Optimizing Medium- and Low-Voltage Electrical Distribution Systems for Sustainable Infrastructure Development in Saudi Arabia

Medium- and low-voltage (MV/LV) networks are fundamental to reliable and affordable infrastructure in Saudi Arabia. Their design must simultaneously address demand growth, harsh ambient conditions, power quality, safe fault clearance and integration of new distributed energy resources. This structured narrative review examines engineering strategies for optimising distribution architecture, transformer deployment, cable sizing, voltage regulation, protection coordination and digital monitoring. Peer-reviewed and institutional evidence is interpreted alongside the Saudi Electrical Code (SBC 401), international electrical-installation standards and the objectives of Saudi Vision 2030. The review develops a decision framework in which lifecycle cost, technical losses, service continuity and regulatory compliance are evaluated together rather than sequentially. Distinctions are drawn between the MV supply system and LV installation, between design constraints and optimisation objectives, and between simulated performance and measured outcomes. An illustrative comparison demonstrates the type of trade-offs that can arise when capital expenditure is balanced against losses and resilience; its indices are hypothetical and not field measurements. The synthesis indicates that early load characterisation, scenario-based network modelling, selective redundancy, correctly coordinated protection and meter-supported commissioning can improve the quality of investment decisions. Benefits depend strongly on project topology, climatic exposure, operational discipline and verified local parameters. A staged implementation roadmap is proposed for Saudi airports, industrial estates, healthcare buildings and mixed-use developments.