Technology singularity:

This CityUHK coating, called the “smart skin” is based on the Tillandsia plant, which has two functions: it passively cools by reflecting more than 95 percent of incoming solar radiation and emitting infrared radiation to the outer space, resulting in a cooling effect of up to 9.5 degrees Celsius below ambient temperature and significantly reducing air conditioning requirements; as well as generating electricity through the triboelectric effect of rain falling on the surface of the coating (which can also be used to charge devices) - both of these functions make this coating an excellent choice for creating energy-efficient, sustainable cities through painting it on existing buildings.