Flexibility Needs Assessment in the Distribution System with Significant Generation from Photovoltaic Power Plants

(PVPPs). The area is currently facing critical voltage limitations and network overload.

Forecasts indicate that investor demand for PV installations will continue to grow over the next five years. While positive from a sustainability perspective, grid limitations require revised technical connection conditions. Initially, the possibility of active demand management was considered, which would allow load shifting in accordance with the power generated by PV plants. However, in order to integrate all planned PVPPs, this option is not sufficient.

Additionally, this area lacks much of the necessary infrastructure to support advanced demandside management (DSM). Dynamic tariffing, which should enable the use of differentiated electricity prices, is in the process of being established. It has been shown that under current conditions, the installation of BESS (Battery Energy Storage Systems) represents a key solution to the problem of voltage limitations and network overload. In this way, production and consumption can be balanced, voltage stabilized, and the risk of network congestion reduced.

Although the investment requires higher initial capital, in the long term it ensures more stable network operation, safer integration of solar energy, and new sources of revenue. For investors in Bosnia and Herzegovina, monitoring regulatory changes and planning a flexible hybrid system is becoming a necessity. The possibility of connecting new PV plants is assessed in accordance with technical recommendations and the grid code. Through power flow calculations for selected operating modes, an assessment is conducted to determine which capacity of the photovoltaic system can be integrated without storage, and which requires storage of a certain power and capacity. Preliminary results indicate that for the planned integration PVPPs with a peak power of 10.6 MW, it is estimated that a BESS capacity of at least 14 MWh will be required to ensure stable operation and compliance with grid constraints.