Another sign of the shifting balance of economic power: the growth of “megacities.” The planet now has 28 cities with more than 10 million inhabitants, and 19 of them are in Asia and Africa. And while they’re all potent economic engines, they also face massive challenges: poverty, congestion, pollution, strains on natural resources, and more.
Amid the chaos, however, some remarkable innovations are emerging. In Cairo, the Zabaleen people — who have long made their living collecting and reusing the city’s refuse — have been given training and funds to organize microenterprises to convert trash into marketable products. In India, engineers have come up with the ChotuKool, a battery-powered, portable refrigerator that uses a thermoelectric chip instead of a compressor to cool food and minimize power consumption. And in Lagos, Nigeria, an architect named Kunlé Adeyemi has unveiled an audacious plan to build a network of homes atop flotation devices — both as a way to combat overcrowding and deal with the floods that occasionally surge through the low-lying, coastal city.
The efforts are small, but critical. The U.N. projects there will be 13 more megacities in the developing world by 2030.