## 4 Conclusions  
The total exergy destruction of each component in a system can be divided into endogenous and exogenous, and each can be avoidable and unavoidable, to determine, besides the avoidable part due to the destruction of exergy identified by the traditional exergy analysis, which part is due to the structure or the operating conditions for the component in question. Therefore, many opportunities for improvement focus on the avoidable endogenous/exogenous fraction, where it is considered whether the improvement of the system depends on the device itself or on the interaction with the other components of the WHR system using ORC. The traditional exergy analysis of an ORC-based waste WHR system was performed using working fluids such as pentane, hexane, and octane, and the thermal inefficiencies of the primary devices were observed. However, it was not possible to determine the proportion of inefficiencies, how they could be avoided, or to study how they affected the interactions among each of the components that composed the system using only traditional exergy analysis. In most components, the exergy destroyed was usually produced by the nature of the component itself, however, there were also opposite cases such as the case of Pump 2 and the evaporator where, in percentage terms, the exogenous exergy destroyed was 36.06% and 54.52%, most of it being unavoidable. Thus, the interaction between components also plays an important role in some components, that is, an improvement in the others will positively affect components such as Pump 2 and the evaporator, which translates into a lower exergy destroyed. On the basis of the operating conditions of the WHR systems on ORC-based, the results showed that pentane was the working fluid with the best results, with 28% of net power higher than octane. For the condensing temperature using octane, there was no significant influence on the net power. However, for pentane, a decrease in net power was observed as the condensing temperature increased, and the opposite behavior was presented with hexane. In addition, the pinch point temperature of \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Components** & \(E_{d}\) & \(E_{d\mathbf{k}}^{EN}\) & \(E_{d\mathbf{k}}^{EX}\) & \(E_{d\mathbf{k}}^{IN}\) & \(E_{d\mathbf{k}}^{AV}\) & \(E_{d\mathbf{k}}^{EN,UN}\) & \(E_{d\mathbf{k}}^{EX,UN}\) & \(E_{d\mathbf{k}}^{EN,AV}\) & \(E_{d\mathbf{k}}^{EX,AV}\) \\ \hline ITC 1 & 6.46 & 5.49 & 0.97 & 8.58 & \(-\)2.11 & 0.19 & 8.38 & 5.29 & \(-\)7.41 \\ Pump 1 & 0.263 & 0.11 & 0.15 & 0.27 & \(-\)0.01 & 0.30 & \(-\)0.03 & \(-\)0.19 & 0.18 \\ Turbine & 10.63 & 1.62 & 9.02 & 2.28 & 8.35 & 0.05 & 2.23 & 1.56 & 6.78 \\ Pump 2 & 0.423 & 0.27 & 0.15 & 0.07 & 0.35 & 0.01 & 0.06 & 0.25 & 0.09 \\ Evaporator & 58.07 & 40.44 & 17.62 & 38.92 & 19.14 & 5.86 & 33.05 & 34.57 & \(-\)15.43 \\ Regenerator & 48.02 & 38.92 & 9.10 & 23.42 & 24.59 & 10.36 & 13.06 & 28.56 & \(-\)3.96 \\ Condenser & 17.77 & 4.01 & 13.76 & 0.00 & 0.00 & 0.00 & 0.00 & 0.00 & 0.00 \\
**Total** & 141.65 & 90.87 & 50.78 & - & - & - & - & - & - \\ \% & 100.00 & 64.15 & 35.85 & - & - & - & - & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Disaggregation of exergy for system components. the evaporator rise implied a decrease in the thermal efficiency, with was a consequence of the higher irreversibilities presented in the evaporator heat exchanger. However, it was shown that the effect is less accentuated in the case of pentane, which maintained an exergetic overall efficiency above 32%, with an evaporator pinch point ranging from 92 to 98 \({}^{\circ}\)C.  
In addition, the effect of increased thermal efficiency, evaporation pressure on net energy production, overall energy conversion efficiency, and specific fuel consumption and exergy destruction were also investigated.