## 3 Results and Discussion
### Parametric Analysis  
A parametric study is applied to investigate the influences of decision parameters such as the turbine inlet pressure \((\mathrm{TIP})\), the generator temperature \((\mathrm{T_{gen}})\), the temperature differences at the Absorber \((\mathrm{\delta T_{ABS}})\) and condensers exit \((\mathrm{\delta T_{CON1}=T_{18}-T_{35}}\), \(\mathrm{\delta T_{CON2}=T_{16}-T_{37}})\) on the system performance prior to optimization. It is noteworthy to mention that, in parametric analysis for off-design conditions only one parameter, among the ones outlined in Table 1, is changed and the other parameters are calculated in off-design conditions. The ammonia concentration in the power section is kept constant as \(0.5\) kg\((\mathrm{NH_{3}})/\)kg\((\mathrm{solution})\).  
The variations of exergy efficiency as well as total exergy destruction rate with the turbine inlet pressure are shown in Figure 4a in off-design conditions. As shown, the exergy efficiency and \(\mathrm{\dot{E}_{D,tot}}\) take a local maximum and minimum values, respectively. The trends of these variations can be justified by representing the variation in power production, input exergy and loss exergy in some components with the TIP. Due to the reduction in reinjection geothermal temperature, the \(\mathrm{\dot{E}_{in}}\) is increased with an increase in TIP. In addition, changes in TIP has no effect on the produced heating capacity and the heating exergy of the system. On the other side, the power production is maximized locally at specific values of TIP. With an increase in TIP, the turbine mass flow rate decreases, however the turbine specific work has been optimized locally. As presented in the Figure 4b, the contrary effect of these parameters occurs in a way that leads to a local optimum for the produced net power output and the exergy efficiency. Furthermore, with an increase in TIP, the loss exergy rate in the ABS, REC, \(\mathrm{CON_{1}}\), \(\mathrm{CON_{2}}\) is increased. According to Equation (21), the total exergy destruction rate takes locally minimum values.  
The influence of the generator temperature on the exergy efficiency and total exergy destruction rate in off-design mode is presented in Figure 5a. It is seen that as the \(\mathrm{T_{gen}}\) increases, the exergy efficiency is locally maximized as well as the \(\mathrm{\dot{E}_{D,tot}}\) is increased. With an increase in \(\mathrm{T_{gen}}\), the \(\mathrm{\dot{E}_{in}}\) and \(\mathrm{\dot{W}_{net}}\) are decreased as shown in Figure 5b. The reduction rate of these two parameters occur in such a way that leads to a local maximum value for the exergy efficiency. The loss exergy which occurs in ABS, REC, \(\mathrm{CON_{1}}\), \(\mathrm{CON_{2}}\), is decreased by increasing \(\mathrm{T_{gen}}\). In this regard, according to Equation (21) the total exergy destruction rate decreases with an increase in \(\mathrm{T_{gen}}\).  
Figure 4: The effect of the TIP (**a**) on exergy efficiency and total exergy destruction rate (**b**) on the turbine specific work and mass flow rate.  
The influence of the temperature at the exit of the condensers on exergy efficiency and total exergy destruction rate in off-design mode is depicted in Figure 6. It is seen that with an increase in \(\delta\)T\({}_{\text{CON1}}\), the \(\eta_{\text{xergy}}\) and \(\dot{\text{E}}_{\text{D,tot}}\) are increased and decreased, respectively. In addition the \(\eta_{\text{xergy}}\) is decreased and \(\dot{\text{E}}_{\text{D,tot}}\) increased as the \(\delta\)T\({}_{\text{CON2}}\) changes. The net produced power is decreased with an increase in both \(\delta\)T\({}_{\text{CON1}}\) and \(\delta\)T\({}_{\text{CON2}}\). However, the input exergy to the system is kept constant in changing \(\delta\)T\({}_{\text{CON2}}\) and is decreased in variation \(\delta\)T\({}_{\text{CON1}}\).