THE ALBEDO EFFECT TO COOL URBAN CENTRES
Global warming on the rise
In France, temperatures over the last decade have only increased. If in 1920, the average temperature was 12.1°C (i.e. +0.3°C above seasonal norms), in 2020 the average was 14°C (i.e. +2.2°C above seasonal norms). This graph illustrates the evolution of the average temperature per year in France over a period of 120 years, from 1900 to 2020.
Source : Le Monde
Unfortunately, this rise in temperature is not a national problem. On a global scale, the situation is alarming. 2016, 2019 and 2020 are the three hottest years ever recorded, according to a press release dated 15 January 2022 from the World Meteorological Organisation (WMO).
In the face of this worrying data, the member states that signed the Paris Agreement have committed to limiting global warming to less than 2°C above pre-industrial levels. Reflecting on the characteristics of facade materials and exterior cladding is one way to improve urban heat control, both inside and outside.
The albedo effect: definition
In urban areas, where rising temperatures are felt the most, heat is partly linked to the cladding and materials used in buildings. It is therefore becoming urgent to change our building habits by adapting the choice of materials and redesigning public space.
One of the characteristics of the material to be taken into account is its capacity to reflect the sun’s rays without storing them. This is known as the albedo effect. The greater the albedo effect is, the lower the urban heat is, as itis automatically reflected back into the atmosphere.
The albedo therefore measures “the capacity of a surface to reflect incident solar energy”. This rate varies from 0 (all the incident energy is absorbed in the case of a totally black surface, for example) to 1 (all the incident energy is reflected).
Source: Lille Low Carbon Pact / Extract from the reference framework – version of 27/08/2021
The contribution of the textile membrane
Light colours contribute significantly to the albedo effect.
SMC2 contributes to the deployment of this albedo effect by covering its sports and leisure buildings with a textile membrane. The white stretched fabric will protect the infrastructure from bad weather and allow natural light to pass through while reflecting heat. Its albedo is close to 1, thus guaranteeing a reduction in the heating of the sites concerned. This provides ideal playing comfort for sportsmen and women, an environmentally friendly building and a general contribution to reducing global warming, especially in cities.
Textile roofing is particularly popular in the school sector. Our playgrounds, with their tensioned fabric cover, offer a pleasant refuge for schoolchildren to play and develop. They are protected from the weather and provide a welcome shade in schoolyards that are often too hot.
