Using a solar air heater to ventilate classrooms during the winter season in New Zealand: a potential alternative solution to assist during COVID 19 outbreaks

Ninety per cent of New Zealand classrooms are naturally ventilated by opening windows. Achieving a suitable ventilation level will rely on teachers. A survey showed that less than half of the teachers opened windows during teaching time. Due to the high occupant density in classrooms and a low natural ventilation rate, it is challenging to provide adequate ventilation during the southern hemisphere winter months (June to September). From 9 am to 3 pm, school hours align well with the optimum solar radiation, providing opportunities for solar ventilation.

Evaluation of vertical solar air collectors for natural ventilation using integrated and CFD models.

Vertical solar-air collectors that are used for providing natural ventilation can be a viable solution in buildings where higher ventilation rate requirements for better indoor air quality cannot be met by traditional natural ventilation methods. Indoor air quality problems have been experienced in Portuguese school buildings where a study revealed that the C02 concentrations in classrooms in winter were higher than the recommended health limits. To improve the environment in these classrooms, solar-induced ventilation has been suggested.