Abstract— Battery energy storage systems (BESSs) are considered one of the most developed energy storage system (ESS) technologies because they have different benefits for distribution networks like smoothening the output fluctuations, improving the power quality, peak load shifting, voltage support and delaying the distribution network upgrade. This work involves integrating a BESS into a 33 KV distribution network in Jordan. CYME software is used to assess the impact of BESS at Almanara PV power plant on the 33 KV medium voltage network. The voltage level, power losses, power factor (PF) and voltage step are chosen as performance indicators. For each of these indices, comparisons between the grid performance with and without the BESS are carried out. In addition, the payback period of the BESS is calculated. The obtained results reveal that BESS not only improves the voltage level – with an overall improvement of about 3.03% at both feeders – but also reduces the losses, with an overall reduction in losses of 4.68% at both feeders. BESS is found to decrease the PF with an average of 0.83 at both feeders, while the voltage step doesn’t exceed the limits set by the International Electrotechnical Commission (IEC). Additionally, the performed economic analysis unveils that the payback period is about 10.98 years.