ENERGY-EFFICIENT MEP SYSTEM DESIGN FOR MEGA INFRASTRUCTURE PROJECTS UNDER SAUDI VISION 2030
Saudi Arabia's mega infrastructure program is expanding the scale, complexity, and climatic exposure of buildings, transport hubs, healthcare cities, tourism districts, campuses, airports, and mixed-use developments. In these assets, mechanical, electrical, and plumbing systems are no longer secondary building services; they define operational carbon, lifecycle cost, indoor environmental quality, resilience, maintainability, and the ability of projects to meet Vision 2030 sustainability ambitions. This review paper synthesizes recent literature from 2020 to 2025 on energy-efficient MEP system design for large infrastructure projects in hot-arid and Gulf contexts. The study examines how high-performance HVAC, intelligent controls, BIM-enabled MEP coordination, efficient lighting, water-energy integration, renewable-ready electrical systems, commissioning, and digital twins can be combined into a lifecycle design framework. The aim is to develop a practical review-based model that links technical MEP decisions with Saudi Vision 2030 priorities, including energy efficiency, environmental stewardship, smart cities, local capability building, and resilient infrastructure delivery. The paper follows a structured literature review methodology covering peer-reviewed studies, energy standards, Saudi policy documents, and international reports. Findings show that the greatest performance gains are achieved when MEP design is treated as an integrated system rather than a collection of separate disciplines. Early-stage load reduction, climate-responsive HVAC selection, demand-controlled ventilation, high-efficiency chillers, smart lighting, heat recovery, greywater reuse, submetering, analytics-based operations, and continuous commissioning provide a coherent pathway for reducing energy intensity without compromising comfort or reliability. The review contributes a Vision 2030-aligned framework for mega project teams and identifies research gaps in climate-specific benchmarking, digital twin verification, water-energy optimization, and procurement models that reward lifecycle performance.