## 6 Sensitivity Analysis
The cost of the production increases because of initial investments, which is incorporated in calculating the global weighted average LCOE of utility scale solar system i.e., 0.195 $/kWh. It is estimated that the global average LCOE of utility scale solar PV has fallen by half in four years from 2010-2014. The most competitive utility scale system is generating electricity for just 0.08 $/kWh without financial support and even up to 0.06 $/kWh if low-cost finance is provided [54]. It is also estimated that the solar system will reach grid parity from year 2031 to 2042, when solar electricity costs will equal those of conventional electricity. The grid parity can be achieved faster under favourable conditions depending upon the government policies (to subsidies, low interest rates against loans for PV, maximize carbon tax etc. ), region (high solar resources), and less discount rate [51]. A trade-off policy can be developed for sustainably aware manufacturers and customers with less economic loss and high environmental benefits to select sustainable energy and sustainable products for cleaner production. These results will ensure that decision makers develop policies for adopting the solar renewable energy for the betterment of future generations to avoid global warming. Further tests are also necessary to check the sensitivity of the proposed model on the basis of costs related to the energy, carbon emission and other basic costs of production. Cost of carbon emission and LCOE for solar system is changing with respect to the region and government policies. Other factors like inflation, degradation rate, discount rate and efficiency of the system may also be influencing the \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Case** & **Goal** & **Result** & **Change \%** \\ \hline \multirow{3}{*}{1} & Total cost of production (\$) & \(11324\) & \(-0.1\) \\  & Carbon emissions (kg) & \(1753.60\) & \(10.6\) \\  & Total energy cost (\$) & \(162.09\) & \(-16.7\) \\ \hline \multirow{3}{*}{2} & Total cost of production (\$) & \(11329\) & \(-0.04\) \\  & Carbon emissions (kg) & \(1671.9\) & \(5.1\) \\  & Total energy cost (\$) & \(178.3\) & \(-8.33\) \\ \hline \multirow{3}{*}{3 (This) (paper)} & Total cost of production (\$) & \(11333\) & Initial \\  & Carbon emissions (kg) & \(1585.67\) & values \\ \cline{1-1}  & Total energy cost (\$) & \(194.51\) & \\ \hline \multirow{3}{*}{4} & Total cost of production (\$) & \(11338\) & \(0.04\) \\  & Carbon emissions (kg) & \(1508.6\) & \(-5.1\) \\ \cline{1-1}  & Total energy cost (\$) & \(210.72\) & \(8.33\) \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Percent change observed in the objectives of the model with variations of solar energy utilization. total cost of production and carbon emissions over the life cycle. To deal with these scenarios, Cases 5 to 10 are recommended for analysis for the sensitivity of the model, which are given in Table 13.  
1. In Case 5, by changing the LCOE of the solar energy from \(-50\%\) to \(+50\%\), the results exhibit an inverse relation, showing a slight change from \(+0.1\%\) and \(-0.1\%\) in the total cost (\(TC\)). However, a huge change of \(+14\%\) and \(-14\%\) occurs in the total energy cost (\(TEC\)). The original value is at equilibrium, showing symmetric positive and negative effects on \(TC\) and \(TEC\). 2. In Case 6, a similar inverse relation is found for the electricity cost, but the difference is that it has a little more impact of \(\pm 0.20\%\) on \(TC\) and a huge impact of \(\pm 33\%\) on \(TEC\) as compared to Case 5. 3. Carbon tax in the form of carbon emissions cost affects \(TC\) by \(\pm 0.18\%\) and has no effect on \(TEC\) as shown in Case 7. 4. In Cases 8 and 9, the manufacturing cost and crashing cost are having small effects from \(-1.45\%\) to \(+1.39\%\) and \(-0.78\%\) to \(+0.68\%\), respectively, on \(TC\) by changing these costs from \(-50\%\) to \(+50\%\). 5. The holding costs are showing a small impact around \(\pm 1.40\%\) on \(TC\) and is independent of \(TEC\) as given in Case 10.