Energy Performance of a Zero-energy House in Oman’s Diverse Climates

The building sector faces critical challenges in reducing energy consumption and operational emissions, spurring interest in zero-energy buildings (ZEB). Previous studies have shown that passive and active strategies improve building performance in hot climates, but little work has addressed Oman’s diverse conditions. This paper assessed the energy performance of an eco-friendly “EcoHaus” residence in Oman under three distinct climates: Muscat (hot-humid), Nizwa (hot-dry), and Salalah (warm-humid). A calibrated simulation of the building was used to evaluate its baseline performance and to test energy efficiency measures. Results indicated that although the EcoHaus incorporated several passive features, its HVAC system dominated energy use. Passive strategies alone were insufficient in extreme conditions, whereas active upgrades significantly enhanced efficiency. Optimized designs achieved 54–63% annual energy savings across the climates, converting the house into a net-positive energy building with surplus generation. A bioclimatic analysis further identified suitable passive cooling strategies per locale: high thermal mass and night ventilation in hot-dry regions and shading with natural ventilation in warm-humid areas. The findings provide climate-specific recommendations and demonstrate how an integrated passive–active approach can guide ZEB design in Oman and similar regions.