In Indonesia, temperatures remain high throughout the year without any real winter season, making indoor conditions unbearable for residents. Most people don’t have air-conditioning, and those who do have low-quality units that do little to reduce the heat.
Finding a means to abate that oppressive heat was a reason Beta Paramita, an architecture professor at Universitas Pendidikan Indonesia, joined Clean Cooling Collaborative’s Million Cool Roofs Challenge. In competition with 10 other countries, including Bangladesh, Kenya, and Senegal, she collaborated with the University of Florida to launch a program—winner in the Social Justice category of the 2023 Innovation by Design Awards—that covers building roofs with a cooling white paint, originally made by another U.S. partner, Millennium Solutions.
The sun’s ultraviolet rays bounce off the paint’s tiny enamel particles, which can reflect up to 84% of sunlight. Buildings absorb less heat, reducing temperatures indoors considerably; at one industrial plant, indoor temperatures dropped by 20 degrees Fahrenheit. Most buildings in dense Jakarta had lower drops because less circulation means the heat that is retained stays trapped—but even there, humidity is alleviated significantly. “We were all surprised by the drop of the surface temperature,” Paramita says. “It’s quite a huge impact.”
The solution is also a more-sustainable alternative to air-conditioning. Indonesia is set to develop 21.5 billion square feet of residential area by 2030, with the potential for 22 million new air conditioners, which threaten to blow out the energy grid in the future.
Paramita’s model was chosen as the best among the entrants, winning prize money of $750,000. As of now, they’ve painted the roofs of about 70 buildings in 15 cities, including schools, an orphanage, and 36 affordable-housing complexes, impacting about 10,000 people.
The next challenge will be deploying it on a large scale. They’re now producing the paint in Indonesia, with a registered trademark, helping to lower the cost of imports from the U.S.—and the production and application has created 100 jobs, with the potential for more. Crucially, the tech is gaining recognition, as neighboring countries, including Malaysia and Singapore, have signaled interest to follow suit.