Do heatwaves affect students’ performance?

A new study has been published which assesses the performance of two groups of students during a heatwave; one group who had air-conditioning and one without. Several other studies detailed below, have also looked at the impact temperature increase has on student learner performance, the addition of this latest study has led to some interesting conclusions.

The studies

‘Heating and Learning’, a study published by the US National Bureau of Economic Research has proven that for every 0.55^oc increase in average temperature over the year there was a 1% fall in learning. As temperatures exceeded 21^oc, student performance noticeably dipped and as temperatures surpassed 32^oc, performance declined at an alarmingly fast rate.

The study ‘Daylighting and Productivity’, by Heschong Mahone Group, now TRC Companies, proves levels of daylight in schools’ impact student comfort and performance, also touches on the subject of thermal discomfort.

‘Direct sun penetration into classrooms, especially through unshaded east or south facing windows, is associated with negative student performance, likely causing both glare and thermal discomfort. Blinds or curtains allow teachers to control the intermittent sources of glare or visual distraction through their windows.  When teachers do not have control of their windows, student performance is negatively affected.’
– Heschong Mahone Group

And now, a third study has produced similar results proving that yes, increases in temperature do significantly affect productivity but that air conditioning is not a sustainable way to counteract the impact. Reduced cognitive function during a heat wave among residents of non-air-conditioned buildings: An observational study of young adults in the summer of 2016, released in July 2018 assessed students cognitive function when air conditioning was used compared to when it wasn’t.

Key findings:

• The study found that increases in temperature impacted all students, not just the more vulnerable.
• Adults in the US spend 90% of their time inside. This is the first study of its kind to assess the impact of heatwaves and temperature increases on cognitive function and productivity.
• The overarching message was that although air conditioning is a solution at present, it is not a sustainable one as it has been proven to be contributing to climate change.

Prevention is better than cure

Studies conducted by the BBSA have proven that blinds and shutters are a viable, passive alternative to energy hungry air conditioning use.  Due to temperature and light being dependent on the sun’s position, unshaded east-facing rooms will be warmer than west-facing and buildings will have ‘hot spots’, which change throughout the day. A single solution that manages a buildings entire temperature, is likely not going to be as effective as managing individual areas, such as is possible when using solar shading.

The solar control benefits are maximised with external blinds as this prevents solar gain in the first instance. Considering this solution at the design stage is crucial as the following quote shows.

‘Solar radiation is an important issue in all building projects as it has significant impact on the internal environment and affects the design of HVAC systems. Selection of solar shading should always be one of the first steps in the design of HVAC systems, as the demand for power and energy consumption are greatly influenced by solar shading. Shading makes it possible to prevent extra solar heat from entering the building and to remove this heat, which costs precious energy. In winter time, however, the free heat from the sun is very welcome to reduce the building’s heating cost’

Olli Seppänen
Former Secretary General
Chair of the Technology and Research Committee (TRC)

REHVA
(Federation of European Heating, Ventilation and Air Conditioning Associations)

Resources

Heating and Learning’, a study published by the US National Bureau of Economic Research
https://scholar.harvard.edu/files/joshuagoodman/files/w24639.pdf

Heschong Mahone Group Study
http://h-m-g.com/projects/daylighting/summaries%20on%20daylighting.htm

‘Reduced cognitive function during a heat wave among residents of non-air-conditioned buildings: An observational study of young adults in the summer of 2016’ The full study:

http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002605

No.12: Solar Shading – how to integrate solar shading in sustainable buildings, REHVA

http://www.rehva.eu/publications-and-resources/eshop/eshop-detail.html?tt_products%5BbackPID%5D=1560&tt_products%5Bproduct%5D=40&tt_products%5Bcat%5D=3&cHash=9ee0aab2677ef586b60244bce3c1e5c5