## 5 Results
### Exergy Analysis  
The influence of the pressure ratio on the overall exergy efficiency and the total exergy destruction is observed in Figure 3. The cycle operating with MgCl\({}_{2}\)-KCl salts presents higher exergy efficiency compared to solar salts across all pressure ratios (Figure 3a). The maximum overall exergy efficiency achieved is 23.96% for solar salts and 25.54% for MgCl\({}_{2}\)-KCl salts. As a result, the use of chloride salts improves the maximum overall exergy efficiency by 6.6%. The pressure ratio that maximizes the overall exergy efficiency aligns with the ratio that optimizes the system from an energy perspective. This pressure ratio also minimizes the exergy destruction (Figure 3b). The minimum exergy destruction is 31.48 MW for the solar salts and 28.94 MW for the MgCl\({}_{2}\)-KCl salts. The exergy destruction is reduced by 8.78% when working with chloride salts. Table 7 summarizes the exergy destructions of each component at the pressure ratio which minimizes the total exergy destruction. For both molten salts, the component with the highest exergy destruction is the solar system, with approximately 87% of the total exergy destruction. In the components of the power cycle, the highest exergy destruction occurs in the precooler for the system using solar salts, with 3.02%. For the system that utilizes MgCl\({}_{2}\)-KCl salts, the highest exergy destruction is found in the low-temperature recuperator, with 3.59%. As can be observed, the use of chloride salts increased the exergy destruction in the high and low-temperature recuperator. Exergy destruction in the mixing process is practically negligible. Figure 3: Impacts of pressure ratio (PR) on overall exergy efficiency and total exergy destruction. Figure 4 shows the influence of the pressure ratio on the exergy destruction of the solar block. As can be observed, the optimum ratio that minimizes this exergy destruction is the same that maximizes overall exergy destruction efficiency. Figure 5 illustrates the impact of the pressure ratio on exergy destruction for both high and low-temperature recuperators. The exergy destruction in both recuperators shows a similar trend with the two molten salts, decreasing as the pressure ratio increases. Notably, exergy destruction is higher for the chloride salts. For these salts, the minimum exergy destruction is 0.64 MW for the high-temperature recuperator and 0.86 MW for the low-temperature recuperator. In contrast, for the solar salts, the minimum exergy destruction is 0.34 MW for the high-temperature recuperator and 0.74 MW for the low-temperature recuperator. Consequently, the utilisation of MgCl\({}_{2}\)-KCl in the cycle results in an augmentation in minimum exergy destruction of 88.23% and 16.21% for the high and low-temperature recuperators, respectively. \begin{table}
\begin{tabular}{c c c} \hline
**Component** & **Solar Salt** & **MgCl\({}_{2}\)–KCl** \\ \hline Solar system & 27.38 MW & 25.10 MW \\ IHE & 0.26 MW & 0.12 MW \\ T & 0.75 MW & 0.51 MW \\ HTR & 0.69 MW & 0.93 MW \\ LTR & 0.89 MW & 1.04 MW \\ RC & 0.29 MW & 0.18 MW \\ MC & 0.27 MW & 0.20 MW \\ PC & 0.95 MW & 0.86 MW \\ M & \(\approx\)0 MW & \(\approx\)0 MW \\ \hline \end{tabular}
\end{table} 
Table 7: Exergy destruction for each component at minimum total exergy destruction conditions. Figure 4: Comparison of exergy destruction of the solar block at different pressure ratios. Figure 6 shows the energy destruction occurring in the intermediate heat exchanger (IHE) and the precooler (PC) at different pressure ratios. In both heat exchangers, the exergetic destruction is higher when the cycle operates using solar salts. For the IHE, the impact of the pressure ratio on exergy destruction is minimal. The lowest exergy destruction of 0.12 MW occurs at a pressure ratio of 3.075 when using MgCl\({}_{2}\)-KCl salts. For solar salts, the minimum exergy destruction on the precooler is 0.26 MW at a pressure ratio of 3.125. In contrast, the effect of the pressure ratio on the exergy destruction of the precooler is significant.