New white paint could help cut building carbon emissions
With buildings being one of the leading carbon emitters, you might be interested to know how a new form of paint can contribute to lowering emissions and saving the planet.
In a report published in September 2019, the World Building Green Council highlighted that a significant chunk of the world’s carbon emissions comes from buildings. By simply regulating temperature and powering lighting systems, buildings emit 28 per cent of the world’s carbon emissions, through what the report termed ‘operational emissions.’
With this in mind, attempts are being made to find innovative ways to keep carbon emissions low. One way of doing so could be through using a new form of paint which could help cool buildings, cutting the reliance on air conditioning.
The inhabitants of Santorini know all too well that painted white surfaces reflect heat and sunlight effectively. This very phenomenon is now integral to helping scientists find more efficient ways to control heating and cooling, and it could all start with paint.
Paint could offset air conditioning needs
The findings of a study surrounding a new form of white paint were published in the journal Cell Reports Physical Science. Experiments were carried out with an acrylic paint containing high concentrations of calcium carbonate. The paint was found to reflect 95.5 per cent of the sun’s rays, while keeping the surface temperatures 1.7 degrees Celsius below ambient temperature at noon.
The study added that, by night-time, the paint was able to keep surface temperatures as much as 10 degrees below ambient temperature.
The higher amount of reflected sunlight means that less heat would be absorbed into a building during the day, and less heat radiated as the day wears on. This is all part of a process that scientists call ‘passive radiative cooling’, where highly reflective surfaces allow sunlight and heat to be bounced off into deep space.
This significant cooling observed in the experiment was deemed large enough to potentially offset the temperature requirements for air conditioning the average building, according to Professor Xiulin Ruan, one of the study’s authors. Such a cooling effect could mean buildings of the future may require far less air conditioning during the summer months.
Cheaper, greener ways to stay cool
While the study was keen to stress that the paint requires further testing before becoming commercially available, researchers felt optimistic about their findings. For consumers at large, this could be a significant moment in the fight against climate change.
As mentioned, buildings are one of the prime producers of carbon emissions worldwide. Air conditioning systems are often very expensive for anyone wishing to install them from scratch. Operating costs for these units are also a significant cost moving forward, and air conditioning in itself is highly energy-intensive. This costs the planet even greater amounts, in ways that can be hard to see with the naked eye.
In contrast, paints which allow radiative cooling are now demonstrably able to produce a remarkably strong temperature-regulating effect without having to burn the oil, gas or coal that an air conditioning system needs to function. In this case, a more old-school approach could be the key to cutting emissions in the future. Perhaps, in order to truly go green, a whitewash is just what we need?