David Thorpe, The Fifth State writes in detail about the impact that active cooling methods are having on the planet and the benefits of using passive cooling methods instead.
The amount of energy used worldwide to cool buildings has doubled since the year 2000 and without efficiency gains, this could double again by 2040.
The Fifth State has identified a number of passive techniques for keeping cool which centre around not letting the heat enter the building in the first place; meaning that there is then no heat to be removed to cool the building down.
‘Some tactics for providing shading are: Covering pergolas with deciduous vegetation (allowing winter solar access) such as creepers or grapevines permits evaporation from the leaf surfaces to reduce the temperature… For east and west walls and windows in summer: vertical shading and/or deciduous trees and shrubs… For south-facing windows: horizontal shading… Shutters, louvres or blinds, closed in the day.’
The BBSA conducted a detailed study on a North London flat during a warm September to assess the effectiveness of shading.
By comparing three rooms; one with no shading, one with external shading and one with internal shading, the research was able to conclude that external shading can reduce internal temperatures by between 11 – 18C and is the most effective form of shading.
The bedroom reached a scorching 47.5C without any shading. External shading (Venetian or screen roller blinds) reduced this to a more acceptable 28C.
The BBSA agree with David Thorpe and the research conducted in our study of an overheating flat supports the theory discussed in his article ‘Ways to keep cool without costing the planet Part 1: Passive cooling.’
Read the full article here: https://www.thefifthestate.com.au/housing-2/ways-to-keep-cool-without-costing-the-planet-part-1-passive-cooling/
Read the overheating study: https://shadeit.wpengine.com/wp-content/uploads/2018/03/Overheating-in-September.pdf