A Comparative Techno-Economic Analysis of Passive and Active Energy Efficiency Strategies in Buildings Across Diverse Climatic Zones

Abstract

The global building sector stands as a critical nexus in the effort to mitigate climate change, accounting for over one-third of global energy consumption and a commensurate share of greenhouse gas emissions. This paper conducts a rigorous comparative analysis of two principal paradigms for improving building energy performance: passive design strategies, which leverage architectural form and materials to minimize energy demand, and active systems, which employ mechanical and electrical technologies to control indoor environments. Through a techno-economic evaluation of case studies in distinct hot-humid and cold-temperate climates, this research quantifies the energy savings and financial returns of specific technologies. The analysis reveals that passive measures, particularly building envelope enhancements like insulation and high-performance glazing, consistently offer superior cost-effectiveness, with Internal Rates of Return (IRR) often exceeding 35% in hot climates. In cold climates, a clear hierarchy of cost-effectiveness emerges, where measures like roof insulation provide the most favorable returns, and the viability of more invasive retrofits is tied to maintenance cycles. While active technologies such as Energy Recovery Ventilation (ERV) and Variable Air Volume (VAV) systems provide significant energy savings and enhanced control, their financial returns are generally lower than foundational passive investments. However, the study critically demonstrates that the economic viability of all measures is highly sensitive to external factors, including energy pricing policies and occupant behavior. The findings indicate a significant "performance gap" between simulated potential and real-world outcomes, driven by the complex interaction between occupants and building systems. Consequently, this paper argues for an integrated, "passive-first" design philosophy, where robust passive strategies are implemented to fundamentally reduce energy loads, which are then met by appropriately sized, highly efficient active systems. This hybrid approach represents the most resilient and cost-effective pathway to decarbonizing the built environment.