Does higher embodied energy lead to lower operational energy? Insights from residential buildings in Ecuador's Costa Region

Over the past four decades, the residential sector worldwide has undergone significant transformations in terms of morphology, construction materials, and regulatory frameworks. These changes, driven by societal and technological developments, have had an impact on both operational and embodied energy. However, in warm-humid climates, where cooling demands are high, the implications of these energy aspects remain insufficiently explored. This study examines the evolution of this impact across 40 years, divided into four ten-year periods, using 54 representative residential buildings in Ecuador´s Costa region. Embodied energy was calculated based on bills of materials and fieldwork, while operational energy was calculated for domestic hot water and cooking, and simulated for lighting, electrical appliances and cooling. Both types of energy were then analyzed individually and compared over a 50-year lifespan. The findings reveal a progressive increase in specific total embodied energy, ranging from 11% and 21% across periods, and a 164% rise over 40 years. In contrast, specific total operational energy shows minimal variation between periods, although significant variability exists among individual samples, driven by morphological and material factors that operate independently of the period analyzed. Over a 50-years lifespan, embodied energy accounts for 23% (period 1) to 37% (period 4) of the operational energy for cooling. Notably, the increase in embodied energy has not resulted in reduced operational energy, a trend differing from other regions globally. This study highlights the importance of the relationship between embodied and operational energy throughout a building’s lifecycle, particularly in climates with high cooling demands. • Fifty-four single-family buildings were analyzed on Ecuador’s coast over 40 years. • Embodied energy has increased significantly in the las four decades (162%) • Operational Energy has a slight increase (5%) • Total Floor Area and Exposed Envelope Index area the most influential parameters.