A comprehensive review of modern transmission expansion planning

Transmission Expansion Planning (TEP) has undergone a profound transformation over the past four decades, evolving from a deterministic, cost-driven task into a multi-dimensional optimization challenge that addresses uncertainty, renewable integration, resilience, and policy coordination. Early studies focused on meeting growing demand at minimum cost using fixed forecasts and static system assumptions. The rise of renewable energy, market deregulation, and grid digitalization has introduced new