Passive solar design takes advantage of the sun to heat and light a home, and natural wind ventilation for cooling, thereby making it more energy efficient. Through design strategies (building orientation, room orientation, and building shape), window sizes, shading, locations, and materials (heavy materials like concrete, brick, and stone in the path of the sun), passive solar strategies collect and distribute the sun’s energy naturally. Passive solar design does not typically require additional mechanical or electrical equipment.
A good resource for basic information on Passive Solar Design in homes can be found at the United States Department of Energy (DOE) Passive Solar website Passive Solar for Residential Buildings