Lithuania's electricity system has undergone a major structural transition with important consequences for cybersecurity. On 9 February 2025, Lithuania, Latvia and Estonia synchronised their electricity systems with the Continental Europe Synchronous Area, ending the Baltic states' long-standing synchronous operation with the IPS/UPS system controlled from Russia and Belarus [Litgrid, 2025; ENTSO-E, 2025]. At the same time, the continuing digitalisation of transmission and distribution networks, deployment of intelligent metering and distributed energy resources, and increasing dependence on information and communication technologies expand the cyber-physical attack surface of the electricity sector [ENISA, 2012; ENISA, 2016]. This review examines the cybersecurity challenges of Lithuania's smart-grid environment and develops an integrated framework based on asset visibility, IT/OT segmentation, identity and access management, secure remote maintenance, supply-chain security, continuous monitoring, incident response, resilience engineering, and regulatory alignment. Particular attention is given to the interaction between operational technology (OT), SCADA and protection systems; smart meters and Internet-of-Things devices; distributed energy resources; communications; third-party service providers; and cross-border electricity interconnections. The analysis also considers the implications of the EU NIS2 framework and the evolving European energy-sector cybersecurity architecture. The paper proposes a Lithuania-focused maturity model and a set of measurable indicators that can support transmission and distribution system operators, regulators, energy companies, and public authorities. The central finding is that smart-grid cybersecurity should be treated as a continuous resilience function rather than as a conventional information-security perimeter. Lithuania's post-synchronisation environment makes secure interoperability, coordinated incident response, supply-chain assurance, and recovery capability particularly important.
Keywords:Lithuania; smart grid; cybersecurity; operational technology; SCADA; electricity grid; NIS2; critical infrastructure; cyber resilience