Freshly Baked Science
Cool As A Cucumber
3rd June 2018
When it comes to summertime it can get uncomfortably hot. The best way to keep cool is air conditioning (for us Brits, that’s the source of the much needed cold blast, as you walk into a foreign supermarket sunburnt and sweaty).
Due to its major popularity with people living in hot climates, summer can be a time when energy consumption goes through the roof. This isn’t just bad for our bank accounts, but the environment too!
So what else can we do (apart from turning down the sun’s thermostat)?
Scientific researchers have managed to develop a high-tech paint, which can cool when it’s exposed to sunlight. It’s essentially a paint-able layer of ice, which thickens when the sun comes out!
This new technology is based on ‘laser-cooling’, where specially designed materials can be cooled by up to 150°C by shining a laser at them. This works, because the molecules in the material will absorb photons (light particles) of a certain frequency, and re-emit higher frequency (higher energy) photons. This loss of energy reduces the temperature of the material.
The researchers had to find a way to swap the laser beam for a slightly bigger source of light (aka. the Sun). This proved difficult, as the sun has a much broader spectrum of light. Eventually, they produced a paint with two layers:
Outer layer– this filters out some of the suns rays, to reduce the spectrum
Inner layer– with the heat-light conversion property
The paint has undergone full lab testing, with a conclusion that it has the best effect under metal roofs, rather than concrete, and in houses with lower ceilings. With the use of the paint, the top floor of a house can be 10°C cooler than without the coating! This is so much more effective than the current method of painting houses in hot countries white, which prevents heat absorption throughout the day but can’t actively reduce the temperature.
As great as this concept is, once the pilot tests have been finished over the next couple of years, the paint will set its customers back £230 per square 100m. It is assumed that the earlier adopters will be larger commercial buildings, such as shopping centres and stadiums, before being used more widely.
These paints can potentially reduce energy consumption by over 60%, meaning a cheaper energy bill, and reduced carbon emissions (a win, win)! As well as this, the use of air con in hot cities can create ‘urban heat islands‘. This basically means the city becomes much hotter than the surrounding rural areas, due to human activity. Cutting back on AC use could really lower this effect.
Is the use limited to buildings though?
Just kidding, this high-tech paint has some exciting prospects for space. This sounds odd, as space is notoriously very cold, so why would it need anything making it colder!? Well, due to the atmosphere, there isn’t any air to carry the heat away, so all our technology we’ve planted up there can very easily overheat. In the future, this paint could potentially be used to counteract this problem!
Overall, this very cool (no pun intended) new coating could start to become the replacement for air con. This would drastically reduce our energy consumption as a planet, and would also save your parents some money in the long term. It could also have many other uses, with space technology just being the start!