Natural ventilation performance of classroom with solar chimney system

The considered Zero Energy Building is a three-story building located in Singapore which was recently retrofitted in 2009 with a range of green features. A solar chimney system was constructed to enhance the air ventilation within the interior spaces using a series of solar assisted ducts that linked the lower floor classrooms and upper floor hall. The mechanism of the solar chimney system is explained in detail and experiments conducted separated the classroom into experimental and reference regions of similar volumes. Results showed that the solar chimney system is operating well in the hot and humid tropics, including cooler days. Furthermore, the presence of the solar chimney system effectively caused the interior air speed of the experimental region to reach a maximum of 0.49 m/s and the interior air temperature to heat up slower and cool down faster by 1–2 h as compared to the reference region. Lastly, the position of the solar chimney's inlet within the classroom was found to be significant; lowering it to occupancy's height of 1.20 m increased the interior air speed to a maximum of 0.60 m/s.

► A solar chimney system linked the level 1 classroom and level 3 hall.
► Classroom experiments showed solar chimney operating well in hot and humid tropics.
► Maximum interior air speed of 0.49 m/s, with 1–2 h positive temperature lag.
► Lowering chimney's inlet to 1.2 m increased interior air speed to maximum of 0.60 m/s.