## 6 Simulation Results and Discussion
### Case 3: BESS versus PHES with TADP DRP
The reference cases are the ones without DRP consideration (case 1) and the cost implication of introducing different types of DRP for each ESS-type microgrid are duly analyzed in terms of percentage cost reduction. For the BESS-based microgrid, introducing CPP DRP results in a cost saving of 0.53% of the investment from US $ 1.38 \(\times\) 10\({}^{7}\) (without DRP) to 1.37 \(\times\) 10\({}^{7}\); this cost saving is as a result of 21.59% and 5.33% reduction in the PV and BESS component sizes, respectively. This is because CPP DRP decreased the load demand and consequentially, the BESS dependency during the peak demand periods. For the PHES-based microgrid, the introduction of CPP DRP results in 0.44% cost reduction from US $ 9.06 \(\times\) 10\({}^{6}\) to US $ 9.02 \(\times\) 10\({}^{6}\). The cost-benefit is because of the 5.8% and 0.14% capacity size reduction of WT and PHES, respectively, and an increase of 7.4% PV capacity. For the two cases, It should be noted that there is a decrease in the investment costs as the CPP DRP shifts the FDR to off-peak from the peak period of the system and ensure a more flattened load profile and prevent sub-optimal capacity sizing. The potential superiority of TADP DRP over CPP DRP for microgrid design for high renewable energy penetration can be seen in the cost-benefits illustrated in Table 7. The inclusion of the TADP DRP in the BESS-based system resulted in 7.2% cost saving in the total planning costs. The planning cost reduction is due to a decrease of 17.58% and 2.5% for BESS and WT respectively with a slight increase of 0.11% in PV component size. Similarly, this trend is noted for PHES-based system with a total cost reduction of 1.48% resulting from 3.98% and 8.69% decrease in PHES and WT capacities, \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline \multicolumn{6}{c}{**BESS-Based Microgrid**} & \multicolumn{3}{c}{**PHES-Based Microgrid**} \\ \hline \multirow{2}{*}{**DRP type**} & Case 1: & Case 2: & Case 3: & Case 1: & Case 2: & Case 3: \\  & without DRP & CPP DRP & TADP DRP & without DRP & CPP DRP & TADP DRP \\ \hline
**PV capacity (kW)** & 1422 & 1110 & 1424 & 1699 & 1826 & 1858 \\
**WT capacity (kW)** & 1919 & 2165 & 1871 & 1657 & 1561 & 1513 \\
**ESS capacity (kWh)** & 6798 & 6436 & 5603 & 7800 & 7789 & 7494 \\
**TPC (US $)** & 1.38 \(\times\) 10\({}^{7}\) & 1.37 \(\times\) 10\({}^{7}\) & 1.28 \(\times\) 10\({}^{7}\) & 9.06 \(\times\) 10\({}^{6}\) & 9.02 \(\times\) 10\({}^{6}\) & 8.93 \(\times\) 10\({}^{6}\) \\ \hline
**\% cost saving** & - & **0.53\%** & **7.20\%** & - & **0.44\%** & **1.48\%** \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Techno-economic analysis for each ESS type based on the DRP flexibility options. Figure 9: (a,b) shows the Pareto front plots comparison for BESS and PHES-based microgrid design respectively, based on the DRP flexibility options. respectively. However, this results in an increase PV capacity of about 9.36%. Figure 10 illustrates the role and impact of DRPs in minimizing the gap between total generated RES power and load demand profiles. The prospects of TADP DRP over CPP DRP to reduce the mismatch between the load and the RES generated power profiles has been vividly portrayed by significant optimum component size reduction and hence the TPC minimization to realize the techno-economic benefit of a microgrid. Therefore, for the two system and types of DRP investigated, it can be inferred that the application of TADP DRP is more investment-worthy compared to the CPP DRP. TADP DRP short-term flexibility option takes into account the varying generation profile of WT and PV from the forecasting results; thus, the reason for its robustness.