Solar passive heating through a thermosyphon air panel

Thermosyphon air panels installed on the south wall of a building are being used for solar space heating in the cold desert climates of North India. This paper presents a simulation model to predict the performance of such panels; a numerical evaluation of the performance has been made, using the meteorological data for January (having maximum and minimum temperatures equal to −2·°C and −14·2°C, respectively, and an insolation of 4·58 kWh/m 2 day on the horizontal surface). For typical weather condition in January a 1·62 m 2 thermosyphon air panel is seen to collect about 2·3 kWh of energy per day with a rise of temperature of about 2·5°C to 13·5°C (with room air at 18°C as inlet air) and a working efficiency of approximately 32·5 per cent.