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. The modernisation (reconstruction) of 110/35/10 kV Kazlu Rūda TP and 110/6 kV Vilkpėdė TP 110 kV will contribute to the renewal of the EES network. The modernisation of 110/35/10 kV Kazlu Rūda TP and 110/6 kV Vilkpėdė TP 110 kV by installing new advanced metering, monitoring and control systems and other technological equipment will ensure reliable electricity supply for both existing and new electricity users in Kazlu Rūda and Vilnius municipalities, increase the operational management capability, ensure the reliability and flexibility of electric interconnection schemes and minimise the impact of environmental pollution (the old plants filled with oil are replaced with new SF6 gas-filled installations).