Now three teenagers from Malaysia have won an innovation competition with their affordable and sustainable air-conditioning system.
First rainwater is collected in a container. A sensor monitors the room temperature at home, activating a water pump if it exceeds 30 degrees.
This, in turn, feeds into a sprinkler system, which distributes the rainwater evenly across the roof. The water evaporates, cooling the rooms below.
Excess water, meanwhile, is recaptured and stored. Electricity for the system, which can be connected to an app, comes from a solar panel.
The project has shown the teens that they, too, can make a difference. Locally, and globally.