**8. Conclusions**

The present study has been carried out for the optimization of hybrid renewable energy systems (HRES), where WT and PV function as generation systems and battery banks for storage as well as a backup system usingthe RBFNOEHO technique. Here, an existing hybrid system with both solar and wind generation combined and formed as 22 kV feeder and fed into the 110/22 kV Vagarai substation in the Palani Division in the Dindigul Circle of TANGEDCO in the State of Tamil Nadu of Indiahas been chosen for study purposes. The economic analysis of battery storage for the HRES system using the proposed hybrid technique is discussed. By utilizing the proposed hybrid technique, the load demand is predicted and the total cost of the system is minimized. Here, two case studies are analyzed. First, the cost is worked out for interruption periods without using energy storage and in the second, the cost is worked out using the proposed technique for the interruption periods with energy storage. According to the results, it is concluded that the hybrid systems including WT and PV with battery backup are less costly compared to the other systems.

**Author Contributions:** All authors contributed equally to the research activity to present as full article. **Funding:** This research was funded in part by EEEIC International, Poland.

**Conflicts of Interest:** The authors declare no conflict of interest.
