OC\), at least when compared to A and B1 configurations. However, notice that even though it behaves worse on weekdays, it is on weekends when the agent makes use of its flexible and adaptive behavior to improve the \(OC\). This is a recurrent fact, as we will see in Sections 3.2 and 3.3. In fact, on the initial phase, it ends with the 14 days overcoming the savings in all configurations except for A. Nevertheless, once the RL agent has had the opportunity to learn (in the final phase), it ends up positive after 2 weeks of dry condition against each configuration, even compared with the most conservative A configuration.  
Now, attending to Figure 10, for rainy and stormy weather conditions, the RL agent overcomes every PID configuration from the very first time. Once again, the flexible and adaptive behavior of the RL agent is noteworthy during these unmercful weather conditions.  
In order to gain more insight into the different behaviors and why the RL agent ends up saving that much, we will see in detail the two main variables of the process: \(S_{NH}\) and \(OC\).