In order to ensure reliability of electricity supply, stability of the work of the electricity system (EES), integration of diversified energy sources at both Lithuanian and Baltic level and integration of the Baltic States into the common European EES, it is necessary to have forces and modernised electricity sector. This requires updating and extending the EES transmission network. 110/10 kV Baltupis, 110/35/10 kV Jašiūnai, Kaunas E, 110/10 kV Lentvaris, 110/35/10 kV Reikyvos and 110/35/10 kV Šeštokai TP 110 kV distribution stations will contribute to the modernisation of the EES network. The modernisation of these divisions by installing new advanced accounting, monitoring and control systems and other technological equipment will ensure reliable electricity supply for both existing and new electricity users in Vilnius, Šalčininkai district, Kaunas m., Trakai district, Šiauliai m. and Lazdijai district. in municipalities, the possibility of operational management will be increased, the reliability and flexibility of the power plant interconnection schemes will be ensured, the environmental pollution effects (replacement of old plants with oil filled with SF6 gas) will be minimised and will contribute to the climate warming targets (two substations will be equipped with installations that do not emit environmentally polluting substances).