Optimal Sizing and Operation of Hybrid Renewable Energy System: A Techno-Economic Analysis of Residential Building Considering Seasonal Storage

Sizing and operational optimization are essential for a reliable and cost-effective hybrid renewable energy system (HRES). This study develops an optimization framework to improve the techno-economic performances of HRES, consisting of PV/WT generation and hydrogen/battery storage units. The operational problem is addressed by a long-duration operational (LDO) management strategy, with its operational variables adjustable by optimization algorithms to control discharge capacities under different periods. A residential building located in a temperate area is selected as a case study and is also virtually tested in a tropical climate zone to demonstrate the robustness of the optimization approach. The simulation results confirm the efficiency of the optimization approach as the selected solutions achieve 17.69% and 29.85% improvements in system operational efficiency with equivalent baseline investments. The LDO strategy shows its superiority in tropical locations with lower seasonal mismatches. Moreover, the combination of long-term hydrogen storage with short-term battery storage is necessary for seasonal storage or off-grid operation, that is, almost 100% renewable energy penetration. However, this is achieved with more than twofold costs due to the diminishing marginal benefit. Therefore, a nearly off-grid operation (90% SSR) can be a trade-off solution and save the most investment in energy storage units. The proposed optimization approach and its findings can support the application of HRES in zero-energy/carbon communities and microgrids.