When it comes to protecting the climate, everything matters. Emissions need to be reduced by over 90%, which means that little things can become big things if they’re ignored. Sectors that only occupy single figure percentages of total emissions suddently start to loom large as the carbon budget shrinks – cement, aviation, or air conditioning.
If current trends continue, there will be 5.6 billion AC units in the world by 2050, and their combined energy needs would be the same as China’s electricity use today. Air conditioning could derail the climate on its own, and of course global warming drives demand for AC.
As the world warms, hotter countries need to find ways to cool buildings naturally. There are lots of ways of doing that, some of them long established techniques, some of them new. Here’s one project that demonstrates some interesting solutions.
Universidade Agostinho Neto is a new build university campus in Luanda, Angola, named after the country’s first president. It was completed in 2011 by the global architecture firm Perkins & Will, built in a modernist style to complement similar buildings in the Angolan capital. The campus spreads out around a central courtyard with the library in the middle, which is partly built underground. All the classrooms and faculty buildings that surround the library use natural cooling and ventilation.
To do this, the campus is carefully oriented around the prevailing winds, so that air can blow through the buildings. Taller blocks are built behind lower ones so that they don’t end up in a wind shadow. One of the distinctive features is the canopies that stretch between the buildings and over the top of them. These provide shade and reduce solar gain, but they are also designed as airfoils. They reduce air pressure above the building, which naturally draws warm air out and upwards.
Angola’s national university is a good example of a thoroughly modern campus that doesn’t rely on modern technology to maintain comfortable temperatures. It uses geography, physics, and a good understanding of how light and air move through and around a building. It combines ancient techniques such as louvres and brise-soleils, with advanced science such as the computer modelling that optimised the airfoil roof.
These sorts of approaches can help to reduce the need for air conditioning in new buildings, not just in Africa, but anywhere with high summer or year round temperatures. And by resisting the quick fix of air conditioning, we can help to keep the whole planet cooler in the long term.