Passive solar heating is a well established concept in cold climates, but passive systems which provide heating, cooling and ventilation depending on the season are less common. Some of the known systems in this category are: Sky-Therm, earth-air tunnel, the Silvestrini Bell, and the Barra–Costantini System, which are applicable in composite climates. Large areas of Central and Northern India have a composite climate, which includes hot-dry, hot-humid and cold climatic conditions. The present paper describes the development of a solar passive system, which can provide thermal comfort throughout the year in composite climates. In the first phase, passive model 1 comprising two sets of solar chimneys was developed and monitored for its performance for 1 complete calendar year. Based on the feedback and experience, an improved version of model 2 was developed. In model 2 both the trombe wall and sack cloth cooling concepts were incorporated, in order to make it more effective and also to give it a more compact and aesthetic appearance. Detailed system descriptions along with year-round performance data are given in this paper.