Integrating energy-efficient building practices with renewable energy systems enhances sustainability in remote communities. This study examines the impact of vernacular architecture and passive low-tech design on building energy consumption and the efficiency of PV-based hybrid microgrids. A parametric analysis using DesignBuilder evaluated twelve building scenarios that varied in construction materials, courtyard albedo, and orientation to determine the most energy-efficient configuration. Subsequently, HOMER software was employed to design and optimize a hybrid microgrid tailored to the optimal building design identified. The results demonstrate that integrating passive low-tech vernacular strategies led to a 25.6 % reduction in annual household energy consumption, decreasing from 5800 kWh to 4315 kWh. Based on the optimized building design, the hybrid microgrid required 28.45 % fewer photovoltaic panels (reduced from 232 to 166) and 77.93 % less battery storage capacity (from 145 kWh to 32 kWh), resulting in a 33.33 % decrease in the levelized cost of energy-from $0.195/kWh to $0.13/kWh. These results illustrate the synergistic benefits of combining passive design strategies with renewable energy systems, offering a replicable model for cost-effective, culturally contextual, and environmentally sustainable rural electrification in hot arid regions.