Techno-economic optimization of hybrid renewable systems: New battery sizing approach with growth optimizer

This paper presents a new model for designing an independent hybrid energy system incorporating photovoltaic panels, wind turbines, and a storage system while introducing a novel approach to minimize the levelized cost of electricity (LCOE) in hybrid photovoltaic-wind-battery (PV-WT-BT) microgrids by optimizing the battery's depth of discharge (DOD). The DOD of batteries, a key factor influencing their life cycle and overall longevity, is the primary optimization focus of this work. To ensure system reliability, the Loss of Power Supply Probability (LPSP) is incorporated into the optimization framework. The Growth Optimizer (GO) algorithm is employed to simultaneously optimize battery's DOD and determine the optimal sizing of PV, WT, and BT units. A case study demonstrates the effectiveness of this approach in reducing LCOE while maintaining reliability. Results highlight a significant reduction in LCOE by dynamically optimizing DOD alongside the component sizing rather than relying on fixed DOD. Optimizing the DOD reduces costs, with savings of 5.69 % for PV/WT/BT, 7.05 % for PV/BT, and 1.5 % for WT/BT compared to a fixed 80 % DOD. This method not only ensures reliable load demand fulfillment but also enhances the sustainability and economic efficiency of the microgrid.