Implementing Storage Flexibility: Battery Storage and Photovoltaic Hybrid Systems’ Challenges and Opportunities in the Energy Transition

As global shares of variable generation from photovoltaic and wind increase, and mitigation of greenhouse emissions is approaching the decarbonization goals, the energy sector is facing flexibility challenges. Power system operators could impose grid limitations and curtailment measures in order to stabilize the grids and maintain the security of supply. In this paper, the feasibility of the hybrid photovoltaic power plant and battery energy storage system is analysed for the case of Bosnia and Herzegovina. Research assumes different grid limit scenarios for which battery sizing is determined, and for different battery installation type: on the powerplant’s inverter (direct current coupling), compared to the battery installation with a separate inverter ( alternating current coupling). The model allows for a detailed analysis of the proposed financial models, and for the improvements of the photovoltaic power plants' performances because of the operator’s limitations of electricity generation in the grids. The results indicate that with the direct installation, battery utilization is higher, and the project can be prepared before the photovoltaic power plant is installed, which would allow lower initial overhead costs. Conversely, for the existing power plants, alternating current coupling of the battery, installation, maintenance, and upgrading is easier, although there are higher costs because of the two inverters. The proposed research gives future investors a significant insight into the hybrid renewable storage systems modeling and proposes recommendations for its installation, given the possible grid operator’s constraints.