*7.2. Case Study B*

In the case study B, the cost analysis for the interruption period using the proposed technique with energy storage has been analyzed. Here, the loss of the production of the green energy during grid interruptions and wind curtailment of the system are minimized because of the presence of battery storage using the proposed technique. Consequently, the proposed system gives lower cost with an optimal solution. The power flow in the HRES system using battery storage is analyzed forone day and one year. The variation of load per day and for a year is depicted in Figure 9.

**Figure 9.** Demand versus time profile of the proposed technique for (**a**) one day (**b**) one year.

Figure 9a the depicts how with the proposed technique the load demand is calculated during the time period of 24 h and Figure 9b illustrates the monthly load demand of the proposed technique. From Figure 9a, it is observed that the maximum hourly load demand of 5.9 MW is reached in the time intervals of 5 to 10 h. Likewise from Figure 9b, the maximum monthly load demand 1.39 × 10<sup>4</sup> KW is reached during the time period of 10 to 12 h.

The graphs of irradiance and wind speed for a 24 h. period are plotted in Figure 10. From Figure 10a, it is observed that the irradiance of the system is a maximum of 1000 <sup>W</sup>/m<sup>2</sup> during the time-period of 10 to 15 h. The maximum wind speed 12 m/s is predicted at the time moment of 5 to 15 h. in Figure 10b.

**Figure 10.** Analysis of (**a**) Irradiance (**b**) Wind Speed for one day.

Figure 11 shows the comparison analysis of power generated using energy storage, HOMER and the proposed technique for one day. Figure 11a depicts the graph of power versus time using the energy storage system. It is observed from Figure 11a, that by using the energy storage the maximum power 0.049 MW is generated in a period of 2 to 7 h. Figure 11b depicts the power generated using HOMER. By utilizing HOMER, the maximum power 0.047 MW is produced during the time interval of 20 to 25 h. Figure 11c shows the power generated using proposed technique. The maximum power generated using proposed technique is 0.05 MW at the time duration of 3 to 5 h.

Figure 12 shows the comparison analysis of power generated using energy storage, HOMER and proposed technique for one year. Figure 12a depicts agraph of power versus time using energy storage system. It is observed from the Figure 12a, which by using the energy storage the maximum power 1 MW is generated at the time period of 2 to 7 h. Figure 12b depicts the power generated using HOMER. By utilizing HOMER, the maximum power 1.3 MW is produced during the time interval of 2 to 4 h.

Figure 13 shows the individual generated power analysis using ESS, Without ESS, HOMER and Proposed for one day. Figure 13a shows the individual generated power using ESS. Figure 13a analyzes the PV, WT1, WT2 and WT3 generated power during the time period of 24 h. As seen from Figure 13a, the power generated by PV, WT1, WT2 and WT3 reaches the peak of 5.7 MW during the time instant of 5 to 10 h. Figure 13b shows the individual generated power without considering the ESS. From Figure 13b, it is observed that the power generated is in the maximum range of 5.75 MW at the time interval of 5 to 10 h. Figure 13c explains the individual generated power using HOMER. It is observed from the figure that the power generation is maximum 5.8 MW at the time duration of 5 to 10 h. Figure 13d delineates the individual generated power using the proposed technique. From Figure 13d, it is seen that the maximum power 5.9 MW is generated during the time interval of 5 to 10 h.

**Figure 13.** Individual Power analysis (**a**) With ESS (**b**) Without ESS (**c**) HOMER (**d**) Proposed technique for one day.

Figure 14 shows the individual generated power analysis using ESS, without ESS, HOMER and the proposed technique for one year. Figure 14a shows the individual generated power using ESS. Figure 14a analyzes the PV, WT1, WT2 and WT3 generated power during the time period of 24 h. As seen from Figure 14a, the power generated by PV, WT1, WT2 and WT3 reaches a peak of 160 MW during the time period of 6 to 8 h. Figure 14b shows the individual generated power without considering the BESS. From Figure 14b, it is observed that the power generated is in the maximum range of 155 MW during the time interval of 6 to 8 h. Figure 14c explains the individual generated power using HOMER. It is observed from the figure that the power generation is maximum 160 at the time periodof 6 to 8 h. Figure 14d delineates the individual generated power using proposed technique. From the Figure 14d, the maximum power 170 MW is generated during the time interval from 6 to 8 h.

**Figure 14.** Individual power analysis: (**a**) With ESS (**b**) Without ESS (**c**) HOMER (**d**) Proposed technique for one year.

Figure 15 shows the investigation of fitness graph for one day. It depicts the fitness comparison for one day. As seen from the figure, the base method solution converges after an iteration count of 32. The HOMER fitness solution converges at the 38th iteration and the proposed technique gives the solution faster than the other techniques.

**Figure 15.** Investigation of Fitness comparison for one day.

Figure 16 shows the investigation of cost for one day and one year. Figure 16a depicts the graph of cost versus time. The cost of the proposed technique is more optimal for one day than the other techniques such as without ESS, Base and HOMER. Figure 16b depicts the graph of cost versus time. The cost of the proposed technique is more optimal for one year than the other techniques such as without ESS, Base and HOMER.

**Figure 16.** Investigation of cost for (**a**) One day (**b**) One year.

Figure 17 shows the investigation of fitness graph for one year.

**Figure 17.** Investigation of Fitness comparison for one year.

As seen from the Figure 17, the base method solution converges after 49 iterations. The HOMER fitness solution converges at the 41s<sup>t</sup> iteration and the proposed technique gives the solution faster than the other techniques.
